JPH04169980A - Rendering device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rendering device, and in particular, to computer graphics (CG) image production, such as CG calendar, CG hologram, CG animation, CG
The present invention relates to a rendering device suitable for use in producing commercials, CG posters, or high-definition CG still image programs. [Prior Art] A computer system that generates figures and images within a computer.
Today, graphics (CG) technology is becoming faster and more dense due to the increasing functionality of computers, lower prices of memory, and larger capacity. For this reason, the CG image is 5. It can be used in many fields such as video media information, high-definition still image programs, and print image information. A CG image generated by a computer is an image that displays a scene captured by a camera by shining a certain light onto an object. In the generation of C0 image data, it is usual to generate information about the object (CG model), and perform various processing on the generated CG model to display the object shape as an image. be. The CG model generally includes shape data of an object to be generated, for example, shape data represented by a collection of surfaces;
The three-dimensional position data of the object shape and the image of the object (
(virtual) camera information, such as camera position information consisting of the camera position (view point) and camera direction (point of gaze), camera information consisting of the camera's angle of view and aspect ratio, and texture information of the object, such as environmental reflection. It mainly consists of light information for irradiating light onto the object, such as the three-dimensional position and type of the light, and information on the type of mapping. Rendering of the CG model generated in this manner is generally performed by a rendering system that is integrated with the CG model generation system. Also, the CG model is generated by a certain system A, and the CG model is
It is desired that the G model be rendered by another system B. In particular, if system B has a high processing speed, system A
In some cases, it may be desirable to process object information produced by another system B, which is faster than system A. In this case, in the CG model, the shape data produced by system A can be passed to system B for processing.
This is commonly done. [The problem that the invention tries to solve! ! l! ! However, conventionally, it has not been possible to pass data regarding other CG model parameters (texture parameters, light source parameters, mapping parameters, etc.) for rendering due to differences in shadow calculation models between systems. Therefore, conventionally, if you wanted to process a CG model produced by a certain system A in a high-speed system B, only the shape data could be passed to system B, and the data of other CG models had to be newly produced in system B. That's all I can do. Therefore, for example, it is not possible to render a CG model previously created using a slow old system on a new high-speed system, and the model has no choice but to be rendered on a slow system, making it difficult to speed up CG production. There was a problem. In addition, in the production of CG images, CG images other than shape data
Regarding models (texture models, etc.), it is necessary to generate different CG models for each CG day production system, which poses a problem in that the workload is extremely large. In addition, the CG model information of a certain system A includes system A.
There is a problem in that when reading from a file, there is information that is difficult to use as is due to the information format. The present invention was made in order to solve the above-mentioned problems of the conventional system.
An object of the present invention is to provide a rendering device that can perform conversion for use in a system such as the above, and can therefore produce C0 image data at high speed and utilize the C0 image data over a wide range of areas. Means for Solving the Problems The present invention provides a computer graphics system that includes object shape information, camera information, camera position information, light source position information, object shape position information, texture information, and A device for rendering a computer graphics model consisting of light source information, mapping information, etc. with a second system having a different shading calculation model from the first system, and inputting texture information of the first system. means for inputting light source information of the first system and converting it into texture information for the second system; and means for inputting light source information of the first system and converting it into light source information for the second system; an interface section for absorbing differences in the shading calculation model; The above problem is solved by including means for converting information read in an information format different from the information format of the interface section into the information format of the interface section. [Operation] Computer graphics (CG) of the first system
) model cannot be used as a CG model for a second system whose shadow calculation model is different from that of the first system. In contrast, the present invention inputs the texture information of the first system and converts it into texture information for the second system, inputs the light source information of the first system, and converts the texture information to the light source for the second system. The mapping information of the first system is inputted and converted into mapping information for the second system, thereby absorbing the difference in the shading calculation model. Further, among the information read out from the first system, information read out in an information format different from the information format of the interface unit, such as camera information, camera position information, light source position (three-dimensional position, etc.), and object shape position. (3-dimensional position il!f), and the interface section cannot perform conversion at t and t. Therefore, the present invention describes the read information in the information format of the interface section. Therefore, since the CG model generated by the first system can be passed to the second system for rendering, the CG
Manufacturing efficiency is improved. Therefore, there is no need to set different CG production parameters for the various systems A, B, . . . , which reduces the workload. Furthermore, there is no need to store and manage CG production parameters for each system. Furthermore, CG image data previously produced using a low-speed system can be used for rendering using another high-speed system. Therefore, it is possible to transfer to the new system without losing the CG production know-how accumulated with the old system. Furthermore, as computers become faster, the speed of the CG system can be increased freely. Furthermore, it is possible to effectively utilize CG models that have been stored for a long time to perform various renderings. Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. This embodiment is a rendering system configured as shown in FIG. As shown in FIG. 1, this rendering system uses C
System A (symbol 1) that generates a G model, and system B (symbol 2) that has a different shading calculation model from system A.
