TWI482998B - Illumination environment simulation system and method - Google Patents

Description

Lighting environment analogy system and method

The invention relates to a computer aided design system and method, in particular to an illumination environment analogy system and method applied in the field of three-dimensional measurement.

In the three-dimensional measurement system, if the object to be measured is not subjected to illumination processing, the object to be measured cannot display the stereoscopic effect, and only the planar effect (as shown in FIG. 11) can be displayed, resulting in the inability to recognize the detailed features of the object. However, the conventional auxiliary illumination system cannot reflect the characteristics of the light source attenuating with distance, and thus the stereoscopic effect displayed by the object to be tested is not real enough.

In view of the above, it is necessary to provide a lighting environment analogy system and method, which can simulate the stereoscopic effect of the object to be tested more realistically than the illumination effect of the object to be tested.

An illumination environment analog system is applied to an electronic device. The system includes a triangular meshing module, a lighting environment configuration module, a computing module, and a display module. The triangular meshing module is configured to read a three-dimensional object from a storage device connected to the electronic device, and perform a triangular meshing process on the three-dimensional object. The lighting environment configuration module is configured to configure a lighting environment for the triangular meshed processed three-dimensional object, including determining an illumination range, a light source position, a light direction, and a light source intensity parameter. The calculation module is used to determine the actual shape of each triangle according to the initial color of the three-dimensional object, the angle between the illumination ray along the illumination direction and the surface normal vector of each triangle on the three-dimensional object, and the distance between each triangle and the position of the light source. Display color. The display module is configured to project the three-dimensional object to the display device connected to the electronic device according to the coordinates of the triangles on the three-dimensional object and the actual display color.

An illumination environment analogy method applied to an electronic device. The method comprises: (A) a triangular meshing step: reading a three-dimensional object from a storage device connected to the electronic device, and performing a triangular meshing process on the three-dimensional object; (B) a lighting environment configuration step: for the triangle The gridded processed 3D object configures the lighting environment, including determining the illumination range, the light source position, the illumination direction, and the light source intensity parameter; (C) the triangle display color calculation step: according to the initial color of the three-dimensional object, the illumination ray along the illumination direction The angle between the surface normal vectors of the triangles on the three-dimensional object and the distance between each triangle and the position of the light source determine the actual display color of each triangle; and (D) the display step: projecting the three-dimensional object according to the coordinates of the triangles on the three-dimensional object and the actual display color To the display device output connected to the electronic device.

Compared with the prior art, the lighting environment analogy system and method provided by the present invention can simulate the stereoscopic effect of the object to be tested more realistically than the illumination effect of the object to be tested.

100‧‧‧Electronic devices

10‧‧‧Lighting environment analogy system

11‧‧‧Triangular grid module

13‧‧‧Light environment configuration module

15‧‧‧Computation Module

17‧‧‧Display module

20‧‧‧Storage equipment

30‧‧‧ Processor

40‧‧‧Display equipment

1 is a functional block diagram of a preferred embodiment of the illumination environment analog system of the present invention.

2 is a flow chart of a preferred embodiment of the illumination environment analogy method of the present invention.

FIG. 3 is a specific flowchart of step S210 in FIG. 2.

FIG. 4 is a specific flowchart of step S220 in FIG. 2.

FIG. 5 is a specific flowchart of step S230 in FIG. 2.

FIG. 6 is a specific flowchart of step S240 in FIG. 2.

7 and 8 are schematic views of triangulation of a three-dimensional object.

Figure 9 is a schematic diagram of configuring a lighting environment for a three-dimensional object.

Fig. 10 is a schematic diagram showing the division of the illumination depth.

FIG. 11 is a schematic diagram showing the planar effect of the object to be measured in the no-light environment in the three-dimensional measurement.

FIG. 12 is a schematic diagram showing the stereoscopic effect of the object to be measured displayed in the analog lighting environment of the present invention.

