JPH07306957A - Shadow line processing method for two-dimensional drawing - Google Patents

Abstract

PURPOSE:To omit the labor of indication and input by simultaneously performing the shadow line processing with a sheet as the unit at the time of insertion, deletion, height change, or the like of plural graphics. CONSTITUTION:When plural graphics are displayed on a layer L to generate a two-dimensional drawing, plural sheets S1 to S3 which are spread in parallel with the layer L and have reference points at arbitrary height above the layer L are defined, and at least one graphic is plotted in an arbitrary position of each sheet, and graphics on the sheet, which has the higher reference point to the layer L, out of at least two sheets of plural sheets S1 to S3 are preferentially displayed on the layer L.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing hidden lines in a two-dimensional drawing suitable for use in creating a two-dimensional drawing by a graphic processing device such as a computer aided design (CAD) system.

[0002]

2. Description of the Related Art As a conventional hidden line processing method, for example, a method described in Japanese Patent Laid-Open No. 3-95691 is known. In this method, as shown in FIG. The graphic data a and the broken-line graphic data c of the same shape having a higher display priority than that of the solid-line graphic data a are generated, and the display priority between the solid-line graphic data a and the broken-line graphic data c is set. The mask graphic data b is generated and the hidden line processing is performed according to the display priority.

As a conventional hidden line processing method, for example, a method described in Japanese Patent Laid-Open No. 64-88693 is also known. In this method, as shown in FIG. , By giving a master-slave relationship of which is upper or lower, a part of the slave figure S inside the master figure M is set with an implicit bit.
Hidden line processing is performed by turning it OFF, and there is no dashed line processing.

Further, as a conventional hidden line processing method, FIG.
A method such as that shown in is also known. In this method, height information (Z value) indicating the height of each figure of each part is given, and the hidden line is processed by giving priority to the one having the highest height. There is.

[0005]

However, in the conventional method described above, in the first method, it becomes difficult to change and manage the priority when the figures are crowded, and the priority is increased each time the figure is increased. There is also a problem that it is necessary to check, and in the second method, since it is necessary to instruct the master-slave relationship every time hidden line processing is performed, there is a problem that it takes time to instruct if there are many figures, and In the third method, since the height has to be input for each part, there is a problem in that this also takes time and labor for inputting.

Further, in the third method, since each figure is managed with only one Z value, there is a problem that hidden lines cannot be processed in the case of an inclined figure even if the Z value is the same.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hidden line processing method that advantageously solves the above problems, and the first two-dimensional drawing hidden line processing method of the present invention is When displaying a plurality of figures on a layer to create a two-dimensional drawing, define a plurality of sheets that extend in parallel with the layer and have reference points at arbitrary height positions above the layer. , Drawing at least one figure at an arbitrary position on each of the sheets, and drawing the figure on at least two sheets of the plurality of sheets, in which the height of the reference point with respect to the layer is higher. The figure on the sheet is preferentially displayed on the layer.

A second method for processing hidden lines in a two-dimensional drawing according to the present invention, in which a plurality of figures are displayed on a layer to create a two-dimensional drawing, has an arbitrary inclination with respect to the layer, and Define a plurality of sheets having a reference point at a position at an arbitrary height above, draw at least one figure at an arbitrary position on each of the sheets, and draw at least two of the plurality of sheets. As for the figure on the sheet, the figure having a higher height for the layer obtained based on the height of the reference point of the sheet with respect to the layer, the inclination of the sheet, and the position of the figure on the sheet is prioritized. And is displayed on the layer.

In the first and second methods, the shape data of each figure drawn on the sheet may be saved by adding the data of the figure name as an attribute.

Further, in the first and second methods, when a plurality of figures are drawn on the same sheet, the figures are distinguished by using the data of the name added to each figure. , Give one or more kinds of master-slave relations among these plural figures, and register the master-slave relation,
The plurality of graphics may be displayed on the layer based on the registered master-slave relationship.

On the other hand, according to a third method for processing hidden lines in a two-dimensional drawing of the present invention, when a plurality of figures are displayed on a layer to create a two-dimensional drawing, the two-dimensional drawing extends in parallel with the layer and the layer. A plurality of planes having a reference point at a position of arbitrary height above is defined without limiting the area, and different colors are associated with the planes, and the planes are arranged at arbitrary positions on the planes. Draw at least one figure in a color corresponding to, among the plurality of planes, the figure on at least two planes designated by the color, the height of the reference point to the layer is higher It is characterized in that a graphic on a plane is preferentially displayed on the layer.