, an information format conversion unit 4 for reading camera information object shape data etc. from system A and converting it to the information format of the interface unit 3, and a CG model generated by system A to system B. Differences in shading calculation model It mainly includes a rendering interface section 3 for absorbing and passing on the information. The system A is for generating a CG model, and includes a shape design specification unit 6 for designing and specifying the shape of an object to be displayed in CG, camera information, camera position information, and light source (light) information. Camera/light source/shape position information specifying unit 7 for specifying position information and object shape position information
and a texture/light source/mapping information specifying unit 8 for specifying texture information, light source information, and mapping information of the surface of the shaped object. In the embodiment, the object shape is represented by a collection of surfaces, and the surface is represented by a collection of vertex information (X, Y, Z coordinates). Further, the object shape position is expressed by a three-dimensional position (X, Y, Z coordinates). Further, the camera information consists of the angle of view and aspect ratio of the camera used to photograph the object. Further, the camera position information consists of the camera position (viewpoint) and the camera direction (point of gaze), and the texture information includes the environmental reflectance Ka of the surface, the diffuse reflectance Kd of the surface, and the surface's diffuse reflectance Kd. Specular reflectance KS, specular reflection coefficient eXp, transmittance tra
It is expressed by each parameter (texture parameter) for Further, the light source information includes the type of light source (point, spot,
parallel), color, intensity, position (3-dimensional position, X, Y, Z%
(standard) and each parameter regarding the attenuation rate (light source parameter). Further, the mapping information is represented by a mapping image consisting of the type of pine pink (texture, bump, etc.) and the size of the mapping. These contents will be explained in detail later. The information format conversion unit 4 converts the information format of the interface unit when the camera information, camera position information, three-dimensional position information of a light source, and three-dimensional position information of an object generated by the system A is read out. Since the information is read in different information formats, this information is converted into the information format of the interface section 3 and sent to the interface section 3. The interface section 3 has a detailed configuration as shown in FIG.
The model is changed to System B by absorbing the differences in the shading calculation model.
It is to be given to. The system B performs rendering on the CG model converted by the interface unit 3. For example, a two-buffer method, a ray ranging method, etc. can be used for this rendering. Here, the detailed configuration of the interface section 3 will be explained in the second section.
This will be explained using figures. The interface unit 3 in FIG. 2 includes a texture model reading storage device 10 for the system A for reading texture parameters, pine pink images, and light source parameter data (hereinafter referred to as texture model) among the CG models generated by the system A. , object shape data of the CG model, shape data for inputting data of the three-dimensional position of the object shape, shape position input device 12, camera information of the CG model, camera information for inputting the camera position. , camera position input bag f38, and a texture model reading/storage for system B for reading and storing the data that has undergone predetermined conversion and has become texture model data for system B from among the CG models produced by system A. a device 14, a rendering interface (I/F) device 18 for converting the texture model for system A into a texture model for system B and passing it to system B; and a shape stored in the device 12. data, shape position data, camera information stored in the device 38, camera position data, system B stored in the device 14
It mainly includes a system B (projection image creation device) 16 that reads texture model data and performs rendering processing. The texture model reading and storing device 10 for system A includes a texture parameter reading and storing section 20, a mapping image reading and storing section 22, and a light source parameter reading and storing section 24 for reading and storing each parameter. The system B texture model reading and storing device 14 also includes a texture parameter reading and storing section 26, a mapping image reading and storing section 28, and a light source parameter reading and storing section 30 for reading and storing each passed parameter. Be prepared. Furthermore, in order to pass the texture model for system A to the texture model for system B, the rendering I/F device 18 includes a texture parameter converter 32 for converting each parameter, a mapping image converter 34, and a light source. and a parameter conversion section 36. In this embodiment, the camera information inputted into the camera position storage device 38 represents the angle of view and aspect ratio of the camera. In addition, the camera position includes the three-dimensional position of the camera (viewpoint) and the three-dimensional direction of the camera (point of gaze).
Let it be expressed as Next, the texture models for system A and system B and the receiver of these texture models are used by the rendering I/F device 18 to absorb differences in the shading calculation models between the systems A and B. An example of a conversion formula will be explained below. First, the texture parameter converter 32 converts texture parameters as follows. In this case, for each texture parameter for system A, as shown in Equations (1) to (5), Equation (1): Environmental reflectance of the surface (aI!b 1ent ; a ), (2); Diffuse reflectance (diffuse; +j), equation (3); specular reflectance of the surface (5 pecular+s), equation (4); specular reflection coefficient (exponent; exp), and equation (5); transmittance (transparency). Was. A red, A a-green. A blue-(1) A-σ-red, A d (lr6en
. A d blue-(2) A S red, A S Green. A s blue・(3) A eXp...
