JP3792202B2 - 3D image display method and 3D image display apparatus used therefor - Google Patents

Description

【００５９】
これらの条件を満たすエントランスが複数見つかった場合は、ベクトルＱの長さが最小のものを次候補空間として採用する。このような計算を前述の図３のフローチャートのステップS13 で全てのエントランスについて行なえば、ある時刻の視点位置と視点方向に対して角度θの視野範囲に存在するエントランスを発見することが可能である。
【００６０】
ところで、以上の例は、視点がある空間から他の空間へ移動する場合の画面の切り換えに際して、新たな空間を表示するためのデータを3Dデータベース51から待機メモリ59に予め読み出しておく予測読み出しを行なうことにより、視点の位置がある空間から他の空間へ移動したことが判明した時点からの3Dフレームバッファ55への必要なデータの書き込みに要する時間そのものを短縮するための手法である。
【００６１】
しかしそれでもなお、待機メモリ59のデータを3D描画部53に移して3Dフレームバッファ55に描画しても、モニタ56の画面上に実際に画像が表示されるまでにはある程度の時間が必要であり、その間は画面にはなにも表示されないか、またはそれまでの表示状態がそのまま静止画像で維持されるため、利用者にとっては手持ち無沙汰な状態を強いられることになる。このような事情から、本発明の以下の各実施の形態においては、モニタ56の画面上に完全な3D画像が表示されるまでの間の表示状態を工夫して利用者の手持ち無沙汰な状態を解消することを図っている。
【００６２】
〔第１の実施の形態〕
本発明の第１の実施の形態においては、初期3D画像を予め二次元化した2D画像を用意するが、この2D画像（初期3D画像）にはたとえば後述する「フォグ（霧）効果」等のフィルタ処理を利用して色を抑える処理を行なう。そして、最初の１回目においてのみフォグ効果を利用した画像を表示する。即ち、最初の一回目の表示の際にのみ2D画像（初期3D画像を二次元化した画像）が色を抑えた状態で表示され、その後は順次3D画像が2D画像上に上書き表示されてゆく。
【００６３】
このような手法では、3D画像は本来の色で表示されるため、画面内で色が抑えられている部分は3D描画が未処理であり、濃い色で表示されている部分は3D描画が既に終了したオブジェクトであるということが利用者には明確に識別可能になる。このことにより、利用者は3D描画がどの程度進行しているかを即座に認識することが可能になる。
【００６４】
ところで、フォグ効果の実際は一例としては以下のような計算方法によることが可能である。たとえば3Dフレームバッファ55（図６参照）内の一つの画素が三原色（赤(R),緑(G),青(B))で表現されているとする。この場合、たとえば”０”以上”１”以下の範囲の値をとる定数ｋを使って、
ｒ＝Ｒ＊ｋ, ｇ＝Ｇ＊ｋ, ｂ＝Ｂ＊ｋ
なる画素値ｒ, ｇ, ｂを計算により求め、これを一つの画素（ｒ, ｇ, ｂ）とすると、簡単なフォグ効果が得られる。
【００６５】
なお、上述のようなフォグ効果のみならず、簡単な計算によって元の画素値より値を下げた画素値が容易に得られる操作であれば、他の処理手法を利用することも勿論可能であることは言うまでもない。
【００６６】
以下、第１の実施の形態の構成例を示す図６のブロック図及び表示状態を示す図７の模式図を参照して具体的に説明する。
【００６７】
図６において、参照符号51は三次元データベース（3Dデータベース) であり、三次元空間を構成する立体、即ちオブジェクトのデータが格納されていることは前述の本発明が適用される三次元画像表示装置と同様であるが、この第１の実施の形態では、各エントランスから各空間を見た初期3D画像を二次元化した2D画像のデータも格納されている。
【００６８】
参照符号52は視点PVが現在位置している空間に関するデータを3Dデータベース51から読み出すためのリーダである。このリーダ52により3Dデータベース51から読み出されたデータは3D描画部53に与えられる。なお、空間の切り換えが行なわれる場合には、3Dデータベース51から初期3D画像に対応する2D画像のデータがリーダ52によって読み出され、2D描画部62へ転送される。
【００６９】
3D描画部53では、リーダ52が読み出したデータに基づいて、また視点情報設定部54から与えられる視点情報、即ちいずれの位置から見ているかを示す情報に従って、各オブジェクトについて幾何計算, 色計算等を行なってその結果を3Dフレームバッファ55に書き込む。3Dフレームバッファ55に書き込まれた画像はモニタ56へ送られて表示される。
【００７０】
2D描画部62は、空間の切り換えが行なわれた場合に与えられる初期3D画像に対応する2D画像のデータを3Dフレームバッファ55に描画する。この2D描画部62にはフィルタ強度設定手段として機能するフォグパラメータ設定部71が接続されている。フォグパラメータ設定部71には”０”以上”１”以下の範囲の値の任意のフォグパラメータが設定可能である。
【００７１】
このような本発明の第１の実施の形態の動作は以下の如くである。いま、視点がある空間内に位置しているとすると、従来例と同様にして、リーダ52が3Dデータベース51から読み出したデータを視点情報設定部54から与えられる位置情報に従って3D描画部53が3Dフレームバッファ55に描画することにより、モニタ56の画面にはその空間内の画像が表示されている。
【００７２】
このような状態から空間の切り換えが行なわれると、視点情報設定部54から与えられる視点情報に従って3Dデータベース51から初期3D画像を表示するためのデータがリーダ52によって読み出される。この初期3D画像を表示するためのデータには2D画像のデータが含まれており、3Dフレームバッファ55経由で2D描画部62に転送される。
【００７３】
ところで前述の如く、フォグパラメータ設定部71には予めフォグ効果のパラメータ、即ちフォグパラメータｋ（０≦ｋ≦１）が設定されている。2D描画部62はこのフォグパラメータ設定部71に設定されているフォグパラメータｋを2D画像の各画素値（Ｒ, Ｇ, Ｂ）に乗じて新しい画素値（ｒ, ｇ, ｂ）を求め、その結果を3Dフレームバッファ55に書き込む。3Dフレームバッファ55に書き込まれた画像はモニタ56の画面に表示される。この表示状態を図７(a) に示す。ここでは、フォグパラメータ設定部71により設定されたフォグパラメータｋに応じて色が抑えられた2D画像が表示される。
【００７４】
次に、リーダ52は3Dデータベース51の先頭からまず一つのオブジェクトのデータを読み出し、3D描画部53へ転送する。3D描画部53は空間が切り換えられた場合の初期状態として予め設定されている視点位置情報と3Dデータベース51から読み出されたオブジェクトデータとに基づいて三次元の描画計算を行なって3Dフレームバッファ55に描画を行なう。このようにして一つのオブジェクトの3Dフレームバッファ55への描画が完了すると、図７(b) に示されているように、そのオブジェクトの画像のみがモニタ56の画面上に明瞭に表示される。
【００７５】
以下、同様にリーダ52は3Dデータベース51から順次他のオブジェクトのデータの読み出し及び3Dフレームバッファ55への描画を行ない、やがて一つの空間の全データの読み出し及び3Dフレームバッファ55への描画が完了する。この状態では図７(c) に示されているように、明瞭な初期3D画像がモニタ56の画面に表示される。
【００７６】
このように本発明の第１の実施の形態では、視点位置が別の空間に移動して空間の切り換えが行なわれる際には、初期3D画像が表示されるまでの間にそれを二次元化した画像を更にフォグパラメータにより色を抑えた画像が表示され、その後に実際に表示されるべき初期3D画像が順次重畳して表示されてゆく。従って、利用者にとってはどの程度まで3D画像の描画進んでいるかが容易に認識可能になる。
【００７７】
〔第２の実施の形態〕
次に第２の実施の形態について説明するが、この第２の実施の形態では、データベースから読み出されたデータに対して上述の第１の実施の形態と同様の色抑えのためのフィルタ処理（たとえばフォグ効果）を施し、再度3Dフレームバッファ55に戻して画面表示する。その際、ある決められた時間間隔、または3D描画部53でのオブジェクト描画の進行に伴って、上述のような処理を反復する。また同時に、色の抑え処理の回数進行に伴ってフォグパラメータを”０”または”０”に近い値から段階的に”１”に近付けてゆき、3D描画が完了する時点では色抑え処理をしない状態、即ちフォグパラメータを”１”にする。換言すれば、フォグパラメータｋを、最初は”０”にしておき、処理回数が進むにつれて段階的に漸増させ、最後は”１”になるように制御する。
【００７８】
この第２の実施の形態によれば、最初は3D描画結果の表示は色が薄く、その後に3D描画が進むに伴って色が濃くなってゆくという画面効果が得られる。これにより、利用者は3D描画がどの程度進行しているかを直観的に把握することができる。
【００７９】
以下、第２の実施の形態の構成例を示す図８のブロック図及び表示状態を示す図９の模式図を参照して具体的に説明する。
【００８０】
図８において、参照符号51は三次元データベース（3Dデータベース) であり、三次元空間を構成する立体、即ちオブジェクトのデータが格納されていることは前述の本発明が適用される三次元画像表示装置と同様である。
【００８１】
参照符号52は視点が現在位置している空間に関するデータを3Dデータベース51から読み出すためのリーダである。このリーダ52により3Dデータベース51から読み出されたデータは3D描画部53に与えられる。
【００８２】
3D描画部53では、リーダ52が読み出したデータに基づいて、また視点情報設定部54から与えられる視点情報、即ちいずれの位置から見ているかを示す情報に従って、各オブジェクトについて幾何計算, 色計算等を行なってその結果を3Dフレームバッファ55に書き込む。3Dフレームバッファ55に書き込まれた画像は一旦2D描画部62に転送される。
【００８３】
2D描画部62にはフィルタ強度変更手段として機能するフォグパラメータ更新部72が接続されている。2D描画部62は、3Dフレームバッファ55に描画された画像に対してフォグパラメータ更新部72にその時点で設定されているフォグパラメータに従って色抑え処理を施し、その結果を再度3Dフレームバッファ55に描画する。フォグパラメータ更新部72は”０”〜”１”の範囲で段階的にフォグパラメータｋを更新する。
【００８４】
このような本発明の第２の実施の形態の動作は以下の如くである。いま、視点がある空間内に位置しているとすると、従来例と同様にして、リーダ52が3Dデータベース51から読み出したデータを視点情報設定部54から与えられる位置情報に従って3D描画部53が3Dフレームバッファ55に描画することにより、モニタ56の画面にはその空間内の画像が表示されている。
【００８５】
このような状態から空間の切り換えが行なわれると、視点情報設定部54から与えられる視点情報に従って3Dデータベース51から初期3D画像を表示するためのデータがリーダ52によって読み出され、視点情報設定部54により3Dフレームバッファ55に描画されると共に、その結果が2D描画部62に転送される。具体的には、リーダ52は3Dデータベース51の先頭からまず一つのオブジェクトのデータを読み出し、3D描画部53へ転送する。3D描画部53は空間が切り換えられた場合の初期状態として予め設定されている視点位置情報と3Dデータベース51から読み出されたオブジェクトデータとに基づいて三次元の描画計算を行なって3Dフレームバッファ55に描画を行なう。