Further, according to a fourth method of hidden line processing of a two-dimensional drawing of the present invention, when a plurality of figures are displayed on a layer to create a two-dimensional drawing, the layer has an arbitrary inclination with respect to the layer and Define a plurality of planes having a reference point at a position at an arbitrary height above without limiting the area, and associate different colors for each plane with each plane and at the same time at any position on each plane. At least one figure is drawn in a corresponding color, and the figure on at least two planes specified by the color among the plurality of planes is set to the height of the reference point of the plane with respect to the layer and the inclination of the plane. And a figure having a higher height with respect to the layer, which is obtained based on the position of the figure on the plane, is preferentially displayed on the layer.

In the third and fourth methods, the shape data of each figure drawn on the plane may be stored with the data of the figure name added as an attribute.

In the third and fourth methods, when a plurality of figures are drawn on the same plane, the figures are distinguished from each other by using the data of the name added to each figure. By giving one or more types of master-slave relationship between these multiple figures, and registering the master-slave relationship,
The plurality of graphics may be displayed on the layer based on the registered master-slave relationship.

In this specification, "above the layer" refers to a position separated from the layer in the direction perpendicular to the layer, with the layer horizontally placed for the sake of convenience, and "to the layer". The “height” represents the distance in the direction perpendicular to the layer with respect to the layer in a state where the layer is placed horizontally for convenience.

[0016]

According to the first method described above, since each sheet extends in parallel with the layer, the figure (part) on each sheet is at the same height as that sheet. By only defining the height of the reference point on the sheet, hidden line processing can be performed simultaneously for each sheet when inserting or deleting multiple figures or replacing heights, greatly reducing the time required for instructions and input. In addition, the hidden line processing can be performed by a simple processing procedure.

According to the second method, the height of the figure with respect to the layer is obtained based on the height of the reference point of the sheet with respect to the layer, the inclination of the sheet and the position of the figure on the sheet, and the height thereof is obtained. The graphic on each sheet is displayed on the layer by giving priority to the graphic with the higher value, so that it is possible to greatly save the trouble of instructing and inputting similarly to the first method, and the graphic inclined to the layer. Also, hidden line processing can be performed on the.

Further, as in the third and fourth methods, instead of the plurality of sheets in the first and second methods, a plurality of planes whose areas are not particularly limited are set, and those planes are set. Corresponding different colors to each plane,
Similar to the sheet, the planes are used to draw a figure, and the figure to be drawn on the plane is given a color corresponding to the plane, and among the plurality of planes, at least two planes designated by the color are used. If the figure is displayed on the layer, it is possible to handle hidden figures, movements, rotations, etc. of a plurality of figures in color units, so that the figure should be handled even when the number of planes increases. It can be done easily.

If the shape data of each figure drawn on the sheet or on the plane is stored with the data of the figure name added as an attribute, the figure can be specified by the name. With, you can easily copy the same figure on the same sheet or another sheet, and
It is possible to easily rotate, turn on, and turn off for each figure.

Further, when a plurality of figures are drawn on the same sheet or on the same plane, the figures are distinguished by using the data of the name added to each figure, so that the figures are separated from each other. If one or a plurality of types of master-slave relationship is given to the, and the master-slave relationship is registered in advance, and the plurality of figures are displayed on the layer based on the registered master-slave relationship, on the same sheet, You can also perform hidden line processing between multiple figures drawn on the same plane, and if you register multiple types of master-slave relationships when registering them, the master-slave relationship will be By selecting and specifying a desired relationship, the state of hidden line processing can be changed and a desired type of drawing can be displayed on a layer.

[0021]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory diagram illustrating a plurality of sheets defined in an embodiment of a hidden line processing method of a two-dimensional drawing of the present invention and a two-dimensional drawing in which a graphic is displayed on a layer by the method of the embodiment. , The method of this example is
A central processing unit that performs arithmetic processing regarding figures and the like, internal storage devices such as ROM and RAM that record information regarding figures and the like, external recording devices such as hard disk drive devices, and CRTs that display information regarding figures and the like on the screen. Screen display device, an input device such as a keyboard, mouse, digitizer, etc. that the user operates to input information related to figures and commands, and a plotter or printer that outputs information related to figures such as drawing on the paper It shall be implemented in a conventional CAD system with an output device.

FIG. 2 is a flow chart showing a processing procedure in the method of the above-mentioned embodiment. Here, in step 1, a user defines a layer which is a virtual plane for displaying a figure by inputting a drawing number, Next step 2
And the sheet number of the sheet that is the virtual plane for drawing the figure
The user sets the (No.) and the sheet area A by inputting. In this embodiment, when the user does not input anything, the CAD system automatically sets the sheet number to 1 first, and thereafter sequentially increases the number and sets the sheet area A over the entire layer. Set as an area.

In the next step 3, the user inputs the name of the figure to be drawn on the sheet having the number and area set as described above, for example, the part name or the part number, and then uses the mouse or the like. A shape representing the shape of the part is drawn on the sheet to define the shape of the part. Thus, in this case, the CAD system attributes the data of the name of the part, the sheet number of the sheet on which the graphic is drawn, and the position of the graphic on the sheet to the graphic data of the shape defined above. And the data is registered in the memory. When existing external graphic data such as an electronic catalog is used, the graphic data may be called by previously naming the graphic data with component names.

