Apparatus and method for displaying three-dimensional polygons

• US 6,456,286 B1
• Filed: 11/19/1999
• Issued: 09/24/2002
• Est. Priority Date: 02/23/1999
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Arai, Masatoshi, Miyata, Ryosuke
• Primary Examiner(s): Zimmerman, Mark
• Assistant Examiner(s): ALEXANDER REINDOR, NAA OBOSHIE C
• Application Number:
  US09/443,140
• Time in Patent Office: 1,040 Days
• Field of Search: 345/419, 345/428, 345/423, 345/420
• US Class Current: 345/423
• CPC Class Codes: G06T 15/00 3D [Three Dimensional] image rendering

Abstract

A polygon rendering capability detecting part detects the rendering capability of the equipment used so as to calculate the total number of polygons N_ap that can be allocated in one frame. A visual quality determining part determines an average area S_p represented by one polygon on a display screen as visual quality, and an optimum polygon number calculating part calculates the optimum number of polygons N_p that can be allocated based on the size of a three-dimensional character projected on the display screen while maintaining the visual quality S_p constant. A polygon number adjusting part lowers the progressive polygon level of the three-dimensional character so that the number of polygons of the three-dimensional character is not less than the calculated optimum number of polygons and is the smallest number of polygons to which the number of polygons can be reduced. When the three-dimensional character moves and the Z value is changed, N_p is updated so that S_p becomes constant.

Claims

1. A three-dimensional polygon display apparatus using progressive polygon data for forming a polygon mesh of a three-dimensional character, comprising:

a visual quality determining part for determining visual quality, that is defined by an average area represented by one polygon on a display screen and indicates picture quality perceived by a user;

an optimum polygon number calculating part for calculating a number of polygons, that can be allocated to the three-dimensional character while maintaining the determined visual quality as a constant, as an optimum number of polygons; and

a polygon number adjusting part for adjusting a progressive polygon level so that a number of polygons of the three-dimensional character is not less than the calculated optimum number of polygons and is a smallest number of polygons to which the number of polygons can be reduced.

2. The three-dimensional polygon display apparatus according to claim 1, comprising a polygon rendering capability detecting part for detecting hardware processing capability that defines a total number of polygons N_ap that can be rendered in one frame of the three-dimensional polygon display apparatus.

3. The three-dimensional polygon display apparatus according to claim 2, wherein the visual quality determining part calculates the visual quality S_p using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, the total number of polygons N_ap that can be rendered in one frame, a distance Z between the three-dimensional character and a camera and ½

of an angle of view θ

from the camera to the display screen as parameters according to;

$\mathrm{Sp}={\left(\frac{w}{2<br><br>Z<br><br>\text{\hspace{1em}<br><br>}<br><br>\tan <br><br>\frac{\mathrm{\theta <br><br>}}{2}}\right)}^2<br><br>\mathrm{Sr}/\frac{\mathrm{Nap}}{2}=\frac{W^2<br><br>\mathrm{Sr}}{2<br><br>{\mathrm{NapZ}}^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}.$

4. The three-dimensional polygon display apparatus according to claim 3, wherein the optimum polygon number calculating part calculates the optimum number of polygons N_p using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, a distance Z between the three-dimensional character and a camera, ½

of an angle θ

view a from the camera to the display screen, and the visual quality S_p as parameters according to;

$\mathrm{Np}=\frac{w^2}{2<br><br>Z^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}<br><br>\frac{\mathrm{Sr}}{\mathrm{Sp}}.$

5. The three-dimensional polygon display apparatus according to claim 2, wherein the polygon rendering capability detecting part detects a polygon rendering capability based on a proportion of a capability that is allowed to render polygons to the hardware processing capability of the three-dimensional polygon display apparatus.

