JPS62160575A - Object image synthesizing device - Google Patents

Abstract

PURPOSE:To reduce a process accompanied by the change of an area shape by comparing a load on a luminance calculation part with that on an adjacent luminance calculation part, changing a boundary plane based on the result of comparison, nd changing the range of an area in charge. CONSTITUTION:An initial ray of light generation part 1 generates bits of information of plural rays of light passing each picture element of an image synthesized from a visual point set in advance, and takes charge of one area of plural areas generated by dividing a space where an object is defined at a luminance calculation part 3, and performs tolerance decision process between the ray of light passing the area and the object included in the area in charge, then the luminance of each picture element being calculated. The luminance calculation part 3 compares the load communication with the luminance calculation part 3 which takes charge of an adjacent area, and based on a compared result, it moves the boundary plane between the area in charge and the adjacent area, and changes the range of the area in charge stored at an area information storage means so as to change the shape of the area in charge.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an object image synthesis device that synthesizes images for displaying objects.

(Prior Art) As a method of synthesizing digital images for displaying objects, there is a method called a ray search method.

In this method, the path of the line from the light source to the viewpoint is traced in the opposite direction to perform intersection determination processing between the light ray and the object, and the brightness of each pixel making up the image is calculated based on the result. An example of this ray search method is published by Information Processing Society of Japan, Volume 25, No. 6, Hiroshi Deguchi.

Written by Hitoshi Nishimura, Hiroshi Yoshimura, Akira Kawata, Isao Shiro, and Hiroshi Omura.

Paper “Computer Graphics System LINKS
1).

In order to generate images quickly using such a ray search method, the space in which the object is defined is divided into multiple regions, and each region is assigned to one computer.
A method has been proposed in which each computer processes the light rays passing through its assigned area. Details of this method can be found in Computer Graphics.
Graphics), Volume 18, No. 3, Mark Dippe, John Swensen, article “An
Adaptive Subdivision Algorithm and Parallel Architecture for Realistic Image Synthesis
5ubdivision Algorithm an
dParallel Architecture for
r Realistic image Syntheai
s) described in J.

In the above method, the space 1'i is first divided into a plurality of rectangular parallelepiped regions, and each region is assigned to one computer. Then each computer has
The data of the object included in the assigned (α-cuboid-shaped area) is stored. Then, each computer performs an intersection determination process between the object and the light ray passing through the assigned area.

Through this intersection determination processing, when the object and the light ray intersect, reflection and transmission processing on the object surface is performed. Information about rays that do not intersect objects within that region is transferred to computers assigned to adjacent regions.

When performing such processing, there is a possibility that there will be slight variations in the amount of processing performed by each computer. In other words, a computer that is assigned an area that contains many objects has a very large amount of processing to do, while a computer that is assigned an area that does not contain any objects may not be able to process much at all. be.

In order to reduce such variations in load between computers, a method has been proposed in which the vertices of a region divided into rectangular parallelepipeds are arbitrarily moved to change the volume and shape of the region. That is, by moving the vertices, the computer processing (rt) decreases by dividing the area into a region whose volume has decreased. Then, the processing for that amount is shared with the computer that is reassigned to the area whose volume has increased due to the movement of the vertex. In this way, the load is redistributed among the computers.

(Problems to be Solved by the Invention) In such a conventional load redistribution method, the shape of the region changes in various ways in order to redistribute the top position of the region in fl 匍11. Put it away. That is, since the deformation is due to the movement of vertices, the shape of the region is kept as a hexahedron, but the orientation and shape of each boundary surface of the region can be arbitrary. This causes the following problems.

First, when transmitting light beam information from a divided region to an adjacent region, the region to be transferred is determined by determining the intersection between the boundary surface of the region and the light beam.

However, since the orientation and shape of each boundary surface of the region are arbitrary, the processing amount of this intersection determination process becomes extremely large. Therefore, there is a problem that the overall processing time becomes slow.

Second, when the shape of a region is changed, information about objects included in the region must also be changed.

That is, in the case of a region whose volume has decreased, there is a possibility that some objects that were included in the region before the change are no longer included in the region after the change. In addition, in the case of a region whose volume has increased, there is a possibility that an own object is included in the region.

Even when such object information is changed, since the shapes of the regions vary, there is a problem in that the processing amount and processing time required for processing to determine objects included in the region become extremely large.

As described above, the conventional method of redistributing the load by moving the vertices of the area has the problem that the redistribution requires a very large amount of processing, and the effect of the redistribution cannot be sufficiently obtained.