Then, in the following step 4, the CAD system inquires of the user whether or not to further define the shape on the sheet, and when the user inputs that the shape is further defined on the same sheet, the process returns to step 3 above. When the user inputs the information when the definition of the shape on the sheet is completed, the process proceeds to the next step 5, in which the user sets the reference point P at a predetermined position such as the lower left corner of the sheet. , A position (x, y) on the X, Y coordinate system of the layer, and a Z value indicating the height of the reference point P in the vertical direction (Z axis direction) with respect to the layer,
A normal vector V (x _D, y of the sheet at the reference point P
_D, z _D ), and the CAD system registers the data in the memory together with the sheet number and the sheet area data set as above. If the user does not enter anything, the CAD system automatically sets P =
Initialize (0, 0), Z value = 0, V = (0, 0, 1).

In step 6 thereafter, the CAD system inquires of the user whether or not to define the shape on the new sheet, and if the user inputs that the shape is to be defined on the new sheet, the procedure returns to step 2 above. When the shape is defined on two or more sheets and the user inputs to finish the definition of the shape thereafter, the next step 7
Go to. Here, since the data of the figure representing the shape of the part is registered by adding the name of the part, when returning to the step 4 or step 6 and performing the step 3, the figure of the shape already defined is registered. To use it again, just enter the name and placement of the part with that shape,
The CAD system reads the data of the figure of the shape from the memory and draws it in the input arrangement. Therefore, according to this embodiment, the graphic of the already defined shape can be easily copied on the same sheet or another sheet, and
It can be easily rotated and turned on and off.

When the definition of the shape of each part is completed as described above, the CAD system executes hidden line processing in step 7 here. This hidden line processing defines all the sheets as parallel to the layers. And the case where one or more sheets are defined by inclining with respect to the layer is different.
That is, when all the sheets are defined as being parallel to the layer, the graphics of the parts on each sheet are at the same height as the reference point P of the sheet because each sheet extends parallel to the layer. In the conventional method described in Japanese Patent Laid-Open No. 3-95691 described above, the priorities of the respective figures are compared and the figures are overlaid in order from the lowest priority. Among the plurality of sheets, the figures on the remaining sheet except the sheet input by the user unless used for drawing creation are respectively the position of the reference point P of the sheet on the layer and the figure on the sheet. Of the remaining sheets, the heights (Z values) of the reference points P of the remaining sheets are compared with each other, and the height of the figures overlapping each other on the layer is projected as a result of the projection. The lower one If the entire figure on the sheet with the lower height overlaps the figure on the sheet with the higher height, cuts or cuts the overlapping part of the figure on the sheet with the figure on the lower sheet. Delete the whole figure or make it a broken line.

Therefore, for example, as shown in FIG. 1, sheet number 1, sheet area A = (0, 0), (1000, 500), reference point P = (0, 0), normal vector V = ( 0, 0, 1), Z value = 0
Sheet S ₁ , sheet number 2, sheet area A = (0, 50
0), (1000, 1000), reference point P = (0, 500), normal vector V = (0, 0, 1), Z value = −10 sheet S ₂ , sheet number 3, sheet area A = (500, 250), (1500, 750), reference point P = (500, 250), normal vector V = (0, 0, 1), Z = 15
0 sheet S ₃ and ₃ sheets S ₁ , S ₂ and S ₃ are defined,
On those sheets, three parts with part numbers D ₁ , D ₂ and D ₃
If the D _1, D _2, and D ₃ of the shape graphic representing a defined and drawn respectively, on the layer of FIG. 1 L, part D ₃ on the sheet S ₃ is the highest priority, then the sheet Parts on S ₁ and S ₂ D ₁ and D ₂
Is prioritized to represent the shapes of those parts D ₁ , D ₂ , D ₃ .
The right part of the parts D ₁ and D ₂ overlaps with the highest priority part D ₃ , so that it is broken, for example.

On the other hand, when one or more sheets are defined by inclining with respect to the layers, the figures on two sheets having the same height of the reference point P but different inclinations have the same arrangement with respect to the reference point P. However, since the height with respect to the layer is different, and the two figures having different arrangements with respect to the reference point P on the inclined sheet also have different heights with respect to the layer, the figure on the inclined sheet is Is
The heights of the constituent points are geometrically obtained from the positions of the constituent points of the figure with respect to the reference point P of the sheet and the inclination of the sheet.