(4) A transparency
-(5) However, in formulas (1), (2), and (3), the youngest red is red, the green is green, and the youngest is blue.
indicates that it is for each color of blue. Further, as the parameter A-a~ of the environmental reflectance of the surface in equation (1), a parameter reflecting the reflectance based on experience can be used. Moreover, each texture parameter for system B is the environmental reflectance Aa of the surface in the texture parameter for system A.
etc., as in equations (6) to (10), equation (6):
Environmental reflectance of the surface, (7): Diffuse reflectance of the surface, equation (8);
The specular reflectance of the surface, the formula; the specular reflection coefficient, and (10
) formula; represents transmittance. Ba red, Ba queen. B a blue-(6) B d red, B d-green. B d blue-(7) B S red, B S-green. B s blue-(8) B 13XI)...
(9) B transparency
= (10) The formula for converting the texture parameters for system A as described above into texture parameters for system B is as follows. First, regarding the environmental reflectance of a surface, the conversion formula when no texture is attached to the surface includes, for example, equations (11) to (1).
3) can be used, and as a conversion formula when pasting a texture, for example, formulas (14) to (16) can be used. B a red = A a red
-(11) B a areeen = A a
areen-(12)B a blue=A
a blue −<13) B a re
d=A a red/A d red...
(14) B a green =A green /A d green
en... (15) B a blue=A a blue/A
d blue... (16) Also, regarding the diffuse reflectance, the one for system A is directly substituted for system B as in equations (17) to (19). B d red = A d red −(1
7) B d green = A d green
n −= (18)B d blue=A d
blue −<19) Also, the specular reflectance is calculated by the procedure shown in FIG. 3 (λ) to (C). In the procedure shown in Figure 3, first, an intermediate variable (intermediate variable) INS of specular reflectance and an intermediate variable nd of diffuse reflectance are set.
,. (Step 1) 1 Then, the memory variables d [0), d (1), (1 [2
] and specular reflectance memory variables 5(0), 5(1), s
(2) Store each data of each diffuse reflectance parameter Ad-~ and the specular reflectance parameter AS~ in (
Step 2). Next, the maximum value of the specular reflectance stored in memory variables s[0] to s[2] is entered into the intermediate variable is. Further, the array numbers 0 to 2 of the intermediate variable having the maximum value are assigned to the index JIS n1Jl. Further, the maximum value of the diffuse reflectance stored in the memory variables d[0] to d[2] is substituted into the intermediate variable 1d (step 3). Next, it is determined whether each intermediate variable rzd and Is is not 0 (step 4). If the result of the 0 determination is that any intermediate variable +1d, Its is 0, then
□ Proceed to step 5 shown in (C) and save each memory variable S [
0] ~ S [2] The specular reflectance (specular reflectance of system A) in [2] is used as the specular reflectance parameter Bs of system B.
- Substitute into ~ (step 5). In this case, if both the diffuse reflectance and the specular reflectance are 0, the only parameter is the environmental reflectance component. On the other hand, if the intermediate variables rad and Is are both non-zero, since both diffuse reflectance and specular reflectance exist and can be processed, the process proceeds to step 6 to continue the process. Next, the color matching coefficient td is obtained from equation (20), and for each color specular reflectance in the memory variables S [0] to S [2], each color diffusion of the memory variables d [0] to d [2] is calculated. Using the reflectance and color matching coefficient td, formula (21)
~ (23) °, and the converted value is stored in memory variable b
Put into each of s (o) ~ bs (2:l (step 6). td = (d (0) + d (1)〒d[:2)
)X2...(20) bs(0)=(d(1)+d[2))/ld+
s Co) ... (21) bs (1) = (d
Co)+d[2))/ld+5(1)...
(22) bs[2)= (d[:O) 10d[:j))
/ld10s [-23 (23) The conversion according to equations (20) to (23) adds an increase correction to each color data of specular reflectance by taking into account the diffuse reflectance of other colors. Next, using the number ff1s null that gives the maximum specular reflectance obtained in the previous step 3, the ratio of the specular reflectance of the number before correction S (Is null) and after correction bsCIIS nun ''J is calculated as (24 ) and enter the ratio in the variable coef (step 7). coef=s (ns null) /bs[ns
nul:1...(24) Next, in step 8), initialize as index J-〇, and normalize the corrected memory variable bs[j), as in equation (25), apply bsCj) to The variable co
Multiply e f and create new bsCj) (Step 9)
. bs(j) = bs(j) xcoef −
(25) Next, the value of the memory variable bs(j) after being multiplied by the variable coef using equation (25) is the maximum value of the specular reflection coefficient, 5.