The present invention simplifies the process of changing the area shape for load redistribution, thereby reducing the processing involved in changing the area shape and sufficiently increasing the effect of redistribution. The purpose of the present invention is to provide an image synthesis device.

(Means for Solving the Problems) The object image synthesis device of the present invention includes an initial ray generation section that generates information on a plurality of rays that pass through each pixel from a viewpoint, and an object information setting section that sets object information. , in charge of one region out of a plurality of regions generated by dividing the space in which the object is defined, and perform intersection determination processing between a ray passing through this region and an object included in the assigned region; It is composed of a plurality of brightness calculating sections that calculate the brightness of the above-mentioned pixels, and an image storage section that stores the brightness calculated by the brightness calculating section as an image. Area information storage means for storing the range of the area in charge of the brightness calculation section among a plurality of areas generated by dividing the defined space along a plane perpendicular to the coordinate axes; and a load determination device for determining the load of the brightness calculation section. means, mutual communication means for mutually communicating between the brightness calculation unit and an adjacent brightness calculation unit that is in charge of an area adjacent to the area in charge in a direction parallel to a specific coordinate axis, and a brightness obtained through the mutual communication means. A load comparison means for comparing the load of the adjacent brightness calculation unit and the load of the brightness calculation unit, and based on the comparison result of the load comparison means, the boundary surface between the responsible area and the adjacent area is parallel to the specific coordinate axis. and an area changing means for changing the range of the area in its duty stored in the area information storage means in order to change the shape of the area in its duty by moving in a certain direction.

(Function) The load redistribution method in the present invention will be described. Each brightness calculation unit is assigned one area out of a plurality of areas generated by dividing the object definition space along a plane perpendicular to the coordinate axes as the area in charge of that brightness calculation unit. The range of this assigned item area is stored in area information storage means provided in the brightness calculation section.

Here, among the areas adjacent to the area in charge of this brightness calculation unit, a brightness calculation unit that is in charge of an area in a direction parallel to a specific coordinate axis is called an adjacent brightness calculation unit.

The load of each brightness calculation unit is determined by the load determining means and transferred to the adjacent brightness calculation unit via the mutual communication means. The load comparison means compares the load determined by the load determination means with the load of the adjacent brightness calculation unit obtained via the mutual communication means.

Based on this comparison result, the area changing means determines the amount and direction of movement of the boundary plane perpendicular to the specific coordinate axis of the area in its charge so that the load on each brightness calculation unit is smoothed. Then, the range of the assigned area stored in the area update storage means is changed, and the assigned area is changed.

In this way, by changing the area in charge based on the load comparison result, the load is redistributed between the brightness calculation unit and its adjacent brightness calculation unit.

(Example) Fig. 1+11), (bl is a block diagram showing an object image synthesis device as an embodiment of the present invention, Fig. 1 f
FIG. 1(a) is an overall configuration diagram showing the entire object image synthesis device, and FIG. 1(b) is a configuration diagram showing the detailed configuration of the brightness calculation section. As shown in FIG. 1 (al), an initial ray generating section 1 is provided which generates information on a plurality of rays passing through each pixel of an image to be synthesized from a preset viewpoint.

Further, an object information setting section 2 is provided for setting information about the object to be displayed.

Furthermore, taking charge of one region out of a plurality of regions generated by dividing the space in which the object is defined, and performing intersection determination processing between the light ray passing through this region and the object included in the assigned region. Additionally, a plurality of brightness calculation units 3 are provided to calculate the brightness of each pixel. This brightness calculation section 3
An image storage unit 4 that stores the calculated brightness as an image.
is provided. The image storage unit 4 sets all luminances to O before combining images.

Then, these initial ray generating section 1 and object information setting section 2
A connecting line 5 is provided for transmitting information between the plurality of brightness calculation units 3 and the image storage unit 4. This connection line 5
An information input unit 6 is provided for inputting information from, for example, a keyboard.

As shown in FIG. 1 (bl K), the brightness calculation unit 3 is provided with mutual communication means 31 that communicates with the brightness calculation units 3 that are in charge of areas adjacent in six directions. A communication means 32 is provided for communicating via the connection line 5. Furthermore, a connection line 101 is provided for transmitting information within the brightness calculation section 3.

FIG. 2 is a diagram for explaining a method of calculating the volatility of pixel p (i, j). As shown in FIG. 2, in the ray search method, the path of the ray from the light source through the pixel p (1, j) to the viewpoint E is traced in the opposite direction, and the pixel p (i
, j) is calculated. Here, pixel p (i,
The luminance factor j) will be referred to as the luminance of the light ray R generated in the opposite direction from the viewpoint E through the pixel P (ITJ). The brightness of this light @R is the intensity I of the light that passes through the pixel p (i, j) and enters the viewpoint E. The brightness of light mR is
It is calculated using the following formula.