【００８６】
ところで、3Dフレームバッファ55に描画された3D画像は所定の時間間隔または3Dフレームバッファ55にオブジェクトが一つ描画される都度、2D描画部62へ転送される。ここでは一例として、3Dフレームバッファ55への描画処理済みのオブジェクトの数に基づいて3Dフレームバッファ55上のデータが2D描画部62へ転送されるものとする。
【００８７】
2D描画部62にはフォグパラメータ更新部72が接続されているが、このフォグパラメータ更新部72はフォグパラメータｋを以下のように逐次変更する。即ち、フォグパラメータ更新部72に予め初期設定されているフォグパラメータｋをk0とする。更に、更新定数をｄ（ここでは、ｄ＝（１−k0）／Ｎに設定しておく）として、3D描画部53がオブジェクトを一つ描画処理してその結果が2D描画部62に転送される都度、以下のようにフォグパラメータｋを更新する。
【００８８】
ｋ ← ｋ＋ｄ
【００８９】
このようにフォグパラメータの更新を行なうことにより、最初はｋ＝k0から始まり、全てのオブジェクトが処理された時点ではｋ＝１となる。このフォグパラメータｋを使ってフォグ効果を発揮させる。具体的には、3D描画部53がオブジェクトを一つ描画処理すると、2D描画部62はその時点を更新タイミングとして3Dフレームバッファ55の内容を一旦読み出し、その画像の画素値（Ｒ, Ｇ, Ｂ）に対してフォグパラメータ更新部72により更新されているフォグパラメータｋを乗じて画素値（ｒ, ｇ, ｂ）に変換した後に3Dフレームバッファ55に書き戻す。
【００９０】
このようにしてまず最初の一つのオブジェクトの3Dフレームバッファ55への描画が完了すると、図９(a) に示されているように、その最初の一つのオブジェクトの画像のみが色を抑えたフォグ効果付きでモニタ56の画面上に表示される。
【００９１】
以下、同様にリーダ52は3Dデータベース51から順次他のオブジェクトのデータの読み出し及び3Dフレームバッファ55への描画を行ない、次のもう一つのオブジェクトの3Dフレームバッファ55への描画が完了すると、図９(b) に示されているように、最初の一つのオブジェクトと次の一つのオブジェクトの画像が色を抑えたフォグ効果付きで、しかし最初の一つのオブジェクトのみが表示されていた状態よりは濃い色でモニタ56の画面上に表示される。
【００９２】
やがて一つの空間の全データの読み出し及び3Dフレームバッファ55への描画が完了する。この状態では図９(c) に示されているように、明瞭な初期3D画像がモニタ56の画面に表示される。
【００９３】
このように本発明の第２の実施の形態では、視点位置が別の空間に移動して空間の切り換えが行なわれる際には、初期3D画像が完全な状態に表示されるまでの間に、個々のオブジェクトが表示される都度、フォグパラメータにより色を抑えた状態から完全な状態までに段階的に表示される。従って、利用者には3D描画がどの程度進行しているかが認識可能になる。
【００９４】
〔参考例〕
本参考例では、3Dオブジェクトを格納したデータベースを操作することにより、オブジェクトを最適な順序で読み出すようにする。
【００９５】
一般に、三次元画像を描画する際には視点に近い物体から遠い物体の順に見えるように表示すれば自然な感じが得られる。従って、本参考例では原則として、視点と各オブジェクトとの間の距離を予め計算し、各オブジェクトを視点から近い順に3D描画する。但し、何らかの事情、たとえば特殊な画面効果を得るために各オブジェクトを視点から遠い順に3D描画するようにしてもよいことは言うまでもない。
【００９６】
具体的には、視点位置情報に従ってデータベース内の各オブジェクトと視点位置との間の距離を計算し、それを小さい順（あるいは逆）にソーティングし、その結果に基づいてデータベース内のオブジェクトデータの配列を変更するか、順序を示すフラグを立てておく。3Dデータベースから3Dデータが読み出される場合には、データベースの先頭から、あるいは順番フラグの小さいものから順に読み出され、3D描画が行なわれる。
【００９７】
以下、本参考例の構成例を示す図10のブロック図，従来の表示状態を示す図11の模式図及び本参考例の表示状態を示す図12の模式図を参照して具体的に説明する。
【００９８】
図10において、参照符号51は三次元データベース（3Dデータベース) であり、三次元空間を構成する立体、即ちオブジェクトのデータが格納されていることは前述の本発明が適用される三次元画像表示装置と同様である。なお、3Dデータベース51には後述するソータ73接続されている。
【００９９】
参照符号52は視点PVが現在位置している空間に関するデータを3Dデータベース51から読み出すためのリーダである。このリーダ52により3Dデータベース51から読み出されたデータは3D描画部53に与えられる。
【０１００】
3D描画部53では、リーダ52が読み出したデータに基づいて、また視点情報設定部54から与えられる視点情報、即ちいずれの位置から見ているかを示す情報に従って、各オブジェクトについて幾何計算, 色計算等を行なってその結果を3Dフレームバッファ55に書き込む。3Dフレームバッファ55に書き込まれた画像はモニタ56へ送られて表示される。
【０１０１】
ここで、分類手段として機能するソータ73について説明する。視点位置情報を（ex, ey, ez）のように三次元空間内の座標値で表現すると、ソータ73は視点情報設定部54から与えられる視点位置情報と3Dデータベース51内の各オブジェクトデータとを比較し、視点位置からの距離が短いもの順に番号を付ける。
【０１０２】
具体的には以下の如くである。3Dデータベース51内の個々のオブジェクトをOj（ｊ＝１〜Ｎ）とする。オブジェクトOjを構成する点座標を（xi, yi, zi）（但し、ｉは点の番号）とし、オブジェクトOjを囲むバウンダリボックス、即ちオブジェクトOjを含む仮想的な直方体の位置を計算する。バウンダリボックスは三次元空間内の２点ａ, ｂで表現することが可能であり、この座標を（xa, ya, za）, （xb, yb, zb）とすると、ａ, ｂは以下のようにして求められる。
【０１０３】
xa ＝ Min(xi), ya ＝ Min(yi), za ＝ Min(zi)
xb ＝ Max(xi), yb ＝ Max(yi), zb ＝ Max(zi)
【０１０４】
ここで Min演算, Max演算はオブジェクトOj内の点座標全てにわたる最小値, 最大値を求める計算である。
【０１０５】
バウンダリボックスの重心（xgj, ygj, zgj)については、ａ点, ｂ点の中点を求めればよい。従って、以下のようにして視点位置から各オブジェクトOjの重心までの距離Djが求められる。

【０１０６】
このDjを全てのオブジェクトについて計算し、その結果から小さい順に3Dデータベース51内のオブジェクトデータの配置を並べ換える。並べ換えはたとえばクィックソートのような公知技術を使えば容易に可能である。この処理を行なった後に、リーダ52が3Dデータベース51の先頭からオブジェクトを読み出し、3D描画を行なえば視点から近い位置にあるオブジェクトから順に画面に表示可能になる。
【０１０７】
このような本参考例の動作は以下の如くである。いま、視点がある空間内に位置しているとすると、従来例と同様にして、リーダ52が3Dデータベース51から読み出したデータを視点情報設定部54から与えられる位置情報に従って3D描画部53が3Dフレームバッファ55に描画することにより、モニタ56の画面にはその空間内の画像が表示されているとする。
【０１０８】
このような状態から空間の切り換えが行なわれると、視点情報設定部54から与えられる視点情報に従って、ソータ73は上述のようにして3Dデータベース51内のオブジェクトデータを視点位置から近い順に並べ換える。この処理を行なった後に、3Dデータベース51から初期3D画像を表示するためのデータがリーダ52によって読み出され、3D描画部53により3Dフレームバッファ55に描画され、モニタ56の画面に表示される。
【０１０９】
たとえば、従来であれば、図11(a), (b)及び(c) に示されているように、空間内のいずれのオブジェクトからモニタ56に表示されるかは不明であったが、本参考例によれば、図12(a), (b)及び(c) に示されているように、視点位置に近いオブジェクトから順にモニタ56の画面上に表示される。
【０１１０】
なお、ある空間へ通じているエントランスが一つのみである場合には、その空間の初期3D画像の視点の位置は判明しているので、各オブジェクトのデータをソータ73により予め視点位置 (初期3D画像の視点位置) から近い順に並べ換えておけばよい。但し、複数のエントランスが通じている空間に関しては、その空間を表示する必要が生じる都度、ソータ73による並べ換えを行なうか、または各エントランスそれぞれに対応して予め並べ換えを行なっておくことも勿論可能である。
【０１１１】
このように本参考例では、視点位置が別の空間に移動して空間の切り換えが行なわれる際には、初期3D画像が視点位置に近い側から除々に表示されるため、利用者には3D描画がどの程度進行しているかが認識可能になると同時に、画面の近景から段階的に表示されるため、利用者に手持ち無沙汰な状態を強いる可能性は減少する。
【０１１２】
〔第３の実施の形態〕
次に第３の実施の形態について説明する。この第３の実施の形態では、3Dオブジェクトの粗い形状データから順次細かい形状データを読み出して表示してゆくようにする。このため、各オブジェクトについて粗い形状から細かい形状までのデータを多段階に予め作成してデータベースに登録しておく必要がある。しかし、利用者は3D世界のおおまかな配置や形状を予め知ることができ、また粗い形状から最終的な形状を想像する楽しみも与えられる。
【０１１３】
以下、第３の実施の形態の構成例を示す図13のブロック図, 及び表示状態を示す図15の模式図を参照して具体的に説明する。
【０１１４】
図13において、参照符号51は三次元データベース（3Dデータベース) であり、三次元空間を構成する立体、即ちオブジェクトのデータが格納されていることは前述の本発明が適用される三次元画像表示装置と同様である。なお、3Dデータベース51には、詳細は後述するが、3Dオブジェクトについて粗い形状から細かい形状までのデータを多段階に予め作成するための間引き手段として機能するLOD(Level-Of-Detail)作成部74が接続されている。この LOD作成部74は、3D描画を開始する前に予め3Dデータベース51内の各オブジェクトについて粗い立体データから細かい立体データまで多段階のオブジェクトデータを自動的に作成して3Dデータベース51に本来のデータと共に追加登録する。
【０１１５】
参照符号52は視点PVが現在位置している空間に関するデータを3Dデータベース51から読み出すためのリーダである。このリーダ52により3Dデータベース51から読み出されたデータは3D描画部53に与えられる。
【０１１６】
