SLIDE 1
Graphics Pipeline
(Slides courtesy of Tamar Shinar)
Graphics Pipeline
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Graphics Pipeline (Slides courtesy of Tamar Shinar) Graphics - - PowerPoint PPT Presentation
Graphics Pipeline (Slides courtesy of Tamar Shinar) Graphics - - PowerPoint PPT Presentation
Graphics Pipeline (Slides courtesy of Tamar Shinar) Graphics Pipeline ff Transform ff Modelview Transformation Object World Eye coordinates coordinates coordinates Model View Project ff Projection: map 3D scene to 2D image
SLIDE 2
SLIDE 3
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Transform
SLIDE 4
Eye coordinates
“Modelview” Transformation
Object coordinates World coordinates
View Model
SLIDE 5
ff
Project
SLIDE 6
OpenGL Super Bible, 5th Ed.
Projection: map 3D scene to 2D image
SLIDE 7
Orthographic projection
vector.tutsplus.com
SLIDE 8
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OpenGL Orthogonal Viewing
glOrtho(left,right,bottom,top,near,far)
View volume for an orthographic projection
SLIDE 9
Perspective projection
www.artyfactory.com
SLIDE 10
10
OpenGL Perspective Viewing
glFrustum(xmin,xmax,ymin,ymax,near,far)
View volume (frustrum) for a perspective projection
SLIDE 11
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Clip
SLIDE 12
Clip against view volume
SLIDE 13
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Hidden Surface Removal
SLIDE 14
Occlusion
“painter’s algorithm” draw primitives in back-to-front order
[Wikimedia Commons]
SLIDE 15
Occlusion
“painter’s algorithm” draw primitives in back-to- front order problem: triangle intersection
SLIDE 16
Occlusion
“painter’s algorithm” draw primitives in back-to- front order problem:
- cclusion cycle
SLIDE 17
Use a z-buffer for hidden surface removal
test depth on a pixel by pixel basis
with z-buffer without z-buffer
red drawn last
SLIDE 18
Use a z-buffer for hidden surface removal
at each pixel, record distance to the closest
- bject that has been drawn in a depth buffer
with z-buffer without z-buffer
SLIDE 19
Use a z-buffer for hidden surface removal
http://www.beyond3d.com/content/articles/41/
SLIDE 20
Backface culling: another way to eliminate hidden geometry
SLIDE 21
Hidden Surface Removal in OpenGL
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); glEnable(GL_DEPTH_TEST); glEnable(GL_CULL_FACE);