Of the plurality of sheets defined above, the figures on the remaining sheets except the sheet input by the user unless they are used for drawing creation are projected on the respective layers, and the remaining sheets are drawn. For sheets parallel to the layer, the height (Z value) of the reference point P is compared for each sheet, but for the sheet tilted with respect to the layer, instead of the reference point P of the sheet, the height of the above-mentioned constituent points is used. As a whole, the heights of all the constituent points of the figure are compared with the reference point P of another sheet parallel to the layer and the entire height of the constituent points of the figure on the other sheet inclined to the layer. , If the height is higher than the reference point P of another sheet or all the constituent points of the figure on the other sheet, the figure has priority over the figure on the other sheet. Prioritize the shapes on the sheet As a result, of the figures that overlap each other on the layer as a result of the above projection, the overlapping part of the figure with the lower height is cut off or broken, and the figure with the lower height as a whole has a higher height. When it overlaps with the figure, the whole figure of the lower one is deleted or broken.

Therefore, for example, as shown in FIG. 3, when the sheet S ₄ is viewed from the direction of arrow C, the sheet S ₄ is defined in front of the layer L (upward as a Z value) by tilting the layer S and the layer S ₄ is defined. A sheet S ₅ is defined between L and the sheet S _{4 in} parallel with the layer L, and parts are placed on the sheets S ₄ and S _5.
When the figures representing the shapes of D ₄ and D ₅ are drawn and defined, since the constituent points P _{1 to} P ₆ of the figure of the part D ₄ are all higher in Z value than the reference point P of the sheet S ₅ . , The part D ₄ shape is a sheet
Than graphic component D ₅ on S ₅ is given priority, thus the layer L
In the upper part of the figure representing the shape of the part D ₅ , the part overlapping with the figure representing the shape of the part D ₄ having a higher height is broken, for example, and the shape of those parts D ₄ and D ₅ is shown. A graphic obtained by projecting in the direction of arrow C is displayed. If the projection direction of the figure is different, the inclination of the sheet may be changed or the layer itself may be changed to define the figure again.

After the hidden line processing is performed in the step 7, the CAD system displays the layer in which the graphics of the plurality of parts are displayed by the hidden line processing in the step 8 in the CRT.
Etc. are actually displayed on the screen of the screen display device or printed out by a plotter or the like.

Therefore, according to the method of the above-described embodiment, when a plurality of sheets are all defined in parallel with the layers, the heights of the reference points of the sheets are compared to obtain a plurality of sheets on each sheet. Since the heights of parts are compared at once, basically when defining a sheet, simply define the height of the reference point of the sheet, and you can insert or delete multiple figures or replace heights. The hidden line processing when performing the above can be performed simultaneously on a sheet-by-sheet basis, and the trouble of instruction and input can be greatly saved.

Further, according to the method of the above embodiment, when one or more of the plurality of sheets are defined by being inclined with respect to the layer, the height of the reference point of the sheet with respect to the layer and the inclination of the sheet. The height of the figure with respect to the layer is calculated based on the figure and the position of the figure on the sheet, and the figure with the higher height is given priority and the figure on each sheet is displayed on the layer. As in the case where all the sheets are defined in parallel with the layers, the trouble of instruction and input can be greatly reduced, and the hidden line processing can be performed on the figure inclined to the layer.

By the way, with the above-described embodiment as it is, when a plurality of figures are drawn on the same sheet and the figures overlap each other, different height information cannot be given to the figures. Therefore, although there is some inconvenience in that the hidden line processing cannot be performed, the inconvenience can be solved by the modified examples described below. That is, in this modification, the figures are distinguished from each other by using the data of the part names added to the respective figures in step 3 of the above-mentioned embodiment. For example, between step 4 and step 5 of the above-mentioned embodiment, The step of giving one or more kinds of master-slave relationship between the plurality of figures by inputting, the master-slave relationship is registered in the master-slave relationship file set for each sheet, and in step 7 of the above embodiment, When the plurality of graphics drawn on the same sheet are displayed on the layer L, the master graphics are displayed with priority over the slave graphics based on the registered master-slave relationship for the sheet.

FIG. 4 shows an example in which the above modification is applied to display a drawing of a tool head of a machine tool. In the example shown in FIG. 4, the master-slave relationship file set for a certain sheet is used. As shown in Table 1 below, a master-slave relationship using component names is registered. The parts in Table 1 have a relationship in which the part on the front side (left) of the arrow is the main part, and the part on the tip side (right) of the arrow is the subordinate. The contents shown in Table 1 exemplify a part of the master-slave relationship between the parts shown in FIG.

[0036]

[Table 1]

By using the master-slave relationship in the file as described above, a graphic representing a plurality of components as described above drawn on the same sheet is given priority over a graphic having a primary component name over a graphic having a secondary component name. If it is displayed on the layer L as shown in FIG.
As shown in FIG. 2, for example, a tooling schematic view (side view) of a tool head of a machine tool can be drawn.