3D描画部53では、リーダ52が読み出したデータに基づいて、また視点情報設定部54から与えられる視点情報、即ちいずれの位置から見ているかを示す情報に従って、各オブジェクトについて幾何計算, 色計算等を行なってその結果を3Dフレームバッファ55に書き込む。3Dフレームバッファ55に書き込まれた画像はモニタ56へ送られて表示される。
【０１１７】
このような本発明の第３の実施の形態の動作について、 LOD作成部74によるテーブルの生成方法を示す図14の模式図及び表示状態を示す図15の模式図を参照して具体的に説明する。
【０１１８】
3D描画を開始する前にまず、 LOD作成部74が予め3Dデータベース51内の各オブジェクトについて粗い立体データから細かい立体データまで多段階のオブジェクトデータを自動的に作成して3Dデータベース51に本来のデータと共に追加登録しておく。
【０１１９】
LOD作成部74による処理は以下の如くである。3Dデータベース51内の一つのオブジェクトを構成するデータは図14の模式図に示されているようなような形式になっているとする。ここではオブジェクトを構成する面（ポリゴン）データが登録されたポリゴンテーブル（L-TABLE), 面データを構成する辺データが登録された辺テーブル（E-TABLE), 辺データを構成する点データが登録された点テーブル（P-TABLE)という階層構造をとる。
【０１２０】
いま、オブジェクトがポリゴン１, ポリゴン２・・・ポリゴンＰで構成されているとする。 LOD作成部74はL-TABLE から機械的にたとえば偶数番目のポリゴンを間引いてポリゴン１, ポリゴン３・・・という系列を別のポリゴンテーブル（L-TABLE ２）に書き込む。次に、 LOD作成部74はL-TABLE ２に書き込まれた各ポリゴンデータについて、それに対応した辺データを検索する。たとえばポリゴン１を構成する辺をｅ１, ｅ２, ｅ３・・・とすると、上述同様に偶数番目の辺を間引いてｅ１, ｅ３・・・という新しい系列を作り、ポリゴン１に対応した辺データ領域に書き込む。従って、L-TABLE ２内のポリゴン１の項は辺ｅ１, ｅ３・・・となる。
【０１２１】
以上の操作が完了した後、L-TABLE ２内に出現する辺データのみを新たな辺テーブルE-TABLE ２に登録する。その後、更にE-TABLE ２内に出現する点データのみを新たな点テーブルP-TABLE ２に登録する。このような手順で LOD作成部74がL-TABLE ２, E-TABLE ２及びP-TABLE ２を作成すると、この三つのテーブルで表現される新たなオブジェクトは本来のオブジェクトを約半分の面で表現した粗い立体モデルとなる。
【０１２２】
粗さを多段階としてモデルを自動作成するには、データの飛び越し量を適宜に設定することにより上述同様の処理を反復すれば、たとえばオリジナルモデルを含めて全部で（ｍ＋１）段階の粗さのモデル作成が必要な場合には、最初にデータの飛び越し量をｍに設定し、以下ｍ−１, ｍ−２, ・・・, １の順に設定して上述同様の処理を反復すればよい。
【０１２３】
以上のような処理を行なうことにより、一つのオブジェクトの段階的な複数の粗いモデルが新規に作成されると、 LOD作成部74はそれらのデータを3Dデータベース51の先頭に挿入して登録する。このような処理を行なうことにより、リーダ52は各オブジェクトのデータを読み出す際には、最も粗いモデルのデータを各オブジェクトに関してまず読み出し、図15(a) に示されているような各オブジェクトを粗い画像として表示する。次には、リーダ52は二番目に粗いデータを各モデルに関して読み出し、図15(b) に示されているような各オブジェクトをやや精細な画像として表示する。以下、同様にして段階的に粗いモデルのデータから順に読み出してモニタ56に表示してゆく。3Dデータベース51の後半には各オブジェクトのオリジナルのデータが格納されているため、最後の段階には、図15(c) に示されているように、モニタ上の粗いモデルはオリジナルのモデルに上書きされる。
【０１２４】
このように本発明の第３の実施の形態では、視点位置が別の空間に移動して空間の切り換えが行なわれる際には、初期3D画像を構成する各オブジェクトが非常に粗い画像としてまず表示され、順次的に精細な画像に上書きされて最後に本来の画像が表示されるため、利用者に手持ち無沙汰な状態を強いる可能性は減少する。
【０１２５】
〔第４の実施の形態〕
ところで、上述の第３の実施の形態では、ただでさえ大量のデータ容量が必要な3Dデータを格納する3Dデータベース51により以上の容量が要求されることになる。従って、3Dデータベース51の容量に余裕が無い場合には第３の実施の形態とほぼ同様の効果が得られる以下のような第４の実施の形態が好ましい。
【０１２６】
第４の実施の形態では、データベースからオブジェクトデータを読み出した後に粗い形状データを計算によって求め、それを順次表示する手法を採る。従って、予め粗い形状データを作成してデータベース内に格納しておく必要はない。
【０１２７】
以下、第４の実施の形態の構成例を示す図16のブロック図を参照して具体的に説明する。図16のブロック図に示されているように、この第４の実施の形態では、 LOD作成部74が3Dデータベース51に接続しているのではなく、リーダ52と3D描画部53との間に位置している。他の構成は図13に示されている第３の実施の形態と同様である。
【０１２８】
このような本発明の第４の実施の形態の動作は以下の如くである。ここでは一例として、全部で（ｍ＋１）段階の粗さのモデルを表示する場合について説明する。
【０１２９】
最初に LOD作成部74には粗さのパラメータとしてｍが設定される。リーダ52が3Dデータベース51から読み出した一つのオブジェクトのオリジナルデータが LOD作成部74に入力されると、 LOD作成部74は上述の第３の実施の形態の場合と同様の処理を行なって新たな粗いオブジェクトテーブル（L-TABLE ２, E-TABLE ２及びP-TABLE ２）を自動作成し、これらのテーブルに記述されたデータを一つのオブジェクトのデータとして3D描画部53へ転送する。3D描画部53はその粗さｍのモデルを3Dフレームバッファ55に描画する。リーダ52が3Dデータベース51から最後のオブジェクトを検出すると、次には粗さのパラメータをｍ−１に設定して再度、上述同様の処理を行なう。これにより今回は粗さ（ｍ─１）の立体モデルが LOD作成部74で自動作成され、3Dフレームバッファ55に3D描画されてモニタ56に表示される。
【０１３０】
以上の処理を反復することにより、最後に粗さ０のモデル作成を行なえば本来の画像がモニタ56の画面に表示されることになる。なお、この第４の実施の形態の表示状態は前述の第３の実施の形態の表示状態と同様である。
【０１３１】
このように本発明の第４の実施の形態では、第３の実施の形態同様に、視点位置が別の空間に移動して空間の切り換えが行なわれる際には、初期3D画像を構成する各オブジェクトが非常に粗い画像としてまず表示され、順次的に精細な画像に上書きされて最後に本来の画像が表示されるため、利用者に手持ち無沙汰な状態を強いる可能性は減少する。
【０１３２】
なお、前述の第３の実施の形態とこの第４の実施の形態との相違は、粗い画像のデータを予めデータベースに格納しておくか、実際の表示の際にその都度作成するかであるため、データベースの容量, 画像処理速度の程度等に応じていずれかを利用することが望ましい。
【０１３３】
【発明の効果】
以上に詳述した如く本発明によれば、利用者は三次元画像の描画が完了するまでの間、描画される画像に関する何らかの情報を予め用意した画面から得られる。特にその画面が現在描画計算している画像の最終結果を二次元化した画像であれば、次の画面を予め知ることが可能になる。
【０１３４】
更に、フォグ効果が順次薄れてゆくなどの画面効果が得られるフィルタ処理を利用した場合には、3D描画がどの程度進行したかを利用者が直観的に把握可能になる。またある空間の情景から別の空間の情景が除々に現れるため、利用者の心理的負担が軽減される。
【０１３５】
更にまた、次の3D画面がどのような配置でどのような物が見えるか、などといった情報が優先的に見られる。
【図面の簡単な説明】
【図１】本発明が適用される三次元画像表示装置の構成例を示すブロック図である。
【図２】図１の装置の予測読み出しの手順を示すフローチャートである。
【図３】本発明が適用される三次元画像表示装置が対象とする空間の例を示す模式図である。
【図４】エントランスの情報が登録されたテーブルの構成例を示す模式図である。
【図５】視線ベクトルとエントランス位置との関係を示す模式図である。
【図６】本発明の第１の実施の形態の構成例を示すブロック図である。
【図７】第１の実施の形態の画面表示の模式図である。
【図８】本発明の第２の実施の形態の構成例を示すブロック図である。
【図９】第２の実施の形態の画面表示の模式図である。
【図１０】 参考例の構成例を示すブロック図である。
【図１１】従来の画面表示の模式図である。
【図１２】 参考例の画面表示の模式図である。
【図１３】 本発明の第３の実施の形態の構成例を示すブロック図である。
【図１４】 LOD作成部によるテーブルの生成方法を示す模式図である。
【図１５】 第３の実施の形態及び第４の実施の形態の画面表示の模式図である。
【図１６】 本発明の第４の実施の形態の構成例を示すブロック図である。
【図１７】本発明が前提とする三次元空間の模式図である。
【図１８】従来のシステム構成例を示すブロック図である。
【符号の説明】
51 3Dデータベース
52 リーダ
53 3D描画部
54 視点情報設定部
55 3Dフレームバッファ
56 モニタ
57 入力デバイス
58 エントランス判定部
59 待機メモリ
62 2D描画部
63 2Dフレームバッファ
64 スイッチャ
71 フォグパラメータ設定部
72 フォグパラメータ更新部
73 ソータ
74 LOD作成部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a three-dimensional image display method and a three-dimensional image display apparatus, and more particularly to so-called computer graphics, and particularly to computer graphics for a three-dimensional space.
[0002]
[Prior art]
Computer graphics has recently been used in various fields, and in particular, with the development of so-called multimedia, attempts have been made to use it for communication with a remote place through a communication path. For example, communication such as storing the 3D model data on a server installed at a certain point and displaying the model data by loading it on a remote client terminal via the Internet, for example. Is possible.