I = ref umbrella I' + dH books (N-RL
) Umbrella 1l-ref: Reflection coefficient dif of object O: *Diffusion coefficient I' of body O: Incident light intensity from the R' direction IL: Incident light intensity from the light source N: Unit normal vector of the surface of object O R': R
Specular reflection direction vector RL: Direction vector of the light source To find the intensity of these two incident lights I', IL, we define two light rays R', RL whose starting point is the intersection CP and whose directions are R', RL. generate. In addition, the coefficients of I' and +L for determining the luminance coefficient are
, GL. In other words, the ray R is the object 0
The light rays R' and RL are attenuated by colliding with the light rays R' and RL. These attenuation rates G' and GL are as follows: G' = G*ref GL = G dif umbrella (N-RL) G: Attenuation rate of light ray R (=1). By using these attenuation factors G' and GL, the brightness factor of the light ray R, that is, the brightness factor of the pixel p (i, j) can be obtained as follows.

I=G'umbrella 1'+G, umbrella IL In this way, when new rays R'' and RL are generated, information about ray R is no longer necessary.

Furthermore, as shown in FIG. 2, when the ray R' intersects the object O', rays R'' and RL are similarly generated. It is calculated by the following formula.
) ref': Reflection coefficient of object O'dir': Diffusion coefficient of object O' No.: Unit normal vector R% of the surface of object O'
Directional vectors of two light sources In this way, attenuation rate G'' and GL' have attenuation rate G.

is accumulated.

However, the processing of the light ray RL is different from that of the light rays R and R'.

When the light ray RL intersects an object, the intersection point CP is in the shadow of the object and cannot receive the illumination light of the ray. Therefore, the brightness IL of the light ray RL is O. If the ray R
If L does not intersect any object, the intensity IL of the light fQRL will be the brightness of the light source. In this way, the light ray R1R° toward the object and the light 11g1 toward the light source! Since it is treated differently from RL, it is necessary to distinguish fM@ of the light ray. Therefore, a type C is set for the light ray R to distinguish the type of light ray. This type C is given a value of 1 when the ray R is directed toward an object and when it is directed toward the O1 light source.

As shown in FIG. 2, a ray of light directed toward an object generates a ray of light directed toward another object each time it collides with an object. Therefore, in order to calculate the slope I of one pixel p, many light rays may have to be processed. However, each time the light ray collides with an object, it is attenuated, so as the number of collisions increases, the effect of the light ray on the luminance becomes almost negligible.

Therefore, in order to limit the number of collisions of the ray R, a number T is set for the ray R. This number T indicates the number of possible collisions of the ray R. When a ray R with a number of times T collides with an object and a ray R° directed toward the object is generated, the number T° of the ray R' is set to (T-1). If the ray R collides with an object the number of times T is O, the ray R' directed toward the object is not generated, but only the ray RL directed toward the light source is generated.

In addition, in the tII22 diagram, there is only one light source Li, but if there are multiple light sources Li (i = 1.2...), it is necessary to generate light rays directed to all the light sources Li. It won't happen. By the way, in the case of the light ray RL heading toward the light source, no new light ray is generated even if it intersects with an object, as described above, so the number of times T as information about the light source RL has no meaning. Therefore, when a plurality of light sources Li exist, the number i of the light source to which the light aRL is directed is set as the number T of light ftJj RL.

By setting the number of times T of the light rays RL in this manner, even if there are a plurality of light sources Li, the number i of the light source to which each light ray RL is directed can be known, so that processing can be performed correctly.

Also, here, for simplicity, only reflection on the surface of the object was considered. If transmission through the object is also taken into consideration, it is sufficient to generate a ray in the transmission direction at the intersection of the object and the ray R. However, this type of light ray is a ray directed toward an object, and if it is processed in the same manner as the above-mentioned ray R', the transmission of the object can be accurately expressed.

FIG. 3 is a diagram showing information on the ray R that should be set when the ray R is generated. As shown in FIG. 3, when the light dR is generated, the information about the light ray R is the starting point position coordinates (Sx, Sy) of the half straight line indicating the light ray R.

S,) and direction (dx, dy#d,) are set.