As shown in FIG. 1, it is a functional module diagram of a preferred embodiment of the illumination environment analog system 10 of the present invention. The lighting environment analog system 10 is installed and operates on the electronic device 100. The electronic device 100 further includes a storage device 20, a processor 30, and a display device 40. The electronic device 100 can be a computer or any other device having data processing functions.

The storage device 20 is configured to store computerized code of the lighting environment analog system 10. The storage device 20 may be a memory built in the electronic device 100 or a memory external to the electronic device 100.

The processor 30 executes the computerized code of the lighting environment analog system 10, and provides an analog lighting environment for the three-dimensional object to be measured, and obtains a more realistic stereoscopic display effect of the three-dimensional object in an analog lighting environment.

The display device 40 is configured to display a stereoscopic display effect of the three-dimensional object in an analog lighting environment.

The lighting environment analog system 10 includes a triangular meshing module 11, a lighting environment configuration module 13, a computing module 15, and a display module 17.

The triangular meshing module 11 is used for triangulating the three-dimensional object (specifically See below for the description of Figure 3).

The lighting environment configuration module 13 is configured to configure a lighting environment for the triangular meshed processed three-dimensional object, including determining an illumination range, a light source position, a light direction, and a light source intensity parameter (for details, please refer to the description of FIG. 4 below) .

The calculation module 15 is configured to determine the actual display color of each triangle according to the initial color of the three-dimensional object, the angle between the illumination ray in the illumination direction and the surface normal vector of each triangle on the three-dimensional object, and the distance between each triangle and the position of the light source. See description below with respect to Figure 5).

The display module 17 is configured to project a three-dimensional object to the display device 40 according to the coordinates of the triangles on the three-dimensional object and the actual display color (for details, please refer to the description of FIG. 6 below).

2 is a flow chart of a preferred embodiment of the illumination environment analogy method of the present invention.

In step S210, the triangular meshing module 11 performs a triangular meshing process on the three-dimensional object (refer to FIG. 3 for specific introduction).

In step S220, the illumination environment configuration module 13 configures the illumination environment for the three-dimensional object after the triangle meshing process, including determining the illumination range, the light source position, the illumination direction, and the light source intensity parameter (refer to FIG. 4 for specific introduction).

Step S230, the calculation module 15 determines the actual display color of each triangle according to the initial color of the three-dimensional object, the angle between the illumination ray in the illumination direction and the surface normal vector of each triangle on the three-dimensional object, and the distance between each triangle and the position of the light source (specific introduction See Figure 5).

Step S240, the display module 17 according to the coordinates of the triangles on the three-dimensional object and the actual display The color is projected onto the display device 40 output (see Figure 6 for details).

As shown in FIG. 3, it is a specific flowchart of step S210 in FIG. 2.

In step S310, the triangular meshing module 11 reads a three-dimensional object model from the storage device 20.

In step S320, the triangular meshing module 11 checks whether the three-dimensional object model is composed of triangular patches. If it is composed of triangular patches, the flow directly proceeds to step S380, otherwise the flow proceeds to step S330.

In step S330, the triangular meshing module 11 converts the three-dimensional object model into a B-spline surface, and obtains a closed boundary line of the B-spline surface in the UV parameter plane, and the U-line and the V-line are performed on the closed boundary line. Points, get a few small squares (as shown in Figure 7).

In step S340, the triangular meshing module 11 forms two triangles in a counterclockwise order of the four vertices of the small square having no intersection with the closed boundary line. For example, if the four vertices P, Q, I, and O of the small square box 4 shown in FIG. 8 fall within the closed boundary line, the triangular meshing module 11 follows the vertices P, Q, I, and O. The two triangles OQP and OIQ are formed by connecting counterclockwise.

Step S350, for a small square having an intersection with the closed boundary line, the triangular meshing module 11 falls into the vertices of the small square lattice, the intersection of the small square and the closed boundary curve, and the closed boundary. The boundary point on the line is added to the queue Q composed of 2D points. For example, as shown in FIG. 8 , the small square box 1 has a boundary point M on a closed boundary line, an intersection point E and F of a small square box 1 and a closed boundary curve; and a small square box 2 has a vertex D falling into a closed boundary curve. Inside, the intersection of the small square box2 and the closed boundary curve, F, C, and G, the triangular meshing module 11 adds the points M, E, F, C, D, and G to the array Q composed of 2D points.