[0003]
By the way, the system on which the present invention is premised is, first, a plurality of three-dimensional spaces to be drawn are prepared, and the viewpoint can be freely moved in one of these spaces. It has the feature of enabling “walk-through”.
[0004]
For example, as shown in the schematic diagram of FIG. 17, one indoor space (first space SP1) is configured by a set of several solid models OB, and another indoor space adjacent to this room. (Second space SP2) is composed of a set of several other solid models OB, and the spaces SP1 and SP2 are connected to each other via an entrance E as a connection point.
[0005]
For example, when the viewpoint PV moves through the entrance E from the first space SP1 to the second space SP2 by “walk-through”, the data of the second space SP2 of the movement destination is read from the database and displayed on the screen. Need arises. However, if there is a large amount of data of the solid model of the second space SP2 to be read and the communication capacity between the database and the display terminal is small, the screen of the room accompanying the room movement from the first space SP1 to the second space SP2 will be displayed. There is a long waiting time for switching. In other words, the waiting time from when the first space SP1 is displayed until the second space SP2 is displayed becomes longer.
[0006]
The block diagram of FIG. 18 shows a conventional system configuration example for the above-described three-dimensional space display. Hereinafter, a more specific description will be given with reference to FIG.
[0007]
In FIG. 18, reference numeral 51 is a three-dimensional database (hereinafter referred to as a 3D database), which stores data of a solid (hereinafter referred to as an object) constituting a three-dimensional space. However, as shown in the schematic diagram of FIG. 17, the three-dimensional space is divided into a plurality of spaces (in the example of FIG. 17, the space is divided into two spaces, the first space SP1 and the second space SP2). The data of the objects in the spaces SP1 and SP2 are managed as one data group.
[0008]
Reference numeral 52 is a reader for reading out data related to the space where the current viewpoint is located from the 3D database 51. Data read from the 3D database 51 by the reader 52 is provided to the 3D drawing unit 53.
[0009]
In the 3D drawing unit 53, based on the data read by the reader 52 and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating which direction from which position is viewed, geometric calculation, color The calculation is performed and the result is written in the 3D frame buffer 55.
[0010]
By repeating the operation of drawing each individual object, a 3D image of each object is sequentially drawn on the 3D frame buffer 55, and one 3D screen is eventually completed and displayed on the monitor 56. .
[0011]
A case will be considered below in which such a conventional system is used to move between a plurality of three-dimensional spaces (hereinafter referred to as 3D spaces) as shown in FIG. It is assumed that several 3D models, that is, objects OB are arranged in each 3D space (first space SP1 and second space SP2 in the example of FIG. 17). For example, it is assumed that the current viewpoint PV is located in the first space SP1 and is walking through in a certain direction along the path P.
[0012]
When the viewpoint PV moves from the first space SP1 to the other second space SP2, the space is switched and the three-dimensional image displayed on the monitor 56 is also switched. It is necessary to newly read out information of the second space SP2 to be performed from the 3D database 51 and draw an image in the 3D frame buffer 55. In general, the amount of data of the three-dimensional model set is very large, and it takes a considerable time to read the data into the 3D frame buffer 55. However, in the real world, the viewpoint PV can be smoothly moved from one room to another room, that is, the first space SP1 to the second space SP2, whereas the conventional system as described above is used. In the three-dimensional image display method using, the viewpoint cannot be moved smoothly at the boundary between the rooms (for example, a door), and a waiting time occurs.
[0013]
The system premised on the present invention is secondly characterized in that a plurality of objects constituting one three-dimensional space exist.
[0014]
For example, assuming that the number of objects constituting one three-dimensional space is N, in the conventional method, the data of these N objects are stored in the 3D database 51, and the reader 52 stores the data for each object. The 3D rendering unit 53 repeats the operation of performing geometric calculation and color calculation for each object according to the viewpoint information given from the viewpoint information setting unit 54, and writing the result to the 3D frame buffer 55. A screen is created.
[0015]
Therefore, conventionally, as the object data is sequentially written to the 3D frame buffer 55, the appearance of each object is sequentially displayed on the monitor 56, or all the object data is written to the 3D frame buffer 55. After that, all the objects were displayed on the monitor 56 at the same time.
[0016]
In the former case, the user who is watching the monitor 56 is not given information such as how long the user waits until one screen is completed or how much drawing is currently progressing. For this reason, it is unclear how long to wait, and it will be forced to have a hand-held state.
[0017]
In the latter case, the screen display on the monitor 56 disappears until all the drawing is completed in the 3D frame buffer 55, or the display state up to that point is maintained as a still image.
[0018]
[Patent Document 1]
JP-A-1-250288
[0019]
[Problems to be solved by the invention]
In general, the more complicated a 3D stereo model, the larger the amount of data. Therefore, if the communication capacity between the database system (server) storing the stereo model data and the display terminal (client) is small, communication is required. Due to the increase in time, it takes a long time to move from the drawing space to another space. Accordingly, how to prevent the user from feeling the waiting time for the movement is a problem to be solved.
[0020]
In the present invention, it is possible to perform “walk-through” over a plurality of three-dimensional spaces, and it is assumed that data of a three-dimensional model in a space is loaded from a database when a viewpoint first enters the space. . Therefore, how to make the user feel the waiting time at the time of switching such a display, how quickly to convey to the user what kind of screen is about to be displayed next, etc. Is a problem to be solved.
[0021]
The object of the present invention is to improve the display state during the waiting time necessary to display a space where the viewpoint has newly moved when the viewpoint is moved from one space to another as described above. Objective.
[0022]
[Means for Solving the Problems]
As a first means for solving the problem, an initial 3D image is prepared in advance as a 2D image. For the 2D image, for example, a filter process for suppressing a color such as a “fog (fog) effect” is performed. Keep going. Then, the image that has been subjected to such a filtering process is displayed only once. That is, a 2D image obtained by converting the initial 3D image into a two-dimensional image at the very first time is displayed as a color-suppressed image, and thereafter, the 3D image is sequentially superimposed and displayed on the 2D image.
[0023]
In this case, since the 3D image is displayed in the original color, the portion where the color is suppressed in the screen is not processed as a 3D image, and the portion displayed in the dark color is an object that has already been processed as a 3D image. It is clearly identifiable to the user. This allows the user to know immediately how far the 3D rendering has progressed.
[0024]
As a second means for solving the problem, the content of the 3D frame buffer (three-dimensional image storage means) is subjected to a filtering process having a color suppression effect (for example, a fog effect) similar to that of the first means, and the 3D frame is again obtained. Write back to buffer and display on screen. At that time, the above-described processing is repeated as the object drawing progresses at a predetermined time interval or in the 3D drawing unit (three-dimensional image drawing means). Then, the degree of color suppression is reduced step by step as the number of processing increases, and there is no color suppression when 3D rendering is completed.
[0025]
As a reference example This is achieved by rearranging the data arrangement in the database storing the 3D objects, and sequentially reading out the objects in a desired order, for example, in the order closer to the viewpoint or in the order farther away.
[0026]
In general, when a three-dimensional image is displayed, it is natural that the object is viewed in order from the object closest to the viewpoint. Therefore, the distance between the viewpoint and each object is calculated and displayed in order from the viewpoint. To do this, calculate the distance from the viewpoint position information to each object in the database, sort it in ascending order (or reverse), and change the array position of the object data in the database based on the result. Or set a flag to indicate the order. Then, the data is read out from the database in order according to the arrangement order or the order indicated by the flag and displayed.
[0027]
The first to solve the problem 3 As the means, the coarse or fine data is read out and displayed to the same extent corresponding to each stage for all object data in the order of the coarse shape data of the 3D object to the fine shape data. For this purpose, it is necessary to previously create multi-stage data from a rough shape to a fine shape for one object and register it in the database.
[0028]
The first to solve the problem 4 As a means of 3 Although the purpose is the same as that of the above method, after the object data is read from the database, the shape data roughened to the same extent corresponding to each step is obtained by calculation for all the object data, and it is sequentially converted into a 3D image. indicate. In this case, it is not necessary to store data having a rough shape in the database in advance.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
First, a three-dimensional image display device to which the present invention is applied will be described. In short, this 3D image display device always calculates the distance between the viewpoint position where the walk-through is performed and a place where it can be moved to another space (for example, a door or the like, hereinafter referred to as an entrance). When the distance becomes equal to or smaller than the predetermined value, reading of the data in the space connected to the entrance from the database (hereinafter referred to as predictive reading) is started.
[0030]
This predictive reading process is executed in parallel by processes different from various processes necessary for the process of changing the display state accompanying the movement of the viewpoint by the walkthrough (hereinafter referred to as the viewpoint movement process). . Accordingly, the viewpoint moving process is performed even during the prediction reading.
[0031]
FIG. 3 is a schematic diagram showing an example of a space targeted by the three-dimensional image apparatus to which the present invention is applied, and there are a first space SP1 to a fifth space SP5, each of which is connected to at least one other space. It has a point (entrance). As shown in FIG. 3, the space where the viewpoint PV is currently located (first space SP1) and the other spaces directly or indirectly connected to the first space SP1 are respectively second. Each entrance is described as Ek (SPi, SPj) as space SP2, third space SP3. SPi and SPj describe a space name that can be moved directly through the entrance. If there are multiple entrances where SPi and SPj are the same, they are distinguished by a subscript k of “2” or more. Since the current viewpoint is located in the first space SP1, SPi = SP1.
[0032]
Further, let t be the current time and e (t) be the current position of the viewpoint PV. Then, the distance between the current position e (t) of the viewpoint PV and the space where the viewpoint PV is currently located, that is, all the entrances Ek (SP1, SPj) of the first space SP1 is calculated at each time, and the distance is calculated. With respect to the space SPj in which the value of is less than or equal to a preset threshold value, predictive reading of data in that space is started.
[0033]
However, from the time SPj at a later time point of view When the PV is separated, in other words, when the distance between the viewpoint PV and the entrance Ek (SP1, SPj) is equal to or greater than the threshold, the prediction reading of the data regarding the space SPj is interrupted.
[0034]
By performing the processing as described above, when the viewpoint PV approaches a certain entrance, prediction reading of data in another space connected through the entrance is started. This is based on the fact that the space where the viewpoint PV moves next can be predicted to some extent based on the information that it approaches the entrance, and that space from the time when the viewpoint PV approaches the entrance connected to some other space. As a result, the waiting time for switching the screen when the viewpoint PV actually enters the space is shortened.