Further, the position (i, j) of the pixel p (i, j), which is affected by the brightness of the light ray R, is also set as information about the light ray R. Furthermore, the attenuation rate G of the ray R, the number T of the ray R, and the ray R
The type C of is also set as the information of the light ray R.

FIG. 4 is a diagram for explaining the operation of the initial beam generating section l.
It is an explanatory diagram. As shown in FIG. 4, the initial beam generating section 1
, a light ray R is generated on an extension of a half straight line starting from the viewpoint E and passing through each pixel p (IIj) constituting the image P.

For this purpose, the initial ray generating section 1 shown in FIG.

Ey, E, ") is input. Also, the image P to be synthesized
As information defining the image P, parameters indicating the plane and range of the image P are input from the information input unit 6.

The initial ray generating unit 1 generates information about the light iR based on these parameters. An example of a method for finding a half-line indicating the ray R is the method used by T.
, Whitted), Communication of A.
CM), Volume 23, No. 6, pp. 343-349, Paper [An In-groove Illumination Model for Shaped Display (An
Improved 111uminationMode
1 for Shaded Display) J.

Next, among the intersections between this half-line and the object definition space, the position coordinates (Sx, Sy) of the intersection closest to the viewpoint.

Find Sz). These position coordinates (SX, Sy, S2) become the starting point position coordinates (Sx, Sy, S2) of the light ray R.

That is, the position where the ray R first enters the object definition space becomes the starting point of the ray R. Also, the direction from the viewpoint E toward the pixel p is the direction of the light ray R (dx, dy).

d2). Furthermore, the position (I
Ij) is light, 13R pixel position tff (i, j
).

In the initial light beam generating section 1, the attenuation rate G of the generated light IR is set to 11, that is, a state where the light IR is not attenuated at all. Further, as the number of times T, a constant value set in advance is given to the initial light beam generation section 1 from the refresh report input section 6. Further, as type C, a value of 0 is given, which indicates a ray of light directed toward an object.

In the initial light beam generation section 1, a light beam R having such information is generated corresponding to all the pixels p(+, j) of the image P, and is transferred to the brightness calculation section 3.

FIG. 5 is an explanatory diagram showing the object information set in the object information setting section 2. As shown in FIG. To simplify the explanation, the displayed object will be limited to a sphere, but the same method can be used when displaying objects such as polyhedrons and free-form surfaces.

As shown in FIG. 5, object information is input from the information input section 6 and set in the object information setting section 2. As shown in FIG. The information on the amount of the object to be set is the object number ni for distinguishing the object i.
, the center coordinates of the sphere as an object ("i+Y1, zi
) *Radius ri, diffusion coefficient difi indicating the material of the object
, the reflection coefficient r e f 1. Further, as information indicating the circumscribed area of the object i, the range of the smallest rectangular parallelepiped including the object is set.

FIG. 6 is an explanatory diagram showing a circumscribed region of a sphere as an object. As shown in FIG. 6, the circumscribed area of object i is the range in the X direction (Xl-1X10L) and the range in the direction (yi-
+7i10L It is a rectangular parallelepiped indicated by the range (zi-+zi+) in the Z direction. These values are obtained using the following equations.

X・ =Xi J xi+1 1 7i-=3'i -ri yt+= yt + ri "i-"zi'i Zl+ = zl+ ri FIG. 7 shows the light source information set in the object information setting section 2 , is an explanatory diagram. To simplify the explanation, the explanation will be limited to point light sources, but the same procedure can be applied to various types of illumination light such as parallel rays and spotlights. As shown in FIG. 7, information on a light source for illuminating an object is input from the information input section 6 and set in the object information setting section 2. The information on the light source that is set is the position coordinates (xi, 7t *J) of the point light source l *the brightness ILi of the light source. This brightness ILi is a real value between 0 and 1. The value of brightness + indicates the brightness of the light source, and when it is 1, it is the brightest, and when it is 0, it is a completely dark light source.

The object information and light source information thus set are transmitted from the object information setting section 2 to the brightness calculation section 3 via the connection line 5.

FIG. 8 is an explanatory diagram showing a method of combining a plurality of brightness calculation units 3 into a three-dimensional array. As shown in FIG. 8, the brightness calculation units 3 are connected in a three-dimensional array via mutual communication means 31 provided within the brightness calculation units 3. That is, each brightness calculation unit 3 is connected to the brightness calculation units 3 on both sides in the x, y, and z directions, and these brightness calculation units 3
information can be mutually transmitted. Here, X *
7 The a, b, and c-th brightness calculation units 3 in the t2 direction are
.

b, c) If we call it the brightness calculation unit 3, (a.

b, e) The brightness calculation unit 3 calculates (lk l * b e
C) +(a+1+b+e)+(a*b-1ee)*(
'+b + 1 * e ) + (& * b e
e 1 ) * (a e b * c + ) #l
It is connected to the evening calculation section 3.

