college/school/informatik/verkerhssimulation/media/materials/programs/DepthShadowmapNormalMapReceiverFp.glsl
2013-12-19 19:32:50 +01:00

85 lines
2.3 KiB
GLSL

uniform float inverseShadowmapSize;
uniform float fixedDepthBias;
uniform float gradientClamp;
uniform float gradientScaleBias;
uniform float shadowFuzzyWidth;
uniform vec4 lightColour;
uniform sampler2D shadowMap;
uniform sampler2D normalMap;
varying vec3 tangentLightDir;
// Expand a range-compressed vector
vec3 expand(vec3 v)
{
return (v - 0.5) * 2.0;
}
void main()
{
// get the new normal and diffuse values
vec3 normal = normalize(expand(texture2D(normalMap, gl_TexCoord[1].xy).xyz));
vec4 vertexColour = clamp(dot(normal, tangentLightDir),0.0,1.0) * lightColour;
vec4 shadowUV = gl_TexCoord[0];
// point on shadowmap
#if LINEAR_RANGE
shadowUV.xy = shadowUV.xy / shadowUV.w;
#else
shadowUV = shadowUV / shadowUV.w;
#endif
float centerdepth = texture2D(shadowMap, shadowUV.xy).x;
// gradient calculation
float pixeloffset = inverseShadowmapSize;
vec4 depths = vec4(
texture2D(shadowMap, shadowUV.xy + vec2(-pixeloffset, 0)).x,
texture2D(shadowMap, shadowUV.xy + vec2(+pixeloffset, 0)).x,
texture2D(shadowMap, shadowUV.xy + vec2(0, -pixeloffset)).x,
texture2D(shadowMap, shadowUV.xy + vec2(0, +pixeloffset)).x);
vec2 differences = abs( depths.yw - depths.xz );
float gradient = min(gradientClamp, max(differences.x, differences.y));
float gradientFactor = gradient * gradientScaleBias;
// visibility function
float depthAdjust = gradientFactor + (fixedDepthBias * centerdepth);
float finalCenterDepth = centerdepth + depthAdjust;
// shadowUV.z contains lightspace position of current object
#if FUZZY_TEST
// fuzzy test - introduces some ghosting in result and doesn't appear to be needed?
//float visibility = saturate(1 + delta_z / (gradient * shadowFuzzyWidth));
float visibility = saturate(1 + (finalCenterDepth - shadowUV.z) * shadowFuzzyWidth * shadowUV.w);
gl_FragColor = vertexColour * visibility;
#else
// hard test
#if PCF
// use depths from prev, calculate diff
depths += depthAdjust;
float final = (finalCenterDepth > shadowUV.z) ? 1.0 : 0.0;
final += (depths.x > shadowUV.z) ? 1.0 : 0.0;
final += (depths.y > shadowUV.z) ? 1.0 : 0.0;
final += (depths.z > shadowUV.z) ? 1.0 : 0.0;
final += (depths.w > shadowUV.z) ? 1.0 : 0.0;
final *= 0.2;
gl_FragColor = vec4(vertexColour.xyz * final, 1);
#else
gl_FragColor = (finalCenterDepth > shadowUV.z) ? vertexColour : vec4(0,0,0,1);
#endif
#endif
}