A plurality of types of the master-slave relationship may be registered in the master-slave relationship file for one sheet. For example, in Table 1 in the master-slave relationship file for the sheet used to display the drawing of FIG. In addition to the master-slave relationship shown, the master-slave relationship as shown in Table 2 below is registered, and when the figures representing a plurality of parts drawn on the sheet are displayed on the layer L, the one shown in Table 2 If you select and use the master-slave relationship of
As shown in FIG. 5, with the same plurality of parts as in FIG. 4,
For example, a tooling detailed view (cross-sectional view) of a tool head of a machine tool can be drawn. The contents shown in Table 2 also exemplify a part of the master-slave relationship between the parts shown in FIG.

[0039]

[Table 2]

Further, with the above-described embodiment as it is, since the sheet number and the sheet area A are set for each sheet, the sheet management becomes difficult when the number of sheets increases, which is somewhat inconvenient. However, according to another embodiment of the present invention described below, such inconvenience can be solved. That is, in this embodiment, in place of the plurality of sheets _{S 1, S 2, S 3} ··· used in the previous embodiment, as shown in FIG. 6, a plurality of planes PL ₁ is not defined region, PL ₂ ...
Are set to correspond to different colors for each plane instead of numbers, such as yellow on the plane PL ₁ and red on the plane PL ₂ in the figure. At the position, for example, a reference point P _Y is provided on the plane PL ₁ and a reference point P _R is provided on the plane PL ₂ , and the planes are arranged in the direction perpendicular to the color and the layer L (Z-axis direction). ) Is used to define the height of the reference point and a normal vector to the plane at the reference point, and these planes are used for drawing a graphic as in the above sheet. , Add colors corresponding to the planes to the figures drawn on those planes.

In this case, at the time of displaying a figure on the layer L, at least two planes among the plurality of planes are referred to by referring to, for example, the color of the figure drawn on the plane. The shapes on those planes, for example, the figure D _Y on the plane PL ₁ corresponding to yellow and the figure D on the plane PL ₂ corresponding to red, as shown in FIG.
_R and _R are displayed on the layer L by performing a hidden line process based on the positions of the reference points P _Y and P _{R with} respect to the origin of L and the direction of the normal vector. In the example shown in FIG. 6, the Z value of the reference point P _Y of the plane PL ₁ corresponding to yellow is set to 0, while the Z value of the reference point P _R of the plane PL ₂ corresponding to red is set to −50. ,
Since the normal vector is set to (0, 0, 1) on both planes, the portion of the graphic D _R overlapping the graphic D _Y is displayed in broken lines.

FIG. 7 is a flow chart showing the processing procedure in the hidden line processing method of the above embodiment. The method of this embodiment is also carried out in the above-mentioned ordinary CAD system. The user defines the layer that is the virtual plane to be displayed by inputting the drawing number, etc., and then, in step 22, sets the plane that is also the virtual plane that also draws the figure, without limiting the area, and The color corresponding to the plane is set by the user specifying the display color of the figure to be drawn by input. It should be noted that the planes corresponding to the colors can be set on a part name basis or a line segment basis, and can be set on a layer basis when there are multiple layers.

At the next step 23, the user inputs the name of the figure to be drawn on the plane in which the corresponding color is set as described above, for example, the part name or the part number, and then the mouse is used to A shape representing the shape of the part is drawn on a plane to define the shape of the part. As a result, in this case, the CAD system adds the name of the part, the color corresponding to the plane on which the graphic is drawn, that is, the display color of the graphic, to the graphic data of the shape defined above, and the color on the plane. Data such as the position of the figure is added as an attribute, and the data is registered in the memory. Even in this embodiment, when the already existing external graphic data such as an electronic catalog is used, the graphic data may be called by previously naming the graphic data with component names. good.

Then, in the following step 24, the CAD system inquires of the user whether or not to further define the shape on the plane, and if the user inputs that the shape is further defined on the same plane, the process returns to step 23. , When the user finishes defining the shape on the plane and the user inputs it, the process proceeds to the next step 25. At this step 25, the user places the point P _Y at an arbitrary position on the plane, for example, as shown in FIG. A reference point such as the point P _R is set to define the position of the reference point on the plane, and the Z value of the reference point and the normal vector V of the plane at the reference point are set.
_{(X D, y D, z} D) defines a, CAD system these data, are registered in the color attribute file CF in the memory along with the set color. Hereby,
It is possible to specify the position of the figure drawn on the plane as the position of the plane with respect to the reference point.

