Computer Graphics 2021

lab11-GeometryPositionNormal

ShadedGeometry-PerVertexLighting

lab11-GeometryPositionNormalPerVertexLighting
http://en.wikibooks.org/wiki/GLSL_Programming/GLUT/Diffuse_Reflection
http://en.wikibooks.org/wiki/GLSL_Programming/GLUT/Specular_Highlights

ShadedGeometry-PerPixelLighting

lab11-GeometryPositionNormalPerPixelLighting
http://en.wikibooks.org/wiki/GLSL_Programming/GLUT/Smooth_Specular_Highlights 

ShadedGeometry with Multiple Lights & Material

• Directional Light
• Point Light
• Spot Light (‘l’ & ‘k’-key to move a spot light position)

lab11-GeometryPositionNormalMultipleLights3 (SimpleCar, SimpleSolar, SimpleRobot, SimpleMobile, SimpleCube3d, SimpleTree)

ShadedTeapotCylinderSphere (with moving light source)

ShadedTeapot (with different materials)

 

Ambient/Diffuse/Specular (From left to right: diffuse; ambient; diffuse + ambient; diffuse+ambient+specular) from lighthouse3d.com

Light sources (From left to right: directional; point; and spotlights) from lighthouse3d.com

lab10

lab10-GeometryPositionColorOrthoPerspectiveCamera-src

 

Z-fighting, also called stitching, is a phenomenon in 3D rendering that occurs when two or more primitives have similar values in the z-buffer. This problem is usually caused by limited sub-pixel precision and floating point and fixed point round-off errors. https://en.wikipedia.org/wiki/Z-fighting

 

There is very high precision at the near plane, but very little precision at the far plane. If the range [-n, -f] is getting larger, it causes a depth precision problem (z-fighting); a small change of z_e around the far plane does not affect on z_n value. The distance between n and f should be short as possible to minimize the depth buffer precision problem.

http://www.songho.ca/opengl/gl_projectionmatrix.html