(ns nun )” (
Step 10) If the result of judgment 4 is positive, put the maximum value 5 (is null) of the specular reflection coefficient into the correction memory variable bs(j) (step 11) and proceed to the next step 12; If the judgment result is negative, the memory variable bsCj) is left as is and the process proceeds to the next step 12, thereby normalizing the specular reflectance. That is, it is possible to prevent the maximum value of each color specular reflectance after correction from exceeding the maximum value before correction. Next, it is determined whether the value of memory variable bs(j) after conversion by the above equations (20) to (23) is smaller than the value of memory variable 5(j) before conversion (step 12) 0 judgment result is positive, 5 is added to the memory variable bs(j).
The value of (j) is entered (Stella 713), and if the judgment result is negative, the value of the memory variable bs(j) is left as is and the process proceeds to the next and subsequent steps. Next, the index j is incremented by 1 (step 14). If j times 3 holds as a result of the increment, then the next memory variable bscj) (''=1, then j=
2), return to step 9 and execute the processing procedure from step 9 onwards (step 15).
, On the other hand, if j<3 does not hold and j≧3, the process proceeds to the next step 16. Then the specularity parameters of the surface for system B (red)
Enter the value of the memory variable bs CO) in the B s red, enter the value of the memory variable bs [1) in the same parameter (green) B s green, and enter the value of the memory variable bs C in the same parameter (blue) B s blue.
2) Enter the value (step 16), this step 16
or by completing step 5, the specular reflectance of the texture parameters is determined by system A.
The conversion of the one for system B to that for system B is completed. Further, regarding the specular reflection coefficient A 8Xp, for example, the value for system A is converted into the value for system B using the following equation (26). B eXl) = A elXI) X215
- (26) The constant 215 in equation (26) is used to match the size of the highlight due to the difference in aperture of both systems, and was obtained empirically from various data. Of course, an appropriate value can be selected according to the characteristics of the system. Further, the transmittance A transparency is converted into the transmittance B transparency for the system B using, for example, the table shown in FIG. Note that the relationships shown in FIG. 4 are obtained by comprehensively considering various data, and appropriate values can be selected depending on the system. Mapping image conversion is performed as follows. In system A, the mapping image parameters are A c red and A cgre for red, green, and blue.
The parameters A a red, A d red, etc. of the environmental reflectance and diffuse reflectance when system A performs mapping are expressed by the formula (
27) to (32). A a red=A a redxA c
red...(27) A a gr138n =A a Qrln XA CQreen・
... (28) A a tllLIe=A a bl
ueXA Cblue... (29) A d red=A d redxA
c red... (30) A d green = A d (Jreen XA C-gr1
3en... (31) A d blue=A d blue
xA c blue... (32) Also, in the mapping image of system B, each red, green, and blue data is B c red, B c green, B
Set it to c blue. In this case, the environmental reflectance, diffuse reflectance parameters B a red, B d red, etc. when mapping is performed by the system B are calculated using the following equations (33) to (38). B a red=B c redxB a
rea −<33) B a Green=
B CQgreenXB a green
-<34) B a blue = B c b
bluexB a blue - (35)
Bdred=Bcred−
<36) B d vreen=B c qre
en ・(37) B d blue=B c
blue - (38) Therefore, the equations for converting the mapping image from one for system A to one for system B are the following equations (39) to (41). B c red = A c red x B d
red...〈39) B c green =A c area xB d areeen
...(40) B c blue = A c blueexB
d blue...(41) The conversion of the light source parameters is performed as follows.The light source parameters of system A are the position of the light (x. expressed in y, z coordinates) A
and - the direction of the light (expressed in X, v, z coordinates)
A nx, Any, A nz, and the light aperture is A-exp + light color (three primary colors red,
(represented by green, blue) is A red
, A oreen, A blue, type of light (parallel light, point light source, spot light source) A mo
In this case, it is assumed that the light source of system A is not attenuated. Also, the light source parameters of system B are the same as system A: the light position is B X, B Y, B-2, and the light direction is B nx, B ny, B nz.