Further, the brightness calculation units 3 are arranged in A, B, and 0 units in the X and 7.1 directions in the figure, respectively, and the total number of the 30 brightness calculation units is as follows: D=A umbrella B*C.

FIG. 9 is an explanatory diagram showing a method of dividing a space defining an object into areas S assigned to each brightness calculation unit 3. As shown in FIG.

The object definition space is divided into a plurality of rectangular parallelepiped-shaped regions by planes perpendicular to one axis of the V t z coordinate axes. In this case, the number of regions in the X direction is A.

The division is performed so that the number of regions in the X direction is B and the number of regions in the two directions is 0. Then, the third area in the X direction, the fifth area in the X direction, and the 0th area in the two directions are assigned to the (a + b rC) brightness calculation unit 3. With this, all the divided areas can be assigned to one brightness calculation section 3, respectively.

Moreover, by performing such allocation, the brightness calculation units 3 connected via the mutual communication means 31 will respectively draw adjacent areas.

FIG. 10.11 is an explanatory diagram showing the contents of area information indicating the area S in charge of the brightness calculation unit 3. As shown in FIG. 10, area information storage means 33 provided in the brightness calculation section 3
Area information indicating the area S in charge of the brightness calculation unit 3 is stored in . This area information includes the values (a, b, c) indicating the order number in the X, y, and Z directions, and the range (X
-IX+L(y+, )'10), (z-, Z+
) are stored.

Furthermore, in the brightness calculation units 3 existing on the outer periphery of the three-dimensional array, the brightness calculation units 3 may not be connected to the mutual communication means 31. Therefore, whether or not the brightness calculation section 3 is actually connected in each direction connected by the mutual communication means 31 is stored in the area information storage means 33 as presence/absence information.

These area information are input from the information input means 6,
It is transmitted to each brightness calculation unit 3.

FIG. 12 is an explanatory diagram showing the process of transferring information about the light ray R from the initial light generation section 1 to the brightness calculation section 3. As shown in FIG. 12, information on all the rays R generated by the initial ray generating section 1 is transferred to all the luminance calculating sections 3 via the connecting line 5. Information on the light ray R transferred from the initial light generation section 1 is inputted to the light ray information determination means 37 provided in each brightness calculation section 3 via the communication means 32. At the same time, the information on the assigned area S stored in the area information storage section 33 is read out by the light beam information determining means 37. The starting point position coordinates (Sx
, Sy, S2) are set at positions where the ray R first enters the object definition space.

Therefore, if this starting point position coordinates (Sx, Sy, S2)
is included in the assigned area S, the light ray R will pass through the assigned area S first.

Therefore, the light ray information determining means 37 uses the starting point position coordinates (sx, sy, s,) of the light ray R and the range (x-x
+), (y +y+)t(z sz+) are compared.

If all three conditional expressions: It is
The light ray R will first pass through the assigned area S. In this case, the information on the light 7aR is transferred from the light beam information determining means 37 to the light beam information storage means 34 and stored therein.

Furthermore, if any of these conditional expressions does not hold, it means that the light ray R is first incident on another assigned area S'. Therefore, information on the light ray R is not stored in this brightness calculation section 3.

Through the above processing, information on the light ray R generated by the initial light generation section 1 is stored in the light ray information storage means 34 of the brightness calculation section 3 which is in charge of the first incident area.

FIG. 13 is an explanatory diagram showing a process of storing object information and light source information from the object information setting section 2 in the object information storage means 35 and light source information storage means 36 provided in the brightness calculation section 3. . As shown in FIG. 13, the object information setting section 2
All object information and light source information stored in the connection line 5
The brightness calculation unit 3 is simultaneously transferred to all the brightness calculation units 3 via. The light source information storage means 36 provided in the brightness calculation section 3 stores all the light source information transferred via the communication means 32.

Further, object information determination means 38 provided in the brightness calculation section 3
First, the object information transferred via the communication means 32 is received. Next, the range of the area S in charge of the brightness calculation section 3 is read out from the area information storage means 33. The range of this responsible area S (x-, X+) + (y-+y1L (Z-, z-4-
) and the range of the circumscribed area of the object information ("i +"i + LO
'i +yi+) and (zi +zi+) are compared.