In the subsequent step 26, the CAD system inquires of the user as to whether or not to define the master-slave relationship for each part name, and a plurality of part shapes overlapping each other on the same plane are defined, so that a modification of the previous embodiment. If you also want to define a master-slave relationship between them, as in
The user defines the master-slave relationship of the plurality of parts by using the part name, and the CAD system registers the data of the master-slave relationship in the master-slave relationship file MF in the memory. If it is unnecessary to register the master-slave relationship in step 26 above and after registering the master-slave relationship data in step 27 above, in step 28, whether to define the shape on a new plane corresponding to the new display color is determined. If the CAD system inquires of the user and the user inputs that the shape is to be defined on a new plane, the procedure returns to the above step 22, but if the shape is already defined on two or more planes and the subsequent definition of the shape is completed. If the user inputs, go to the next step 29.

In this embodiment as well, since the data of the figure representing the shape of the part is registered with the name of the part, it is already defined when the process returns from step 24 or step 28 to step 23. When the graphic of the shape is used again, the CAD system reads the data of the graphic of the shape from the memory by simply inputting the name and the layout of the part having the shape, and draws the graphic in the input layout. Therefore, also in this embodiment, the graphic having the already defined shape can be easily copied on the same plane or another plane, and can be easily rotated, turned on and off.

When the definition of the shape of each part is completed as described above, the CAD system executes hidden line processing in step 29 here. This hidden line processing is the same as in the previous embodiment. Differs when all are defined as being parallel to the layer, and when one or more planes are defined by inclining with respect to the layer. That is, when all the planes are defined as being parallel to the layer, since each plane extends parallel to the layer, the figure of the part on each plane is at the same height as the reference point of that plane. Of the multiple defined planes, the figures on the planes remaining except for the planes entered by the user if they are not used for drawing creation are used as the reference points of the planes on the layers registered in the color attribute file CF. Based on the position and the arrangement of the figure with respect to the reference point on that plane, it is projected on the layer and displayed in colors corresponding to those planes, and the height of the reference point (Z Value) is compared, and among the figures that overlap each other on the layer as a result of the above projection, the overlapping part of the figure on the plane with the lower height is cut off or broken, and the plane on the plane with the lower height is cut off. The entire shape of is If overlapping the shapes on have how plane, delete or broken lines the entire figure of the plane of the lower.

Therefore, for example, as in the example of FIG. 6 described above, the Z value of the reference point P _Y is set to 0, the direction of the normal vector is set to (0, 0, 1), and the reference point P _Y is extended in parallel with the layer. Figure D _Y on the plane PL ₁ corresponding to yellow and the reference point P _R
With a Z value of −50 and a normal vector direction of (0,0,1), and a figure D _R on the plane PL ₂ corresponding to the red color extending in parallel with the layer with respect to the origin of L. If the positions of the reference points P _Y and P _R are shifted from each other and projected on the layer L as shown in the lower part of the figure, the Z values are different due to the difference in the Z values of the reference points P _Y and P _R. Small red figure D _R on the lower side, yellow figure D _{Y on the} upper side with a large Z value
The portion overlapping with is displayed as a broken line as described above.

Further, as shown in FIG. 8, for example, the reference point P
The Z value of _Y is set to 0, the direction of the normal vector is set to (0, 0, 1), and the figure D _Y on the plane corresponding to yellow that extends parallel to the layer is designated, for example, its part name. As a result, the Z value of the reference point P _R is set to −50, and the direction of the normal vector is set to (0, 0, 1), and the relative to the reference point on the plane corresponding to the red color that extends in parallel with the layer. The figure D _R is copied without changing the position, and the figures D _Y and D _R are shifted from each other with respect to the origin of L so that the positions of their reference points P _Y and P _R are displaced from each other as shown in the lower part of the figure. If it is projected on L, as shown in FIG. 8, two identical parts can be displayed on the layer L by shifting the positions and performing hidden line processing. It can be displayed easily.

On the other hand, when one or more planes are defined by inclining with respect to the layer, figures on two sheets having the same height of the reference points but different inclinations are layered even if they are arranged at the same reference point. The height for
Further, since two figures having different arrangements with respect to the reference point on the inclined plane also have different heights with respect to the layers, the figure on the inclined plane is the same as that of the previous embodiment. The heights of the constituent points are geometrically determined from the positions of the constituent points of the figure with respect to the reference point and the inclination of the plane defined by the normal vector.

Then, among the plurality of planes defined above, the figures on the planes other than the planes input by the user if they are not used for creating the drawing are used as the planes on the layers registered in the color attribute file CF. Project on a layer based on the position of the reference point and the placement of the figure relative to the reference point on that plane, and display it in the colors corresponding to those planes,
Regarding the remaining planes, the heights (Z values) of the reference points are compared for each plane for the plane parallel to the layer,
As for the plane inclined with respect to the layer, as in the case of the previous embodiment, instead of the reference point of the plane, the heights of the above-mentioned constituent points as a whole are used as reference points of other planes parallel to the layer, and Compared with the total height of the constituent points of the figure on the other plane that is tilted, the heights of all the constituent points of the figure are the reference points of the other plane and all the constituent points of the figure on the other plane. If it is higher than the height of, the shape is prioritized over the shape on other planes, and if it is lower, the shape on other planes is prioritized. Of the lower figure, the overlapping part of the lower figure is cut off or broken into lines, and if the entire lower figure overlaps the higher figure, the lower figure Delete the whole or make it a broken line.