[0035]
1 is a block diagram showing an example of the configuration of a 3D image display apparatus to which the present invention is applied, FIG. 2 is a flowchart showing a procedure for predictive reading, and FIG. To do. In FIG. 1, the same reference numerals as those in FIG. 18 referred to in the above description of the conventional example indicate the same or corresponding parts.
[0036]
In FIG. 1, reference numeral 51 denotes a three-dimensional database (hereinafter referred to as a 3D database) that functions as a storage means, and stores a three-dimensional model constituting a three-dimensional space (hereinafter referred to as a 3D object). Has been. However, as shown in the schematic diagram of FIG. 3, the three-dimensional space is divided into a plurality of spaces (in the example of FIG. 3, the space is divided into five spaces of the first space SP1 to the fifth space SP5). However, the data of the 3D object in each space SP1, SP2,... Is managed as one data group.
[0037]
Reference numeral 52 is a reader that functions as a reading unit that reads data from the 3D database 51 in units of one space and transfers the data to the 3D drawing unit 53 that functions as a three-dimensional drawing unit. The reader 52 reads the data related to the space where the viewpoint PV is currently located from the 3D database 51 and gives it to the 3D drawing unit 53 as in the conventional example. However, in the present invention, from the entrance determination unit 58 described later, In accordance with the given instruction, data in another space different from the space where the viewpoint PV is currently located is also read from the 3D database 51 and given to a standby memory 59 described later. These two types of processing can be executed in parallel.
[0038]
In the 3D drawing unit 53, based on the data read by the reader 52, and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating from which position, the three-dimensional graphics calculation is performed for each object. That is, geometric calculation, color calculation, etc. are performed and the result is written in the 3D frame buffer 55 which functions as a three-dimensional image storage means.
[0039]
By repeating the operation of drawing such individual objects in the 3D frame buffer 55, one three-dimensional screen is completed on the 3D frame buffer 55 and displayed on the monitor 56 functioning as display means.
[0040]
Note that information indicating the current position of the viewpoint is given to the viewpoint information setting unit 54 from an input device 57 as an input means. Specifically, for example, the position information of the pointer on the screen of the monitor 56 or the position information obtained from a so-called head mounted display or the like is given to the input device 57, and the viewpoint information setting unit 54 is based on the information. Then, the viewpoint information, that is, the current position and the line-of-sight direction of the viewpoint PV are set in the 3D drawing unit 53.
[0041]
The viewpoint position information input from the input device 57 to the viewpoint information setting unit 54 is provided to the 3D drawing unit 53 as current viewpoint position information, and also to the entrance determination unit 58 that functions as a prediction unit. As described above, the entrance determination unit 58 generates information indicating which entrance is closest to the current position of the viewpoint PV, in other words, which space the viewpoint PV is most likely to move to next. Give to reader 52. Thereby, as described above, the reader 52 reads out the data of the space where the viewpoint PV is currently located from the 3D database 51 and gives it to the 3D drawing unit 53, and at the same time, the viewpoint PV may move next. Data of the space determined to be the largest (hereinafter referred to as the next candidate space) is read from the 3D database 51, and predictive read processing is given to the standby memory 59 functioning as temporary storage means is started.
[0042]
The data given to the standby memory 59 is once held, and then given to the 3D drawing unit 53 when the viewpoint actually moves to that space (next candidate space). However, the distance between any entrance and viewpoint PV Also In other words, the next candidate space has disappeared if it exceeds the predetermined value. Case In this case, the prediction reading process is stopped. Further, when the next candidate space is changed to another space, prediction read processing is performed for the new next candidate space.
[0043]
Next, an actual processing procedure will be described with reference to the flowchart of FIG. 2 and the schematic diagram of FIG. FIG. 4 shows a table in which information on entrances connecting the spaces is registered. Configuration example It is a schematic diagram which shows.
[0044]
As a premise, the 3D database 51 stores the data of the solid model in units of the spaces SP1, SP2,..., And information about the entrances connecting the spaces SP1, SP2,. Is registered as a table.
[0045]
First, as in the conventional example, the data of the space where the viewpoint PV is currently located (hereinafter referred to as the initial space SPx, here referred to as the first space SP1) is read from the 3D database 51 by the reader 52 and monitored. It is displayed on 56 screens (step S11). Then, the entrance determination unit 58 determines whether or not the current position of the viewpoint PV is the next candidate space SPy from the viewpoint position information given from the viewpoint information setting unit 54 (step S12). Note that the next candidate space SPy is a space where the viewpoint PV is likely to move next, as will be described later.
[0046]
If both match at step S12, the process jumps to step S19 described later. If the two do not match, the entrance determination unit 58 determines that all the entrances of the initial space SPx (four entrances E1 (SP1, SP2), E2 in the first space SP1) are based on the current position of the viewpoint PV. (SP1, SP2), E1 (SP1, SP5), E1 (SP1, SP4) are searched in this order (step S13). Then, the entrance determination unit 58 calculates the distance between the current position e (t) of the viewpoint PV and the position of each entrance of the initial space SPx (first space SP1), and whether or not it is equal to or less than a predetermined threshold value. It is determined whether or not (step S14).
[0047]
Specifically, as shown in FIG. 4, since the position coordinates of each entrance are registered in the table in advance, the entrance determination unit 58 uses the coordinate value and the current position e (t) of the viewpoint PV. The Euclidean distance between them is calculated, and an entrance where the distance is equal to or less than a preset threshold is searched. If there are a plurality of entrances, the entrance of the minimum value among them is searched.
[0048]
As a result of the process in step S14, if there is no entrance satisfying the condition, the process returns to step S12. If there is an entrance that satisfies the condition, the entrance is compared with the entrance of the previous determination result (step S15). If the two match, the prediction reading currently being executed is continued (step S20), and then the process returns to step S12. If the two do not match, it means that the next candidate space has changed, and therefore, the prediction reading related to the next candidate space SPy (second space SP2) that has been subject to the prediction reading up to that point is stopped (step S17). ), Predictive readout of a new next candidate space SPz connected to the initial space SPx at the entrance E is started (step S18). Thereafter, the process returns to step S11.
[0049]
Note that if the initial space and the next candidate space coincide with each other in step S12, it means that the viewpoint PV has moved to the next candidate space, so the contents of the standby memory 59 are given to the viewpoint information setting unit 54. And is rendered in the 3D frame buffer 55 (step S19). As a result, the image of the next candidate space is displayed on the screen of the monitor 56 relatively quickly.
[0050]
In the first embodiment of the present invention, the process of predictive reading after step S11 and the like as described above is repeated at predetermined time intervals, so that in the first embodiment of the present invention, the space where the viewpoint position is most likely to move next ( Data of the next candidate space) is read in advance by the reader 52 from the 3D database 51 and stored in the standby memory 59, so when the viewpoint actually moves to another space, the data in that space is transferred to the 3D database. Rather than reading from 51 and drawing in the 3D frame buffer 55, drawing from the standby memory 59 to the 3D frame buffer 55 can be performed more quickly.
[0051]
Next, another example of the three-dimensional image display device to which the present invention is applied will be described. The basic system configuration is the same as the example shown in FIG. Only the prediction method of space is different.
[0052]
In this example, not only the current position e (t) of the viewpoint but also information regarding the direction of the visual field is taken into account, and the next candidate space, that is, the next candidate space is predicted. As in the case of the above example, even when reading of data from the 3D database 51 is started at a certain point in time, if the entrance position no longer exists in the field of view at a certain point after that, the data Reading from the 3D database 51 is interrupted.
[0053]
Although the specific processing will be described below, the basic processing is the same as in the above example, and therefore the schematic diagram of FIG. Will be described with reference to FIG.
[0054]
The entrance determination unit 58 assumes a conical field of view set with an angle width θ with the line-of-sight direction as the central axis, and determines whether or not there is an entrance in the conical field of view. Specifically, as shown in the schematic diagram of FIG. 5, when the line-of-sight vector passing through the current viewpoint position e (t) = (ex, ey, ez) is represented by a three-dimensional vector V (t) To do.
[0055]
First, the entrance determination unit 58 calculates whether or not there is an entrance in an elongated conical field of view having an extent of an angle θ with respect to the three-dimensional vector V (t). If there is no entrance in the field of view, the entrance determination unit 58 does not perform prediction reading assuming that there is no next candidate space. If there are multiple entrances in the field of view, the entrance determining unit 58 selects the entrance with the smallest distance from the viewpoint PV. Then, predictive reading is performed for the entrance.
[0056]
By the way, the position coordinate of a certain entrance is P (x, y, z), and whether or not the entrance exists in the conical field of view of the angle θ is determined by determining the current position e (t) of the viewpoint and the point coordinate P. The determination can be made based on whether or not the angle α between the connecting vector and the three-dimensional vector V (t) (hereinafter referred to as V) is θ or less.
[0057]
Here, the angle α is obtained as an outer product of the three-dimensional vectors Q and V connecting e and P.
[0058]

[0059]
When a plurality of entrances satisfying these conditions are found, the one with the smallest vector Q length is adopted as the next candidate space. If such a calculation is performed for all entrances in step S13 of the flowchart of FIG. 3 described above, it is possible to find an entrance that exists in the field of view at an angle θ with respect to the viewpoint position and viewpoint direction at a certain time. .
[0060]
By the way, in the above example, at the time of switching the screen when the viewpoint moves from one space to another space, predictive reading in which data for displaying a new space is read from the 3D database 51 to the standby memory 59 in advance. This is a method for shortening the time required for writing the necessary data to the 3D frame buffer 55 from the time when it is determined that the viewpoint has moved from one space to another.
[0061]
However, even if the data in the standby memory 59 is moved to the 3D drawing unit 53 and drawn in the 3D frame buffer 55, it takes a certain amount of time until the image is actually displayed on the screen of the monitor 56. In the meantime, nothing is displayed on the screen, or the display state up to that point is maintained as a still image, so that the user is forced to have a hand-held state. Under these circumstances, in each of the following embodiments of the present invention, the display state until a complete 3D image is displayed on the screen of the monitor 56 is devised to maintain the user's handheld state. We are trying to solve the problem.
[0062]
[First Embodiment]
In the first embodiment of the present invention, a 2D image obtained by previously converting an initial 3D image into a two-dimensional image is prepared. The 2D image (initial 3D image) includes, for example, a “fog (fog) effect” described later. Performs processing to suppress colors using filter processing. Then, an image using the fog effect is displayed only in the first time. In other words, the 2D image (the image obtained by converting the initial 3D image into a two-dimensional image) is displayed with the color suppressed only at the first display, and then the 3D image is sequentially overwritten on the 2D image. .