FIGS. 14(a) and 14(b) are explanatory diagrams showing a comparison process between the area S in charge of the brightness calculation unit 3 and the circumscribed area of the object information. As shown in Figure 14(a), (bl),
When the assigned area S and the circumscribed area have no common part, at least one of the following conditional expressions is satisfied.

X-≧XI+ It is determined whether the region S and the circumscribed region have a common part. As a result, if there is a common part, it is determined that the object 1 is included in the assigned area S, and all information about the object 5 is stored in the object information storage means 35. If they do not have a common part, they are not stored.

Through the above processing, among the object information stored in the object information setting section 2, only the object information included within the assigned area S is stored in the object information storage means 35 provided in the brightness calculation section 3.

FIG. 15 is an explanatory diagram showing the process of changing the area S in its duty by the brightness calculation unit 3. This process of changing the assigned area S is performed by moving the boundary surface of the assigned area S perpendicular to a specific coordinate axis in a direction parallel to this specific coordinate axis. This specific coordinate axis is determined by information input from the information input section 6. Here, a case will be explained in which two coordinate axes are specified as specific coordinate axes, but this does not impair film properties.

As shown in FIG. 15, the load determination means 43 provided in the brightness calculation section 3 determines the number of lights lsR stored in the light beam information storage means 37 as the load F of the R variation calculation section 3. The load F determined by this load determination means 43 is transmitted to the brightness calculation section 3 (z-4-) connected to the 2+ direction of the brightness calculation section 3 via the mutual communication means 31, and to the brightness calculation section 3 (z-4-) connected to the 2+ direction of the brightness calculation section 3. The brightness calculation unit 3 (z--) is transmitted to the brightness calculation unit 3 (z--). and,
The load comparison means 44 includes the brightness calculation unit 3 (z-), (z+)
The load F(z
-), F(2+) and the load F determined by the load determining means 43 are compared. As a result of comparing the loads, the comparison result dF determined by the load comparison means 44 as follows:
aF10 is output.

When F(z-) −F )TH, dF = 1
When F-F(z)>TH, dF-=-1; otherwise, aF=.

F(Z+) −F > TI(when dF+=1
When F −F(z+)>TH dF+=-1 Otherwise dF+=O TH: Positive threshold value set in advance through the information input unit 6 When the comparison results dF and dF+ are 1, the assigned area S
is expanded, and when it is -1, it indicates that the responsible area S is shrunk.

In response to the load comparison result determined in this way, the area changing means 45 changes the range of the area S in charge. The area changing means 45 first reads and stores the two-direction range (z, z+) of the area S in its duty from the area information storage means 33. Next, we create a new range (z' −
+z' +).

z' = z dF -ADSz'-
4-=z++ dF+*ds dS: Positive movement amount set in advance through the information input section 6 The range (Z'IZ'+) obtained in this way is
It is written in the area information storage means 33 to change the range of the area S in charge. Such a change in the assigned area S is carried out independently in each brightness calculation unit 3, but since the same processing is performed simultaneously, the assigned area S is changed without any contradiction.

By performing such change processing of the responsible area S,
The number of objects included in each assigned area S and the number of light rays passing through can be changed. Therefore, each brightness calculation unit 3
Since the amount of calculation can be changed, the total calculation t
' can be averaged to achieve appropriate load redistribution.

In changing the assigned area S in this way, the area removed from the assigned area S is called a decreased area S-1, and the area added to the assigned area S is called an increased area S+.

When the assigned area S is changed, the object/news storage means 35
It is necessary to change the information on objects included in the assigned area S that is stored in .

First, when dF- is -1, the area changing means 45
- and the range of the reduced area S- by the object information determining means 38.
Output to. Upon receiving this, the object information determining means 38 reads out the changed range of the area S in its duty from the area information storage means 33 and stores it.

Then, the information of the object i is read out one by one from the object information storage means 35, and the circumscribed area of the object 5 is reduced to the reduced area S-
Determine whether there is a common part with.

The determination process at this time is performed in the same manner as already explained with reference to FIG.

If the circumscribed area of this object l has a common part with the reduced area S-, information about this object l is transferred to the brightness calculation unit 3(z-) via the mutual communication means 31. At the same time, it is determined whether or not the assigned area S, which has been changed by 1, and the circumscribed area of this object i have a common part. If there is no common part, the information of this object l is stored in the object information storage means 35.
Delete from.

Further, when dF- is 1, the area changing means 45
Only the value of F- is output to the object information determining means 38. Upon receiving this, the object information determining means 38 reads, via the mutual communication means 31, the information on the object j transferred from the brightness calculation section 3 (2-).