In step S360, the triangular meshing module 11 reads the first point p1 of the array Q composed of 2D points and the point p2 closest to the point p1, P1 and p2 form one side of the triangle A, and the third point p3 of the triangle The search principle is that the inner angle corresponding to the edge p1p2 is the largest among the inner corners of the triangle A and the circumscribed circle of the triangle A has no point in the array Q, so that the triangle A is close to the equilateral triangle.

In step S370, the triangular meshing module 11 searches for the vertices of other triangles in the queue Q according to the above-mentioned search principle, and obtains all the triangles on the three-dimensional object model.

In step S380, the triangular meshing module 11 outputs a queue T composed of all triangles on the three-dimensional object model.

As shown in FIG. 4, it is a specific flowchart of step S220 in FIG. 2.

In step S410, the illumination environment configuration module 13 determines the illumination range according to the coordinates of the maximum space bounding box of the three-dimensional object model after the triangular meshing process. For example, assuming that the maximum space bounding box of the three-dimensional object model is the rectangular parallelepiped shown in FIG. 9, the illumination range is the rectangular parallelepiped region.

In step S420, the illumination environment configuration module 13 determines the coordinates of the position of the light source according to the coordinates of the center point of the upper surface of the maximum space bounding box. For example, assuming that the coordinates of the center point of the upper surface of the rectangular parallelepiped shown in FIG. 9 are (x1, y1, z1), the coordinates of the position of the light source are (x1, y1, z1).

In step S430, the illumination environment configuration module 13 determines an illumination cone according to the position of the light source and the illumination range, and determines that the rotation axis of the illumination cone is the illumination ray S, the illumination direction is the same as the illumination ray S, and the height of the rotation axis is the illumination depth. For example, as shown in Figure 9. The illumination environment configuration module 13 takes the position of the light source as a vertex, and draws the illumination cone with the distance between the upper and lower surfaces of the maximum space bounding box (ie, the rectangular parallelepiped) of the three-dimensional object model as the height of the rotation axis.

Step S440, the illumination environment configuration module 13 divides the illumination depth into n illumination segments to obtain a sequence of points, calculates the distance of each point to the apex of the illumination ray to obtain the attenuation coefficient of each point, and determines the intensity of the light source in the column P, P. Each element includes a distance from a point in each sequence of points to the apex of the illumination ray and an attenuation coefficient at that point, wherein the attenuation coefficient of each point is the ratio of the distance from the point to the apex of the illumination ray S to the depth of illumination. As shown in FIG. 10, it is assumed that the line segment G1G5 is the illumination depth (G1 is the apex of the illumination ray S), and is divided into four illumination segments by the illumination environment configuration module 13 to obtain the point sequence G1, G2, G3, G4, G5. The attenuation coefficient of G1 is 0, the attenuation coefficient of G2 is |G1G2|/|G1G5|, the attenuation coefficient of G3 is |G1G3|/|G1G5|, the attenuation coefficient of G4 is |G1G4|/|G1G5|, and the attenuation coefficient of G5 is | G1G5|/|G1G5|=1.

As shown in FIG. 5, it is a specific flowchart of step S230 in FIG. 2.

In step S510, the calculation module 15 calculates the surface normal vectors of the triangles according to the coordinates of the vertices of the triangles, and obtains the array N of the surface normal vectors of all the triangles of the three-dimensional object model. For example, assuming that the vertex of the triangle A is v0, v1, v2, the face normal vector of the triangle A is normal=cross((v1-v0), (v2-v0)).

Step S520, the calculation module 15 reads the initial RGB color value of the three-dimensional object model, and divides the initial RGB color value into 90 RGB color value intervals to obtain a color array composed of RGB color values from light to dark gradients. L. For example, assuming that the initial color of the three-dimensional object model is yellow, the calculation module 15 divides the RGB value of the yellow into 90 RGB color value intervals to obtain 90 sets of RGB color values from the bright yellow to the dark yellow gradient. The reason is divided into 90 color intervals, which are based on an object (such as the three-dimensional object) and light. The principle that the object is invisible when the angle of the vector of the source exceeds 90 degrees.