[0063]
In such a method, since the 3D image is displayed in the original color, 3D drawing is unprocessed in the part where the color is suppressed in the screen, and 3D drawing is already in the part displayed in the dark color The user can clearly identify that the object is a finished object. This allows the user to immediately recognize how much 3D rendering is progressing.
[0064]
By the way, as a practical example of the fog effect, the following calculation method can be used. For example, it is assumed that one pixel in the 3D frame buffer 55 (see FIG. 6) is expressed by three primary colors (red (R), green (G), and blue (B)). In this case, for example, using a constant k that takes a value in the range of “0” to “1”,
r = R * k, g = G * k, b = B * k
If a pixel value r, g, b is obtained by calculation and this is used as one pixel (r, g, b), a simple fog effect can be obtained.
[0065]
Of course, it is possible to use other processing methods as long as the operation can easily obtain a pixel value lower than the original pixel value by a simple calculation in addition to the fog effect as described above. Needless to say.
[0066]
Hereinafter, a specific example will be described with reference to a block diagram of FIG. 6 showing a configuration example of the first embodiment and a schematic diagram of FIG. 7 showing a display state.
[0067]
In FIG. 6, reference numeral 51 is a three-dimensional database (3D database), and the three-dimensional image forming the three-dimensional space, that is, the data of the object is stored. However, in the first embodiment, 2D image data obtained by two-dimensionalizing an initial 3D image of each space viewed from each entrance is also stored.
[0068]
Reference numeral 52 is a reader for reading data regarding the space where the viewpoint PV is currently located from the 3D database 51. Data read from the 3D database 51 by the reader 52 is provided to the 3D drawing unit 53. When the space is switched, 2D image data corresponding to the initial 3D image is read from the 3D database 51 by the reader 52 and transferred to the 2D drawing unit 62.
[0069]
In the 3D drawing unit 53, based on the data read by the reader 52 and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating from which position the object is viewed, geometric calculation, color calculation, etc. And write the result into the 3D frame buffer 55. The image written in the 3D frame buffer 55 is sent to the monitor 56 and displayed.
[0070]
The 2D drawing unit 62 draws, in the 3D frame buffer 55, 2D image data corresponding to the initial 3D image given when the space is switched. The 2D drawing unit 62 is connected with a fog parameter setting unit 71 that functions as a filter strength setting unit. In the fog parameter setting unit 71, an arbitrary fog parameter having a value in the range of “0” or more and “1” or less can be set.
[0071]
The operation of the first embodiment of the present invention is as follows. Assuming that the viewpoint is located in a certain space, the 3D rendering unit 53 performs 3D rendering according to the position information given from the viewpoint information setting unit 54 by reading the data read from the 3D database 51 by the reader 52 as in the conventional example. By drawing in the frame buffer 55, an image in the space is displayed on the screen of the monitor 56.
[0072]
When the space is switched from such a state, data for displaying the initial 3D image is read out from the 3D database 51 by the reader 52 in accordance with the viewpoint information given from the viewpoint information setting unit 54. The data for displaying the initial 3D image includes 2D image data, and is transferred to the 2D drawing unit 62 via the 3D frame buffer 55.
[0073]
By the way, as described above, the fog parameter setting unit 71 is previously set with a fog effect parameter, that is, a fog parameter k (0 ≦ k ≦ 1). The 2D drawing unit 62 multiplies each pixel value (R, G, B) of the 2D image by the fog parameter k set in the fog parameter setting unit 71 to obtain a new pixel value (r, g, b). The result is written to the 3D frame buffer 55. The image written in the 3D frame buffer 55 is displayed on the screen of the monitor 56. This display state is shown in FIG. Here, a 2D image in which the color is suppressed according to the fog parameter k set by the fog parameter setting unit 71 is displayed.
[0074]
Next, the reader 52 first reads the data of one object from the top of the 3D database 51 and transfers it to the 3D drawing unit 53. The 3D drawing unit 53 performs a three-dimensional drawing calculation based on the viewpoint position information set in advance as an initial state when the space is switched and the object data read from the 3D database 51, and performs a 3D frame buffer 55. Draw on When the drawing of one object in the 3D frame buffer 55 is completed in this way, only the image of the object is clearly displayed on the screen of the monitor 56 as shown in FIG.
[0075]
Thereafter, similarly, the reader 52 sequentially reads the data of other objects from the 3D database 51 and draws them in the 3D frame buffer 55, and eventually reads all the data in one space and draws it in the 3D frame buffer 55. . In this state, a clear initial 3D image is displayed on the screen of the monitor 56 as shown in FIG.
[0076]
As described above, in the first embodiment of the present invention, when the viewpoint position moves to another space and the space is switched, the two-dimensionalization is performed until the initial 3D image is displayed. An image in which the color is further suppressed by the fog parameter is displayed, and then an initial 3D image to be actually displayed is sequentially superimposed and displayed. Therefore, the user can easily recognize how far the 3D image drawing has progressed.
[0077]
[Second Embodiment]
Next, a second embodiment will be described. In the second embodiment, a filter process for color suppression similar to that in the first embodiment described above is performed on data read from a database. (For example, a fog effect) is applied, and the screen is returned to the 3D frame buffer 55 and displayed again. At this time, the above-described processing is repeated with a predetermined time interval or with the progress of object drawing in the 3D drawing unit 53. At the same time, as the number of color suppression processes progresses, the fog parameter is gradually changed from “0” or a value close to “0” to “1”, and the color suppression process is not performed when 3D rendering is completed. The state, that is, the fog parameter is set to “1”. In other words, the fog parameter k is initially set to “0”, gradually increased as the number of processes proceeds, and controlled to be “1” at the end.
[0078]
According to the second embodiment, the display of the 3D drawing result is initially light in color, and then the screen effect is obtained in which the color becomes darker as 3D drawing proceeds. As a result, the user can intuitively grasp how much the 3D drawing is progressing.
[0079]
Hereinafter, a specific example will be described with reference to a block diagram of FIG. 8 showing a configuration example of the second embodiment and a schematic diagram of FIG. 9 showing a display state.
[0080]
In FIG. 8, reference numeral 51 is a three-dimensional database (3D database), and the three-dimensional image forming the three-dimensional space, that is, the data of the object is stored. It is the same.
[0081]
Reference numeral 52 is a reader for reading out data related to the space where the viewpoint is currently located from the 3D database 51. Data read from the 3D database 51 by the reader 52 is provided to the 3D drawing unit 53.
[0082]
In the 3D drawing unit 53, based on the data read by the reader 52 and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating from which position the object is viewed, geometric calculation, color calculation, etc. And write the result into the 3D frame buffer 55. The image written in the 3D frame buffer 55 is once transferred to the 2D drawing unit 62.
[0083]
The 2D drawing unit 62 is connected to a fog parameter updating unit 72 that functions as a filter strength changing unit. The 2D drawing unit 62 applies color suppression processing to the image drawn in the 3D frame buffer 55 according to the fog parameter set at that time in the fog parameter update unit 72, and draws the result in the 3D frame buffer 55 again. To do. The fog parameter updating unit 72 updates the fog parameter k step by step in the range of “0” to “1”.
[0084]
The operation of the second embodiment of the present invention is as follows. Assuming that the viewpoint is located in a certain space, the 3D rendering unit 53 performs 3D rendering according to the position information given from the viewpoint information setting unit 54 by reading the data read from the 3D database 51 by the reader 52 as in the conventional example. By drawing in the frame buffer 55, an image in the space is displayed on the screen of the monitor 56.
[0085]
When the space is switched from such a state, data for displaying an initial 3D image is read from the 3D database 51 by the reader 52 in accordance with the viewpoint information given from the viewpoint information setting unit 54, and the viewpoint information setting unit 54 Thus, the image is drawn in the 3D frame buffer 55, and the result is transferred to the 2D drawing unit 62. Specifically, the reader 52 first reads data of one object from the top of the 3D database 51 and transfers it to the 3D drawing unit 53. The 3D drawing unit 53 performs a three-dimensional drawing calculation based on the viewpoint position information set in advance as an initial state when the space is switched and the object data read from the 3D database 51, and performs a 3D frame buffer 55. Draw on
[0086]
By the way, the 3D image drawn in the 3D frame buffer 55 is transferred to the 2D drawing unit 62 at every predetermined time interval or whenever one object is drawn in the 3D frame buffer 55. Here, as an example, it is assumed that the data on the 3D frame buffer 55 is transferred to the 2D drawing unit 62 based on the number of objects that have been drawn on the 3D frame buffer 55.
[0087]
A fog parameter update unit 72 is connected to the 2D drawing unit 62. The fog parameter update unit 72 sequentially changes the fog parameter k as follows. That is, the fog parameter k that is initially set in the fog parameter update unit 72 is set to k0. Further, the update constant is d (here, d = (1−k0) / N is set), and the 3D drawing unit 53 draws one object, and the result is transferred to the 2D drawing unit 62. Each time, the fog parameter k is updated as follows.
[0088]
k ← k + d
[0089]
By updating the fog parameter in this way, the initial value starts from k = k0, and k = 1 when all objects are processed. The fog effect is exhibited using the fog parameter k. Specifically, when the 3D drawing unit 53 draws one object, the 2D drawing unit 62 once reads the content of the 3D frame buffer 55 at the update timing, and the pixel values (R, G, B) of the image ) Is multiplied by the fog parameter k updated by the fog parameter updating unit 72 to convert it to a pixel value (r, g, b) and then written back to the 3D frame buffer 55.
[0090]
When the drawing of the first one object to the 3D frame buffer 55 is completed in this way, only the image of the first one object has its color suppressed as shown in FIG. 9 (a). It is displayed on the screen of the monitor 56 with an effect.
[0091]
Similarly, the reader 52 sequentially reads the data of other objects from the 3D database 51 and draws them in the 3D frame buffer 55. When drawing of the next other object in the 3D frame buffer 55 is completed, FIG. As shown in (b), the image of the first object and the next object has a fog effect with reduced color but is darker than when only the first object was displayed. The color is displayed on the screen of the monitor 56.
[0092]
Eventually, reading of all data in one space and drawing to the 3D frame buffer 55 are completed. In this state, a clear initial 3D image is displayed on the screen of the monitor 56 as shown in FIG.
[0093]
As described above, in the second embodiment of the present invention, when the viewpoint position moves to another space and the space is switched, the initial 3D image is displayed until the complete state is displayed. Each time an individual object is displayed, it is displayed in stages from a state in which the color is suppressed by a fog parameter to a complete state. Therefore, the user can recognize how much 3D drawing is progressing.
[0094]
[ Reference example ]
Reference example Then, by manipulating a database storing 3D objects, the objects are read out in an optimal order.
