| // Fragment shader for 2D texture with shadow attenuation | |
| // Brian Paul | |
| uniform sampler2D tex2d; | |
| uniform vec3 lightPos; | |
| void main() | |
| { | |
| // XXX should compute this from lightPos | |
| vec2 shadowCenter = vec2(-0.25, -0.25); | |
| // d = distance from center | |
| float d = distance(gl_TexCoord[0].xy, shadowCenter); | |
| // attenuate and clamp | |
| d = clamp(d * d * d, 0.0, 2.0); | |
| // modulate texture by d for shadow effect | |
| gl_FragColor = d * texture2D(tex2d, gl_TexCoord[0].xy, 0.0); | |
| } |