In step S530, the calculation module 15 calculates a vector angle between the illumination ray S and the surface normal vector of each triangle, and determines a color interval Ith corresponding to each vector angle. For example, assuming that the angle between the illumination ray S and the triangle A is 30.5 degrees, the vector angle corresponds to the 30th color interval.

Step S540, the calculation module 15 calculates the distance between the illumination ray S and the center point of each triangle, and obtains the attenuation coefficient k of each triangle according to the correspondence between the distance and the attenuation coefficient in the intensity of the light source, according to the integer part of Ith*k. The actual display color of each triangle obtained from the corresponding color interval. For example, assuming that the distance between the illumination ray S and the center point of the triangle A is 8.1 cm and the illumination depth is 10 cm, the attenuation coefficient of the center point of the triangle A is 0.81, and the actual color interval of the triangle A is int (30*0.81)=24. The actual color value of the triangle A is the RGB value of the 24th color interval.

In step S550, the calculation module 15 outputs a color array C composed of the actual display colors of all the triangles on the three-dimensional object model.

As shown in FIG. 6, it is a specific flowchart of step S240 in FIG. 2.

In step S610, the display module 17 determines the display range of the display plane according to the resolution of the display device 40. For example, if the resolution of the display device 40 is 1024*768, the display module 17 determines that the display range of the display plane is P1 (0, 0), P2 (1023, 0), P3 (1023, 767), P4 (0). , 767) A rectangular area determined by four primitive points.

In step S620, the display module 17 projects the triangles in the triangle array T onto the display plane to obtain the 2D vertex coordinates of the plane triangle corresponding to each triangle on the three-dimensional object model. As shown in FIG. 9, the display module 17 projects the triangle A in the triangle array T A plane triangle A2 is obtained to the display plane. If there is a flat triangle beyond the display range of the display plane, the display module 17 reduces the 2D vertex coordinates of each planar triangle to the display range of the display plane by the same ratio (for example, 90%).

In step S630, the display module 17 displays all the planar triangles on the display device 40 according to the actual display color of each triangle and the 2D vertex coordinates. As shown in FIG. 12, it is a schematic diagram of a stereoscopic effect displayed by an object to be measured in an analog lighting environment of the present invention.

The above is only the preferred embodiment of the present invention, and has been used in a wide range of applications. Any other equivalent changes or modifications which are not departing from the spirit of the present invention should be included in the following claims. Inside.

100‧‧‧Electronic devices

10‧‧‧Lighting environment analogy system

11‧‧‧Triangular grid module

13‧‧‧Light environment configuration module

15‧‧‧Computation Module

17‧‧‧Display module

20‧‧‧Storage equipment

30‧‧‧ Processor

40‧‧‧Display equipment

Claims (9)