The information about this object j is calculated by the brightness calculation unit 3 (z-),
This is information that was determined to be included in the increased area S+ and transferred, and is an object included in the changed area S.

However, information about the same object as this object j may already be stored in the object information storage means 35. Therefore, in order to avoid storing information about object j repeatedly,
Object number n of this object j.

and the object number nl of the object i stored in the object information storage means 35. Depending on the result of this comparison, if the object is
If the same object 1 is not stored, the information about object j is stored in the object information storage means 35.

Furthermore, similar processing is performed for dF+ to change object information.

Through the above processing, when the assigned area S is changed, the object information stored in the object information storage means 35 is changed.

FIGS. 16(a) and 16(b) are explanatory diagrams showing a method of transferring information on the light ray R between the brightness calculation units 3. Figure 16+
As shown in a), changing the assigned area S causes a shift in the boundary surface of the area. In addition, as shown in FIG. 16 (bl), the connection of the brightness calculation unit 3 rbM via the mutual communication means is fixed. Therefore, in the case shown in FIG. Information on the light ray R that enters the assigned area sb from Sa cannot be directly transferred from the brightness calculation section 3a to the brightness calculation section 3b via the mutual communication means 31.

Therefore, such information on the light ray R is first sent to the brightness calculation unit 3.
a to the brightness calculation unit 3cK via the mutual communication means 31.
be transferred. This transferred information on the light ray R is once transferred to the brightness calculation section 3C. This transferred light? sR
The information is temporarily stored in the light beam information storage means 34 of the brightness calculation section 3c.

The information on the light ray R stored in the leading information storage means 34 in this way is first read out to the light ray information determination means 37. The light beam information determining means 37 compares the two coordinate values S2 of the starting point position coordinates of the light beam R with the two-direction range (z Iz+) of the assigned area S read from the area information storage means 33.

If S2≧2+, information on the light ray R is transferred via the mutual communication means 31 to the brightness calculation unit 3d connected in the 2+ direction. Furthermore, if S<z-, information on the light ray R is transferred to the luminance calculation section 3c connected in one direction via the mutual communication means 31.

In other words, since only the range (zlZ+) in two directions of the area S in charge is changed, if the information on the ray average is transferred to the brightness calculation unit 3 connected in two directions, the correct brightness calculation unit 3 can calculate The information of the ray R can be processed.

FIG. 17 is an explanatory diagram showing a method of calculating the brightness of each pixel by the process of determining the intersection between a light ray and an object in the brightness calculation unit 3. As shown in FIG. 17, the information on the ray R stored in the ray information storage means 34 is first stored in the ray information determining means
is read out. As a result of the determination process in the light ray information determining means 37, information on the light ray R that has not been transferred to the brightness calculating section 3 (z-) or the brightness calculating section 3 (z-1-) is sent to the intersection determining means 39. This intersection determination means 39 is
Intersection determination processing between the light ray R and the object stored in the object information storage means 35 is performed.

Furthermore, for the ray RK that does not intersect with the object, the intersection of the ray R and the boundary surface of the assigned area S is first determined. From this point of intersection, the region S' into which the light ray R will next enter is determined, and the direction in which information about the light ray should be transferred is determined. Light, IJ
The information on R is transferred to the brightness calculation unit 3 in the determined direction via the mutual communication means 31.

At this time, the starting point position coordinates of the light ray R are changed to the position coordinates of the obtained intersection point. As a result, the starting point position coordinates of the light ray R will be included in the area to which the light ray R should enter next.

The information of the light ray R transferred in this way is transmitted to the mutual communication means 31
, and stored in the light beam information storage means 34.

Furthermore, when the ray R intersects an object and a different ray R° or ray RL is generated from the ray R, the information on the ray R°, the light, and the gland RL is stored in the ray information storage means. 34
is memorized.

Such intersection determination processing is shown in each of the aforementioned papers and FIG. 2.

When the brightness I of the light ray R is determined by this process, the luminance value is added to the pixel p (i, j) of the image storage unit 4 indicated by the information about the light ray R via the communication means 32. be done.

The synthesis of the image P is completed when all the information on the light rays R stored in the light ray information storage means 34 of each brightness calculation section 3 has been processed by the above-described intersection determination process.

(Effects of the Invention) In the object image synthesis device of the present decoy, the shape of the area in charge of each brightness calculation section is a rectangular parallelepiped, and each surface of the rectangular parallelepiped is perpendicular to the coordinate axis. Therefore, it is very easy to determine the intersection between the boundary surface of the assigned area and the light beam. Therefore, when a light beam passes through the assigned area, it is possible to determine the area to which the information of this light beam should be transferred with a much smaller amount of processing than in the past.