[0095]
In general, when a three-dimensional image is drawn, a natural feeling can be obtained by displaying the three-dimensional image so that the object closer to the viewpoint is viewed in order from the object farther away. Therefore, Reference example Then, in principle, the distance between the viewpoint and each object is calculated in advance, and each object is 3D drawn in the order from the viewpoint. However, it goes without saying that each object may be 3D drawn in order from the viewpoint in order to obtain a special screen effect, for example.
[0096]
Specifically, it calculates the distance between each object in the database and the viewpoint position according to the viewpoint position information, sorts it in ascending order (or reverse), and based on the result, array of the object data in the database Or set a flag indicating the order. When 3D data is read from the 3D database, 3D drawing is performed by reading from the top of the database or in order from the one with the smallest order flag.
[0097]
Less than, Reference example FIG. 10 is a block diagram showing a configuration example of FIG. 10, a schematic diagram of FIG. 11 showing a conventional display state, and Reference example The display state will be specifically described with reference to the schematic view of FIG.
[0098]
In FIG. 10, reference numeral 51 denotes a three-dimensional database (3D database), and the three-dimensional image constituting the three-dimensional space, that is, the data of the object is stored. It is the same. The 3D database 51 is connected to a sorter 73 described later.
[0099]
Reference numeral 52 is a reader for reading data regarding the space where the viewpoint PV is currently located from the 3D database 51. Data read from the 3D database 51 by the reader 52 is provided to the 3D drawing unit 53.
[0100]
In the 3D drawing unit 53, based on the data read by the reader 52 and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating from which position the object is viewed, geometric calculation, color calculation, etc. And write the result into the 3D frame buffer 55. The image written in the 3D frame buffer 55 is sent to the monitor 56 and displayed.
[0101]
Here, the sorter 73 functioning as a classification unit will be described. When the viewpoint position information is expressed as a coordinate value in the three-dimensional space such as (ex, ey, ez), the sorter 73 displays the viewpoint position information given from the viewpoint information setting unit 54 and each object data in the 3D database 51. And In comparison, numbers are assigned in ascending order of distance from the viewpoint position.
[0102]
Specifically, it is as follows. Each object in the 3D database 51 is Oj (j = 1 to N). A point coordinate constituting the object Oj is set to (xi, yi, zi) (where i is a point number), and a boundary box surrounding the object Oj, that is, the position of a virtual rectangular parallelepiped including the object Oj is calculated. The boundary box can be expressed by two points a and b in the three-dimensional space. If these coordinates are (xa, ya, za), (xb, yb, zb), a and b are as follows: Is required.
[0103]
xa = Min (xi), ya = Min (yi), za = Min (zi)
xb = Max (xi), yb = Max (yi), zb = Max (zi)
[0104]
Here, the Min and Max operations are calculations for obtaining the minimum and maximum values over all point coordinates in the object Oj.
[0105]
For the center of gravity (xgj, ygj, zgj) of the boundary box, the midpoint of points a and b may be obtained. Accordingly, the distance Dj from the viewpoint position to the center of gravity of each object Oj is obtained as follows.

[0106]
This Dj is calculated for all objects, and the arrangement of the object data in the 3D database 51 is rearranged in ascending order from the result. The rearrangement can be easily performed by using a known technique such as a quick sort. After performing this process, the reader 52 reads out the object from the top of the 3D database 51 and performs 3D drawing, so that it is possible to display on the screen in order from the object at a position closer to the viewpoint.
[0107]
like this Reference example The operation of is as follows. Assuming that the viewpoint is located in a certain space, the 3D rendering unit 53 performs 3D rendering according to the position information given from the viewpoint information setting unit 54 by reading the data read from the 3D database 51 by the reader 52 as in the conventional example. It is assumed that an image in the space is displayed on the screen of the monitor 56 by drawing in the frame buffer 55.
[0108]
When the space is switched from such a state, the sorter 73 rearranges the object data in the 3D database 51 in the order from the viewpoint position according to the viewpoint information given from the viewpoint information setting unit 54 as described above. After performing this processing, data for displaying the initial 3D image is read from the 3D database 51 by the reader 52, drawn by the 3D drawing unit 53 in the 3D frame buffer 55, and displayed on the screen of the monitor 56.
[0109]
For example, in the prior art, as shown in FIGS. 11 (a), (b) and (c), it was unknown from which object in the space the object is displayed on the monitor 56. Reference example Accordingly, as shown in FIGS. 12A, 12B, and 12C, the objects close to the viewpoint position are displayed on the screen of the monitor 56 in order.
[0110]
If there is only one entrance to a certain space, the position of the viewpoint of the initial 3D image in that space is known, so the data of each object is preliminarily determined by the sorter 73 (initial 3D image). The images may be rearranged in order from the closest (image viewpoint position). However, as for the space through which a plurality of entrances are connected, it is of course possible to perform sorting by the sorter 73 each time it becomes necessary to display the space, or to perform sorting in advance corresponding to each entrance. is there.
[0111]
in this way Reference example Then, when the viewpoint position moves to another space and the space is switched, the initial 3D image is displayed gradually from the side closer to the viewpoint position. At the same time, it is possible to recognize whether or not the user is on the screen, and the screen is displayed step by step from the close-up view on the screen.
[0112]
[No. 3 Embodiment of
Next 3 The embodiment will be described. This first 3 In this embodiment, fine shape data is sequentially read from the rough shape data of the 3D object and displayed. For this reason, it is necessary to previously create data from a rough shape to a fine shape for each object in multiple stages and register it in the database. However, the user can know in advance the rough layout and shape of the 3D world, and is also given the pleasure of imagining the final shape from the rough shape.
[0113]
The following 3 A specific example will be described with reference to a block diagram of FIG. 13 showing a configuration example of the embodiment and a schematic diagram of FIG. 15 showing a display state.
[0114]
In FIG. 13, reference numeral 51 denotes a three-dimensional database (3D database), and the three-dimensional image constituting the three-dimensional space, that is, the data of the object is stored. It is the same. Although details will be described later in the 3D database 51, a LOD (Level-Of-Detail) creation unit 74 that functions as a thinning means for creating data from a rough shape to a fine shape in advance in multiple stages for a 3D object. Is connected. This LOD creation unit 74 automatically creates multi-level object data from coarse solid data to fine solid data for each object in the 3D database 51 in advance before starting 3D drawing, and stores the original data in the 3D database 51. And register additional.
[0115]
Reference numeral 52 is a reader for reading data regarding the space where the viewpoint PV is currently located from the 3D database 51. Data read from the 3D database 51 by the reader 52 is provided to the 3D drawing unit 53.
[0116]
In the 3D drawing unit 53, based on the data read by the reader 52 and according to the viewpoint information given from the viewpoint information setting unit 54, that is, information indicating from which position the object is viewed, geometric calculation, color calculation, etc. And write the result into the 3D frame buffer 55. The image written in the 3D frame buffer 55 is sent to the monitor 56 and displayed.
[0117]
Such a first aspect of the present invention 3 The operation of this embodiment will be specifically described with reference to the schematic diagram of FIG. 14 showing the table generation method by the LOD creation unit 74 and the schematic diagram of FIG. 15 showing the display state.
[0118]
Before starting the 3D drawing, first, the LOD creation unit 74 automatically creates multi-level object data for each object in the 3D database 51 from coarse to fine 3D data in advance, and stores the original data in the 3D database 51. And register it as well.
[0119]
The processing by the LOD creation unit 74 is as follows. It is assumed that the data constituting one object in the 3D database 51 has a format as shown in the schematic diagram of FIG. Here, the polygon table (L-TABLE) in which the surface (polygon) data constituting the object is registered, the edge table (E-TABLE) in which the edge data constituting the surface data is registered, and the point data constituting the edge data are It has a hierarchical structure called a registered point table (P-TABLE).
[0120]
Assume that the object is composed of polygon 1, polygon 2,... Polygon P. The LOD creation unit 74 mechanically thins out even-numbered polygons from the L-TABLE and writes a series of polygons 1, polygons 3... Into another polygon table (L-TABLE 2). Next, for each polygon data written in the L-TABLE 2, the LOD creation unit 74 searches for edge data corresponding to the polygon data. For example, if the sides constituting the polygon 1 are e1, e2, e3,..., The even-numbered sides are thinned out in the same manner as described above to create a new series e1, e3,. Write. Therefore, the term of polygon 1 in L-TABLE 2 is sides e1, e3,.
[0121]
After the above operation is completed, only the edge data that appears in the L-TABLE 2 is registered in the new edge table E-TABLE 2. Thereafter, only point data appearing in E-TABLE 2 is registered in a new point table P-TABLE 2. When the LOD creation unit 74 creates L-TABLE 2, E-TABLE 2 and P-TABLE 2 in such a procedure, the new object represented by these three tables represents the original object in about half the plane. It becomes a rough solid model.
[0122]
In order to automatically create a model with multiple levels of roughness, if the same process is repeated by appropriately setting the amount of data jumping, for example, the (m + 1) level of roughness including the original model can be obtained. If a model needs to be created, the data jumping amount is first set to m, and thereafter, m-1, m-2,...
[0123]
When a plurality of stepwise coarse models of one object are newly created by performing the processing as described above, the LOD creation unit 74 inserts these data at the head of the 3D database 51 and registers them. By performing such processing, when the reader 52 reads the data of each object, it first reads the data of the coarsest model with respect to each object, and coarsely reads each object as shown in FIG. 15 (a). Display as an image. Next, the reader 52 reads the second coarsest data for each model, and displays each object as shown in FIG. 15 (b) as a slightly fine image. In the same manner, the data of the coarse model are sequentially read out step by step and displayed on the monitor 56. Since the original data of each object is stored in the latter half of the 3D database 51, the rough model on the monitor overwrites the original model as shown in Fig. 15 (c) at the final stage. Is done.
[0124]
Thus, the present invention 3 In this embodiment, when the viewpoint position moves to another space and the space is switched, each object constituting the initial 3D image is first displayed as a very coarse image, and sequentially becomes a fine image. Since the original image is displayed at the end after being overwritten, the possibility of forcing the user to hold the camera in a dull state decreases.
[0125]
[No. 4 Embodiment of
By the way, 3 In this embodiment, the above-described capacity is required by the 3D database 51 that stores 3D data that requires a large amount of data. Therefore, if there is no room in the 3D database 51 capacity, 3 The following effects can be obtained which are almost the same as those of the first embodiment. 4 The embodiment is preferred.
[0126]
First 4 In this embodiment, after reading object data from the database, a rough shape data is obtained by calculation, and a method of sequentially displaying it is adopted. Therefore, it is not necessary to prepare rough shape data in advance and store it in the database.