Therefore, for example, as shown in FIG. 9, a plane corresponding to red by tilting the layer L to the front (upper Z value) of the layer L when viewed from the direction of arrow C.
PL ₂ is defined, and a plane PL ₁ corresponding to yellow is defined between the layer L and the plane PL _{2 in} parallel with the layer L,
Figures D _Y and D representing the shape of parts on the planes PL ₁ and PL ₂
When defined by drawing _R, respectively, since the higher Z value than the reference point P _R of all constituent points of the figure D _R plane PL _1, figure D _R Shapes D of generally plane PL _{1 Y} also overrides, on thus-layer L, as shown on the left side of FIG. 9, of the figure D _Y, high overlap in the graphic D _R of it than the height for example is a broken line of their Figure D _R ,
A figure obtained by projecting D _Y in the direction of arrow C is displayed.

Further, since a plurality of parts shapes that overlap each other on the same plane are defined, the master-slave relationship between them is defined as in the case of the modification of the previous embodiment, and the data of the master-slave relationship is stored in the memory. When registered in the relationship file MF, also in step 29 of the above-mentioned embodiment, based on the master-slave relationship selected by the user in the data registered in the master-slave relationship file MF, a plurality of component shapes that overlap each other on the same plane Hidden lines are processed. If the user does not want the hidden line processing, it is possible to display all the shapes of a plurality of parts that overlap each other on the same plane as they are.

After performing the hidden line processing in step 29, in step 30, the CAD system performs CRT processing on the layer in which the graphics of the plurality of parts are hidden line processed and displayed.
Etc. are actually displayed on the screen of the screen display device or printed out by a plotter or the like.

Although the present invention has been described above based on the illustrated example, the present invention is not limited to the above example. For example, in the above embodiment, the sheet or the plane may be tilted with respect to the layer to be defined. However, it is also possible to define only a plurality of sheets or planes only parallel to the layers (the input of the direction vector is omitted), if necessary, such as the processing capacity of the apparatus to be implemented. It can be simple.

The method of the present invention can be carried out by an apparatus other than the CAD system as long as it is an apparatus for performing graphic processing using a computer.

[0057]

As described above, according to the first method of the hidden line processing method for a two-dimensional drawing of the present invention, basically, when a sheet is defined, only the height of the reference point of the sheet is defined. Hidden line processing can be performed at the same time for each sheet when inserting or deleting figures, changing heights, etc.
It is possible to greatly save the trouble of instructing and inputting, and the hidden line processing can be performed by a simple processing procedure.

Further, according to the second method of the hidden line processing method for a two-dimensional drawing of the present invention, it is possible to greatly save the trouble of instructing and inputting similarly to the above-mentioned first method, and to incline the layer. Hidden line processing can be performed on the drawn figure.

Further, as in the third and fourth methods of the hidden line processing method of the two-dimensional drawing of the present invention, the region is particularly limited in place of the plurality of sheets in the first and second methods. Do not set multiple planes, assign different colors to each plane, and use those planes for drawing figures in the same way as the above-mentioned sheet and the color corresponding to that plane for the figures drawn there. Given, among the plurality of planes, to display the figure on at least two planes specified by the color on the layer, a plurality of figures, hidden line processing or movement in color units,
Since handling such as rotation is possible, it is possible to easily handle graphics even when the number of planes increases.

If the shape data of each figure drawn on the sheet or the plane is saved with the data of the figure name added as an attribute, the figure can be specified by the name. With, you can easily copy the same figure on the same sheet or another sheet, and
It is possible to easily rotate, turn on, and turn off for each figure.

Further, when a plurality of figures are drawn on the same sheet or the same plane, the figures are distinguished by using the data of the name added to each figure, so that the figures are separated from each other. If one or a plurality of types of master-slave relationship is given to the, and the master-slave relationship is registered in advance, and the plurality of figures are displayed on the layer based on the registered master-slave relationship, on the same sheet, You can also perform hidden line processing between multiple figures drawn on the same plane, and if you register multiple types of master-slave relationships when registering them, the master-slave relationship will be By selecting and specifying a desired relationship, the state of hidden line processing can be changed and a desired type of drawing can be displayed on a layer.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a plurality of sheets defined in an embodiment of a hidden line processing method of a two-dimensional drawing of the present invention and a two-dimensional drawing in which a graphic is displayed on a layer by the method of the embodiment. is there.

FIG. 2 is a flowchart showing a processing procedure in the method of the above embodiment.