An illumination environment analogy method is applied to an electronic device, the method comprising: a triangular meshing step: reading a three-dimensional object model from a storage device connected to the electronic device, and performing a triangular meshing process on the three-dimensional object model; a configuration step of: configuring a lighting environment for the triangular meshed processed three-dimensional object model, comprising: determining an illumination range according to a coordinate of a maximum space bounding box of the three-dimensional object model after the triangular meshing process; The coordinates of the center point of the upper surface of the box determine the coordinates of the position of the light source; determine an illumination cone according to the position of the light source and the illumination range, and determine that the rotation axis of the illumination cone is the illumination ray S, the direction of the illumination ray S is the illumination direction, and the rotation axis The height is the illumination depth; and the illumination depth is divided into n illumination segments to obtain a sequence of points. The distance from each point to the apex of the illumination ray is calculated to obtain the attenuation coefficient of each point, and the intensity of the source is determined. P, each element in P includes The distance from a point in each sequence of points to the apex of the illumination ray and the attenuation coefficient at that point, where each point The attenuation coefficient is the ratio of the distance from the point to the apex of the illumination ray and the illumination depth; the triangle display color calculation step: according to the initial color of the three-dimensional object model, the illumination ray along the illumination direction and the surface normal vector of each triangle on the three-dimensional object model The angle of the angle and the distance between each triangle and the position of the light source determine the actual display color of each triangle; and the display step: projecting the three-dimensional object model to the output of the display device connected to the electronic device according to the coordinates of each triangle on the three-dimensional object model and the actual display color . The illumination environment analogy method of claim 1, wherein the triangular meshing step comprises: checking whether the three-dimensional object model is composed of triangular patches, and if it is composed of triangular patches, the flow is directly Enter the step of the triangle array T of all triangles on the output 3D object model If the three-dimensional object model is not composed of triangular patches, the three-dimensional object model is converted into a B-spline surface, and a closed boundary line of the B-spline surface in the UV parameter plane is obtained, and the closed boundary line is U. The straight line and the V line are equally divided to obtain a plurality of small squares; the four vertices of the small square having no intersection with the closed boundary line are formed into two triangles in a counterclockwise order; for small squares having intersections with the closed boundary line Adding the vertex of the small square into the closed boundary curve, the intersection of the small square and the closed boundary curve, and the boundary point on the closed boundary line are added to the two-dimensional point array Q composed of two-dimensional points; The first point p1 in the point array and the point p2 closest to the point p1, p1, p2 form one side of the triangle A, and the third point p3 of the triangle A is searched by the inner angle of the side p1p2 corresponding to the inner angle of the triangle A The maximum and the circumscribed circle of the triangle A do not have a point in the two-dimensional point QQ, so that the triangle A is close to the equilateral triangle; according to the above search principle, the vertices of other triangles are searched in the two-dimensional point , column to obtain a three-dimensional object model. Up Triangular; triangle and all triangles on the three-dimensional object model consisting of the output queue T. The illumination environment analogy method of claim 2, wherein the triangle display color calculation step comprises: calculating a surface normal vector of each triangle according to each triangle vertex coordinate, and obtaining a surface normal vector composition of all triangles of the three-dimensional object model. The initial RGB color value of the three-dimensional object model is read, and the initial RGB color value is equally divided into 90 RGB color value intervals to obtain a color 伫 column L composed of RGB color values from light to dark gradation; Calculate the angle between the illumination ray S and the surface normal vector of each triangle, determine the color interval Ith corresponding to each vector angle; calculate the distance between the illumination ray S and the center point of each triangle, and select the distance in the P according to the intensity of the light source. Corresponding relationship with the attenuation coefficient obtains the attenuation coefficient k of each triangle, and the actual display color of each triangle is obtained according to the color interval corresponding to the integer part of Ith*k; and the color of the actual display color of all triangles on the output three-dimensional object model伫Column C. The illumination environment analogy method of claim 3, wherein the displaying step comprises: determining a display range of the display plane according to the resolution of the display device; projecting each triangle in the triangle array T to The display plane obtains two-dimensional vertex coordinates of the planar triangle corresponding to each triangle on the three-dimensional object model; and all the planar triangles displayed on the display device according to the actual display color of each triangle and the two-dimensional vertex coordinates. The illumination environment analogy method of claim 4, wherein if the planar triangle is beyond the display range of the display plane, the two-dimensional vertex coordinates of each planar triangle are reduced to the display range of the display plane by the same scale. An illumination environment analog system is applied to an electronic device, the system comprising: a triangular meshing module, configured to read a