, light aperture B13Xp, light color B red
, B green , B blue , light intensity B 1ntenSity , light type B
It is assumed that the light source of system B is attenuated by, for example, 1/distance. Therefore, to prevent it from getting too dark, the light intensity s rntensr
Think about ty. When converting, the light position (three-dimensional position), light direction, light aperture, light color, and light type are used as they are in system A, and only the light intensity is changed. Calculated as follows. In this case, the light intensity is defined as the distance between the light position and the nearest shape surface data. This is to match only the most conspicuous shape surfaces. The effects of the embodiment will be explained below. In the example system, CG models such as shape data, camera/shape position data, light source (light) parameters, texture parameters, mapping images, etc. generated for system A are
Instead of performing rendering on system A, rendering is performed at high speed on system B, which is faster. At this time, the CG model consisting of light, texture, and mapping information data created for system A is transferred to each system A and B. Convert to a CG model for System B so as to absorb the shadow calculation model. That is, the texture parameters are converted by the texture parameter conversion section 32 according to the above-mentioned equations (1) to (26) and the flowchart of FIG. 3, and are input to the texture parameter reading and storage section 26 for system B. Further, the mapping image is converted by the mapping image conversion unit 34 according to the above-mentioned equations (27) to (41) and input to the B system. In this case, when converting and processing the pine pink image, from the texture parameter reading storage unit 20,
Input the diffuse reflection parameter of the surface shown in equation (2). Regarding the conversion of the light source parameters, the light position, light direction, light aperture, light color, and light type are substituted as they are, and only the light intensity is newly calculated. In this case, the distance between the position of the light and the nearest spherical surface data can be taken as the intensity of the light. and,
Regarding the shape data and shape position, those data input into the shape data and shape position input device 12 are used as camera information, and the camera information and the data input into the camera position storage device 38 are used for the camera position, and the texture parameters are inputted into the camera information and camera position storage device 38. Using the data stored in the texture model reading/storage device 14 for system B, the projection image creation device 16 of system B performs rendering. Note that the details of the configuration of the projection image forming apparatus that is system B are described in, for example, Japanese Patent Application No. 149765/1982, and therefore detailed explanation will be omitted here. As described above, the texture model, shape data, etc. of system A are input to system B, thereby allowing system B to render the 00 image at high speed. Effects of the Invention As explained above, according to the present invention, the C0 image model produced by the first system is passed to the second system B, which absorbs the difference in the shading calculation model, and performs rendering. This improves work efficiency. Therefore, there is no need to set different CG production parameters for each system, which reduces the workload and improves the efficiency of image data usage. Furthermore, there is no need to store and manage CG production parameters for each system. In particular, a CG model previously produced using a low-speed CG production system can be used to perform rendering processing in the future using another high-speed CG production system. Therefore, the CGI accumulated with the old system! You can migrate to a faster system without losing your production know-how. Furthermore, with the speeding up of computers, excellent effects such as the ability to freely speed up the CG system can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the entire configuration of the rental system according to the embodiment of the present invention, FIG. 2 is a block diagram showing the entire configuration of the interface section of the embodiment, and FIG. , (B), and (C) are flowcharts showing specular reflection conversion instructions for explaining the operation of the embodiment, and FIG. 4 is a diagram showing an example of transmittance conversion. 1 ...System A, 2...System B, 3...Interface unit, 4...Information format conversion unit, 5...Shape design unit, 6...Shape design specification unit, 7...・Camera/light source/shape position information specification section, 8...
Texture/light source/mapping information specification unit, 10... System texture model reading device, 12... Shape data/shape position input device, 14... System B texture model reading storage device, 16... System B role image creation device, 18...rendering interface (I/F
) device, 20... first texture parameter reading storage section, 22.
... first mapping image reading storage section, 24 ... first light source parameter reading storage section, 26 ... second texture parameter reading storage section, 28 ... second mapping image reading storage section, 30... Second light source parameter reading storage section, 32... Texture parameter converting section, 34... Mapping image converting section, 36... Light source parameter converting section, 38... Camera information, camera position input Device. Figure 1 2 (System B) Figure 2 Figure 3 (A) Figure 3 (B) Figure 3<C)

Claims (1)

[Claims] (1) In a computer graphics system,
Object shape information produced by the first system, camera information,
Camera position information, light source position information, object shape position information,
An apparatus for rendering a computer graphics model consisting of texture information, light source information, mapping information, etc. in a second system having a different shading calculation model from the first system, the apparatus rendering the texture information of the first system. means for inputting light source information of the first system and converting it into texture information for the second system; means for inputting light source information of the first system and converting it into light source information for the second system; an interface unit including means for inputting mapping information of one system and converting it into mapping information for a second system, and absorbing differences in the shadow calculation model; A rendering device comprising: means for converting information read out in an information format different from the information format of the interface section into the information format of the interface section.