FIG. 3 is an explanatory diagram showing another example of a plurality of sheets defined by the method of the above embodiment and a two-dimensional drawing in which graphics are displayed on layers by the method in this embodiment.

FIG. 4 is an explanatory diagram showing an example of a two-dimensional drawing in which a plurality of figures drawn on the same sheet by the method of the above embodiment is displayed on a layer.

FIG. 5 is an explanatory diagram showing another example of a two-dimensional drawing in which a plurality of figures drawn on the same sheet by the method of the above-described embodiment are displayed on a layer.

FIG. 6 is an explanatory diagram showing an example of a plurality of planes defined in another embodiment of a hidden line processing method of a two-dimensional drawing of the present invention and a two-dimensional drawing in which a graphic is displayed on a layer by the method of the embodiment. Is.

FIG. 7 is a flowchart showing a processing procedure in a method of the other embodiment.

FIG. 8 is an explanatory diagram showing another example of a two-dimensional drawing in which a graphic is displayed on a layer by the method of the other embodiment.

FIG. 9 is an explanatory diagram showing still another example of a plurality of planes defined by the method of the other embodiment and a two-dimensional drawing in which graphics are displayed on layers by the method in this embodiment.

FIG. 10 is an explanatory diagram showing an example of a conventional hidden line processing method.

FIG. 11 is an explanatory diagram showing another example of a conventional hidden line processing method.

FIG. 12 is an explanatory diagram showing still another example of a conventional hidden line processing method.

[Explanation of symbols]

L layer S ₁ , S ₂ , S ₃ sheet D ₁ , D ₂ , D ₃ parts P Reference point

Claims (8)

[Claims] 1. When a plurality of figures are displayed on a layer to create a two-dimensional drawing, a sheet that extends in parallel with the layer and has a reference point at an arbitrary height position above the layer is used. A plurality of sheets are defined, and at least one figure is drawn at an arbitrary position on each of the sheets, and the figure on at least two sheets of the plurality of sheets is defined by the height of the reference point with respect to the layer. A method of processing hidden lines in a two-dimensional drawing, characterized in that the graphic on the sheet having a higher height is preferentially displayed on the layer. 2. A sheet having an arbitrary inclination with respect to the layer and a reference point at an arbitrary height position above the layer when a plurality of figures are displayed on the layer to create a two-dimensional drawing. Defining a plurality of sheets, draw at least one figure at an arbitrary position on each of the sheets, the figure on at least two sheets of the plurality of sheets, the sheet reference to the layer 2. A graphic having a higher height with respect to the layer obtained based on the height of the point, the inclination of the sheet, and the position of the graphic on the sheet is preferentially displayed on the layer. Hidden line processing method for three-dimensional drawings. 3. The two-dimensional according to claim 1, wherein the shape data of each figure drawn on the sheet is stored with the data of the figure name added as an attribute. Hidden line processing method for drawings. 4. When a plurality of figures are drawn on the same sheet, the figures are distinguished from each other by using the data of the name added to each figure, so that one or The plurality of types of master-slave relationships are given, the master-slave relationship is registered in advance, and the plurality of figures are displayed on the layer based on the registered master-slave relationship. Hidden line processing method for three-dimensional drawings. 5. When a plurality of figures are displayed on a layer to create a two-dimensional drawing, a plane extending parallel to the layer and having a reference point at an arbitrary height position above the layer is formed. A plurality of areas are defined without limitation, each plane is associated with a different color for each plane, and at least one figure is drawn at an arbitrary position on each plane with a color corresponding to the plane, Among the planes, the figures on at least two planes designated by the color are displayed on the layer by giving priority to the figure on the plane having a higher height of the reference point with respect to the layer. A method for processing hidden lines in a two-dimensional drawing. 6. A plane having an arbitrary inclination with respect to the layer and having a reference point at an arbitrary height position above the layer when a plurality of figures are displayed on the layer to create a two-dimensional drawing. Defining a plurality of areas without limiting the area, each plane is associated with a different color for each plane, and at least one figure is drawn at an arbitrary position on each plane with a color corresponding to the plane, Of the planes on at least two planes designated by the color are obtained based on the height of the reference point of the plane with respect to the layer, the inclination of the plane, and the position of the figure on the plane. A hidden line processing method for a two-dimensional drawing, characterized in that a graphic having a higher height with respect to the layer is preferentially displayed on the layer. 7. The two-dimensional according to claim 5, wherein the shape data of each figure drawn on the plane is stored with the data of the figure name added as an attribute. Hidden line processing method for drawings. 8. When a plurality of figures are drawn on the same plane, the figures are distinguished from each other by using the data of the name added to each of the figures, so that one or The plurality of types of master-slave relationships are given, the master-slave relationship is registered, and the plurality of figures are displayed on the layer based on the registered master-slave relationship. Hidden line processing method for three-dimensional drawings.