three-dimensional object model from a storage device connected to the electronic device, and perform a triangular meshing process on the three-dimensional object model a lighting environment configuration module, configured to configure a lighting environment for the triangular meshing processed three-dimensional object model, comprising: determining an illumination range according to a coordinate of a maximum space bounding box of the three-dimensional object model after the triangular meshing process; Determining a coordinate of the position of the light source according to the coordinates of the center point of the upper surface of the maximum space bounding box; determining an illumination cone according to the position of the light source and the illumination range, determining that the rotation axis of the illumination cone is the illumination ray S, and the direction of the illumination ray S is the illumination Direction, the height of the rotation axis is the illumination depth; and determining an illumination cone according to the position of the light source and the illumination range, determining that the rotation axis of the illumination cone is the illumination ray S, the direction of the illumination ray S is the illumination direction, and the height of the rotation axis For the light depth; and divide the light depth into n illumination segments to get the point sequence, calculate each Light rays from a point S to the apex of each point to obtain the attenuation coefficient, Determining the intensity of the light source 伫 column P, each element in P includes the distance from a point in each sequence of points to the apex of the illumination ray and the attenuation coefficient of the point, wherein the attenuation coefficient of each point is the distance from the point to the apex of the illumination ray S and The ratio of the illumination depth; the calculation module is configured to determine the angle of each triangle according to the initial color of the three-dimensional object model, the angle between the illumination ray along the illumination direction and the surface normal vector of each triangle on the three-dimensional object model, and the distance between each triangle and the position of the light source The actual display color; and the display module is configured to project the three-dimensional object model to the display device connected to the electronic device according to the coordinates of the triangles on the three-dimensional object model and the actual display color. The illumination environment analogy system of claim 6, wherein the triangular meshing process comprises: checking whether the three-dimensional object model is composed of triangular patches, and if it is composed of triangular patches, the flow is directly Entering the step of outputting a triangular array T of all triangles on the three-dimensional object model; if the three-dimensional object model is not composed of triangular patches, converting the three-dimensional object model into a B-spline surface, obtaining a B-spline surface in the UV a closed boundary line in the parameter plane, the U-line and the V-line are equally divided into the closed boundary line to obtain a plurality of small squares; the four vertices of the small square having no intersection with the closed boundary line are formed in a counterclockwise order Two triangles; for small squares that have intersections with closed boundary lines, the vertices that fall into the closed boundary curve in the vertices of the small square, the intersection of the small square and the closed boundary curve, and the boundary points on the closed boundary line are added to The two-dimensional point 伫 column Q composed of dimensional points; the first point p1 in the two-dimensional point 伫 column and the point p2 closest to the point p1, p1, p2 form one side of the triangle A, and the triangle A Find the edge point p3 principle is p1p2 corresponding interior angle at the inner corner of the triangle A two-dimensional point in the queue does not point Q columns and triangular circumcircle A of the maximum, so that the triangle is close to an equilateral triangle A; According to the above search principle, the vertices of other triangles are searched in the two-dimensional point , column to obtain all the triangles on the three-dimensional object model; and the triangular 伫 column T composed of all the triangles on the three-dimensional object model is output. The illumination environment analogy system of claim 7, wherein the determining the actual display color of each triangle comprises: calculating a surface normal vector of each triangle according to the coordinates of each triangle vertex, and obtaining a surface method of all triangles of the three-dimensional object model. The vector consists of the array N; the initial RGB color value of the three-dimensional object model is read, and the initial RGB color value is equally divided into 90 RGB color value intervals to obtain a color array consisting of RGB color values from light to dark gradients. L; calculating the angle between the illumination ray S and the surface normal vector of each triangle, determining the color interval Ith corresponding to each vector angle; calculating the distance between the illumination ray S and the center point of each triangle, according to the intensity of the light source, the distance between the P and the distance Corresponding relationship of attenuation coefficients obtains the attenuation coefficient k of each triangle, and the actual display color of each triangle is obtained according to the color interval corresponding to the integer part of Ith*k; and the color display of the actual display color of all triangles on the output three-dimensional object model C. The illumination environment analogy system of claim 8, wherein the projecting the three-dimensional object model to the display device output connected to the electronic device comprises: determining the display of the display plane according to the resolution of the display device a range; a triangle of the triangle 伫 column T is projected onto the display plane to obtain a two-dimensional vertex coordinate of the plane triangle corresponding to each triangle on the three-dimensional object model; and the actual display color and the two-dimensional vertex coordinates of the respective triangles are displayed on the display device Show all the resulting planar triangles.