[0127]
The following 4 A specific example will be described with reference to the block diagram of FIG. 16 showing a configuration example of the embodiment. As shown in the block diagram of FIG. 4 In this embodiment, the LOD creation unit 74 is not connected to the 3D database 51 but is located between the reader 52 and the 3D drawing unit 53. Other configurations are shown in FIG. 3 This is the same as the embodiment.
[0128]
Such a first aspect of the present invention 4 The operation of this embodiment is as follows. Here, as an example, a case will be described in which models with a total of (m + 1) stages of roughness are displayed.
[0129]
First, m is set as a roughness parameter in the LOD creation unit 74. When the original data of one object read from the 3D database 51 by the reader 52 is input to the LOD creation unit 74, the LOD creation unit 74 3 The same processing as in the above embodiment is performed to automatically create new coarse object tables (L-TABLE 2, E-TABLE 2 and P-TABLE 2), and the data described in these tables are stored in one The data is transferred to the 3D drawing unit 53 as object data. The 3D drawing unit 53 draws the model having the roughness m in the 3D frame buffer 55. When the reader 52 detects the last object from the 3D database 51, the roughness parameter is set to m-1 and the same processing as described above is performed again. As a result, this time, a three-dimensional model with roughness (m−1) is automatically created by the LOD creation unit 74, 3D-drawn in the 3D frame buffer 55, and displayed on the monitor 56.
[0130]
By repeating the above process, the original image is displayed on the screen of the monitor 56 if a model with zero roughness is finally created. This number 4 The display state of the embodiment is 3 This is the same as the display state of the embodiment.
[0131]
Thus, the present invention 4 In the embodiment of the 3 As in the above embodiment, when the viewpoint position moves to another space and the space is switched, each object constituting the initial 3D image is first displayed as a very rough image, and sequentially refined. Since the original image is finally displayed after being overwritten on the image, the possibility of forcing the user to hold the camera in a dull state decreases.
[0132]
In addition, the aforementioned first 3 The first embodiment and this 4 The difference from this embodiment is that coarse image data is stored in the database in advance or is created each time it is actually displayed, so depending on the capacity of the database, the degree of image processing speed, etc. It is desirable to use either.
[0133]
【The invention's effect】
As described above in detail, according to the present invention, the user can obtain some information related to the rendered image from a screen prepared in advance until the rendering of the three-dimensional image is completed. In particular, if the screen is an image obtained by two-dimensionalizing the final result of the image currently being calculated for drawing, the next screen can be known in advance.
[0134]
Furthermore, when using a filter process that provides a screen effect such as the fog effect gradually fading, the user can intuitively understand how much 3D rendering has progressed. Moreover, since the scene of another space appears gradually from the scene of one space, a user's psychological burden is reduced.
[0135]
Furthermore, information such as what the next 3D screen can be seen and what can be seen is given priority.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration example of a three-dimensional image display apparatus to which the present invention is applied.
FIG. 2 is a flowchart showing a procedure for predictive reading of the apparatus of FIG. 1;
FIG. 3 is a schematic diagram illustrating an example of a space targeted by a three-dimensional image display device to which the present invention is applied.
FIG. 4 is a schematic diagram illustrating a configuration example of a table in which entrance information is registered.
FIG. 5 is a schematic diagram showing a relationship between a line-of-sight vector and an entrance position.
FIG. 6 is a block diagram illustrating a configuration example of the first exemplary embodiment of the present invention.
FIG. 7 is a schematic diagram of a screen display according to the first embodiment.
FIG. 8 is a block diagram illustrating a configuration example of a second exemplary embodiment of the present invention.
FIG. 9 is a schematic diagram of screen display according to the second embodiment.
FIG. 10 Reference example It is a block diagram which shows the example of a structure.
FIG. 11 is a schematic diagram of a conventional screen display.
FIG. Reference example It is a schematic diagram of a screen display.
FIG. 13 shows the first of the present invention. 3 It is a block diagram which shows the structural example of this embodiment.
FIG. 14 is a schematic diagram illustrating a table generation method by an LOD creation unit.
FIG. 15 3 The embodiment and the first 4 It is a schematic diagram of the screen display of the embodiment.
FIG. 16 shows the first of the present invention. 4 It is a block diagram which shows the structural example of this embodiment.
FIG. 17 is a schematic diagram of a three-dimensional space assumed by the present invention.
FIG. 18 is a block diagram illustrating a conventional system configuration example.
[Explanation of symbols]
51 3D Database
52 reader
53 3D drawing part
54 Viewpoint information setting section
55 3D frame buffer
56 Monitor
57 Input devices
58 Entrance judgment section
59 Standby memory
62 2D drawing part
63 2D frame buffer
64 switcher
71 Fog parameter setting section
72 Fog parameter update unit
73 Sorter
74 LOD creation department

Claims (8)

In a 3D image display method for displaying a 3D image based on data stored in a storage means,
Predetermining initial conditions when reading the data stored in the storage means and displaying it as a three-dimensional image,
The three-dimensional image displayed according to the initial condition is two-dimensionalized, and a two-dimensional initial image subjected to a predetermined filtering process is created in advance,
When the data stored in the storage means is read out and displayed as a three-dimensional image, the filtered two-dimensional initial image is displayed first, and the three-dimensional image is superimposed on the two-dimensional initial image. 3D image display method characterized by the above. In a 3D image display method for displaying a 3D image based on data stored in a storage means,
When the data stored in the storage means is read out and displayed as a three-dimensional image, a predetermined filtering process is performed step by step so that the data gradually becomes weaker as the data is read out from the storage means. A three-dimensional image display method characterized in that display is performed a plurality of times and the data read from the storage means is displayed without performing the filtering process. In a 3D image display method for displaying an entire 3D image by sequentially displaying 3D images of individual 3D models based on data of a plurality of 3D models stored in the storage means,
For each of the data of the plurality of three-dimensional models, a plurality of models in which the degree of data thinning is changed in stages are registered in advance in the storage unit,
When reading the data stored in the storage means and displaying it as a three-dimensional image, it is changed step by step from data with a large degree of thinning to data with a small degree, and in each step, all three-dimensional models are changed to each step. A three-dimensional image display method characterized in that data corresponding to the degree of thinning is read from the storage means and displayed, and finally data not thinned is read from the storage means and displayed. In a 3D image display method for displaying an entire 3D image by sequentially displaying 3D images of individual 3D models based on data of a plurality of 3D models stored in the storage means,
When reading out the data stored in the storage means and displaying it as a three-dimensional image, the level of data thinning is changed stepwise from large to small, and each solid model corresponds to each step in each step. A three-dimensional image display method characterized in that data is read out from the storage means and displayed while being thinned to the extent that the data is finally read out from the storage means without being thinned out. Storage means for storing data for displaying a three-dimensional space;
Data reading means for reading data for displaying a three-dimensional space from the storage means;
3D image storage means for storing 3D images;
Three-dimensional drawing means for drawing and storing the data read from the storage means by the data reading means in the three-dimensional image storage means;
A three-dimensional image display device comprising: display means for displaying an image drawn in the image storage means;
Two-dimensional image drawing means for drawing a two-dimensional image on the three-dimensional image storage means while performing a predetermined filtering process;
Filter strength setting means for setting the strength of the predetermined filter processing by the two-dimensional drawing means,
The storage means stores a two-dimensional initial image obtained by converting a three-dimensional image displayed in accordance with a predetermined initial condition as a condition for reading out data stored in the storage means and displaying the data as a three-dimensional image. And
The reading means first reads the data of the two-dimensional initial image stored in the storage means and gives the data to the two-dimensional drawing means, and then reads the data for displaying the three-dimensional space from the storage means. Giving to the three-dimensional drawing means,
The two-dimensional drawing means performs the filtering process of the intensity set in the filter intensity setting means on the data of the two-dimensional initial image given from the reading means, and draws the data in the three-dimensional image storage means.
The three-dimensional drawing unit draws the data for displaying the three-dimensional space given from the reading unit by superimposing the data on the two-dimensional initial image drawn by the two-dimensional drawing unit in the three-dimensional image storage unit. A three-dimensional image display device characterized in that it is well-developed. Storage means for storing data for displaying a three-dimensional space;
Data reading means for reading data for displaying a three-dimensional space from the storage means;
3D image storage means for storing 3D images;
Three-dimensional drawing means for drawing and storing the data read from the storage means by the data reading means in the three-dimensional image storage means;
A three-dimensional image display device comprising: display means for displaying an image drawn in the image storage means;
Two-dimensional image drawing means for drawing a two-dimensional image on the three-dimensional image storage means while performing a predetermined filtering process;
Filter strength changing means for changing the set value of the strength of the predetermined filter processing by the two-dimensional drawing means to “0” step by step at each predetermined timing;
The two-dimensional drawing unit has a set value set by the filter strength setting unit for the three-dimensional image drawn in the three-dimensional image storage unit by the three-dimensional drawing unit at each predetermined timing. A three-dimensional image display device, wherein the three-dimensional image storage means performs drawing on the three-dimensional image storage means. Storage means for storing data of a plurality of three-dimensional models for sequentially displaying a three-dimensional image of each three-dimensional model;
Data reading means for sequentially reading out data for displaying a three-dimensional space in units of individual stereo models from the storage means;
3D image storage means for storing 3D images;
Three-dimensional drawing means for drawing and storing the data read from the storage means by the data reading means in the three-dimensional image storage means;
A three-dimensional image display device comprising: display means for displaying an image drawn in the image storage means;
For each of the data of the plurality of three-dimensional models stored in the storage means, comprising a thinning means for creating and registering in the storage means a plurality of models in which the degree of data thinning is changed in stages,
The readout means reads out from the storage means the data of the degree of thinning corresponding to each stage for all the three-dimensional models at each stage while changing the data in stages from the data with the largest degree of thinning out to the smallest data. A three-dimensional image display device characterized in that data that has not been thinned out is read out from the storage means. Storage means for storing data of a plurality of three-dimensional models for sequentially displaying a three-dimensional image of each three-dimensional model;
Data reading means for sequentially reading out data for displaying a three-dimensional space in units of individual stereo models from the storage means;
3D image storage means for storing 3D images;
Three-dimensional drawing means for drawing and storing the data read from the storage means by the data reading means in the three-dimensional image storage means;
A three-dimensional image display device comprising: display means for displaying an image drawn in the image storage means;
For each of the data of the plurality of three-dimensional models read by the reading means from the storage means, the degree of data thinning is gradually changed to “0” by a degree corresponding to each stage, and the three-dimensional processing is performed. A three-dimensional image display device comprising thinning means for giving to a drawing unit.

Images