6. The three-dimensional polygon display apparatus according to claim 5, wherein the visual quality determining part calculates the visual quality S_p using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, the total number of polygons N_ap that can be rendered in one frame, a distance Z between the three-dimensional character and a camera, and ½

of an angle of view θ

from the camera to the display screen as parameters according to;

$\mathrm{Sp}={\left(\frac{w}{2<br><br>Z<br><br>\text{\hspace{1em}<br><br>}<br><br>\tan <br><br>\frac{\mathrm{\theta <br><br>}}{2}}\right)}^2<br><br>\mathrm{Sr}/\frac{\mathrm{Nap}}{2}=\frac{W^2<br><br>\mathrm{Sr}}{2<br><br>{\mathrm{NapZ}}^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}.$

7. The three-dimensional polygon display apparatus according to claim 6, wherein the optimum polygon number calculating part calculates the optimum number of polygons N_p using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, a distance Z between the three-dimensional character and a camera, ½

of a angle view θ

from the camera to the display screen, and the visual quality S_p as parameters according to;

$\mathrm{Np}=\frac{w^2}{2<br><br>Z^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}<br><br>\frac{\mathrm{Sr}}{\mathrm{Sp}}.$

8. The three-dimensional polygon display apparatus according to claim 1, wherein the polygon data of the three-dimensional character is progressive polygon data, and the polygon number adjusting part lowers the progressive polygon level until a number of polygons to be allocated to the three-dimensional character becomes a number of polygons nearest to the calculated optimum number of polygons N_p.

9. A method for displaying three-dimensional polygons using progressive polygon data for forming a polygon mesh of a three-dimensional character, comprising:

a visual quality determining step of determining visual quality, that is defined by an average area represented by one polygon on a display screen and indicates picture quality perceived by a user;

an optimum polygon number calculating step of calculating a number of polygons that can be allocated to the three-dimensional character while maintaining the determined visual quality as a constant, as an optimum number of polygons; and

a polygon number adjusting step of adjusting a progressive polygon level so that a number of polygons of the three-dimensional character is not less than the calculated optimum number of polygons and is a smallest number of polygons to which the number of polygons can be reduced.

10. The method for displaying three-dimensional polygons according to claim 9, comprising a polygon rendering capability detecting step of detecting hardware processing capability that defines a total number of polygons N_ap that can be rendered in one frame of a three-dimensional polygon display apparatus that executes the method.

11. The method of displaying three-dimensional polygons according to claim 10, wherein the visual quality determining step calculates the visual quality S_ap using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, the total number of polygons N_ap that can be rendered in one frame, a distance Z between the three-dimensional character and a camera, and ½

of an angle of view θ

from the camera to the display screen as parameters according to;

$\mathrm{Sp}={\left(\frac{w}{2<br><br>Z<br><br>\text{\hspace{1em}<br><br>}<br><br>\tan <br><br>\frac{\mathrm{\theta <br><br>}}{2}}\right)}^2<br><br>\mathrm{Sr}/\frac{\mathrm{Nap}}{2}=\frac{W^2<br><br>\mathrm{Sr}}{2<br><br>{\mathrm{NapZ}}^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}.$

12. The method for display three-dimensional polygons according to claim 11, wherein the optimum polygon number calculating step calculates the optimum number of polygons N_p using a unit length w (pixels) on a display screen, an area S_r of the three-dimensional character, a distance Z between the three-dimensional character and a camera, ½

of an angle of view θ

from the camera to the display screen, and the visual quality S_p as parameters according to;

$\mathrm{Np}=\frac{w^2}{2<br><br>Z^2<br><br>{\tan }^2<br><br>\frac{\mathrm{\theta <br><br>}}{2}}<br><br>\frac{\mathrm{Sr}}{\mathrm{Sp}}.$

13. The method for displaying three-dimensional polygons according to claim 9, wherein the polygon data of the three-dimensional character is progressive polygon data, and the polygon number adjusting step lowers the progressive polygon level until a number of polygons to be allocated to the three-dimensional character becomes a number of polygons nearest to the calculated optimum number of polygons N_p.

14. A computer-readable recording medium storing a program for realizing a three-dimensional polygon display apparatus using progressive polygon data for forming a polygon mesh of a three-dimensional character in accordance with display resolution, comprising:

a visual quality determining step of determining visual quality that is defined by an average area represented by one polygon on a display screen and indicates picture quality perceived by a user;

an optimum polygon number calculating step of calculating a number of polygons, that can be allocated to the three-dimensional character while maintaining the determined visual quality as a constant, as an optimum number of polygons; and

a polygon number adjusting step of adjusting a progressive polygon level so that a number of polygons of the three-dimensional character is not less than the calculated optimum number of polygons and is a smallest number of polygons to which the number of polygons can be reduced.