In addition, the shape of the area in charge can be changed by moving the boundary surface perpendicular to a specific coordinate axis in a direction parallel to that coordinate axis.
executed. Therefore, even if the shape of the area in charge is changed, the area in charge is kept in the shape of a rectangular parallelepiped, so the above-mentioned effects are not impaired.

Furthermore, when the shape of the assigned area is changed, the information on objects included in this assigned area must be changed.

Even in this case, since the area in charge is kept in the form of a rectangular parallelepiped, object information can be easily changed.

In this way, since the amount of processing required when changing the shape of the assigned area is small, it is possible to sufficiently obtain the effect of redistributing the load of each brightness calculation unit by changing the shape of the assigned area.

[Brief explanation of drawings]

FIG. 1(a) is an overall configuration diagram showing the entire object image synthesis device, FIG. 1(b) is a configuration diagram showing the detailed configuration of its brightness calculation section, and FIG. i, j) brightness I
Fig. 3 is an explanatory diagram showing the calculation method of ``/l'' which should be set when the ray R is generated, an explanatory diagram showing information on the winning R, Fig. 4
5 is an explanatory diagram showing the object information set in the object information setting section 2, and FIG. 6 is an explanatory diagram showing the object information set in the object information setting section 2. FIG. FIG. 7 is an explanatory diagram showing the information on the light source set in the object information setting section 2, and FIG. 8 is an explanatory diagram showing the circumscribed area of the object information setting section 2. FIG. Explanatory diagram showing, No. 9
FIG.
0.11 is an explanatory diagram showing the contents of area information indicating the area S in charge of the brightness calculation unit 3, and FIG.
FIG. 13 is an explanatory diagram illustrating the process of transferring the information of Kohi R from to the brightness calculation unit 3. FIG. FIG. 14(a) is an explanatory diagram showing the process of storing object information and light source information from 2 to 3.
FIG. 15 is an explanatory diagram showing the process of comparing the responsible area S of the object information with the circumscribed area of the object information. FIG. teeth,
FIG. 8A17 is an explanatory diagram showing a method of transferring information of light @R between the brightness calculating units 3. FIG. In the figure, 1... Initial ray generation section, 2... Object information setting section, 3
゜3a, 3b, 3e, 3d--luminance calculation section, 4...
Image storage section, 5... Connection line, 6... Information input section, 3
1... Mutual communication means, 32... Communication means, 33-
... Area information storage means, 34... Ray information storage means,
35...Object information storage means, 36...Light source information storage means, 37...Light ray information determination means, 38...
Object information determining means, 39... Intersection determining means, 43...
・Load determination means, 44-...Load comparison hand G/'
J e--1eM4-ayh<'rMd knee%tn
＊---- Ichihan 1 Figure (a) E〉(s4D"'FA'fi-': I'-3 Trap Kocho eL
s1υ5'-'&IIsiCn amount.

Claims (1)

[Claims] The above image is created using the ray tracing method, which traces the path of the light ray from the light source to the viewpoint in the opposite direction, performs intersection determination processing between the object and the light ray, and calculates the brightness of each pixel that makes up the image that should display the object. an initial ray generation unit that generates information on a plurality of rays passing through each pixel from the viewpoint in order to perform synthesis; an object information setting unit that sets information on the object;
By taking charge of one region out of a plurality of regions generated by dividing the space in which the object is defined, and performing intersection determination processing between a ray passing through this region and an object included in the said region. In an object image synthesis device comprising a plurality of brightness calculation units that calculate the brightness of the pixels, and an image storage unit that stores the brightness calculated by the brightness calculation units as the image, the brightness calculation unit includes the Area information storage means for storing the range of the area in charge of the brightness calculation unit among the plurality of areas generated by dividing the object definition space along a plane perpendicular to the coordinate axes, and a load for determining the load of the brightness calculation unit. a determining means, mutual communication means for mutual communication between the brightness calculation section and an adjacent brightness calculation section that is in charge of an area adjacent to the responsible area in a direction parallel to a specific coordinate axis; a load comparison means for comparing the load of the adjacent brightness calculation section and the load of the brightness calculation section; and a load comparison means for comparing the load of the adjacent brightness calculation section with the load of the brightness calculation section; an object image comprising: area changing means for changing the range of the area in charge stored in the area information storage means to change the shape of the area in charge by moving in a parallel direction; Synthesizer.