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fgdata/Shaders/shadows-include.vert
Fernando García Liñán 21a6e20701 Tweak shadow offset parameters and cascade ranges
This should hopefully fix some shadow acne edge cases.
2021-01-05 11:24:19 +01:00

45 lines
1.4 KiB
GLSL

#version 120
uniform bool shadows_enabled;
uniform mat4 fg_LightMatrix_csm0;
uniform mat4 fg_LightMatrix_csm1;
uniform mat4 fg_LightMatrix_csm2;
uniform mat4 fg_LightMatrix_csm3;
varying vec4 lightSpacePos[4];
const float NORMAL_OFFSET_SCALES[4] = float[4](0.0, 0.1, 0.3, 1.0);
void setupShadows(vec4 eyeSpacePos)
{
if (!shadows_enabled)
return;
vec3 normal = gl_NormalMatrix * gl_Normal;
vec3 toLight = normalize(gl_LightSource[0].position.xyz);
float costheta = dot(normal, toLight);
float slopeScale = clamp(1.0 - costheta, 0.0, 1.0);
vec4 offsetPos[4];
for (int i = 0; i < 4; i++) {
float normalOffset = NORMAL_OFFSET_SCALES[i] * slopeScale;
offsetPos[i] = eyeSpacePos + vec4(normal * normalOffset, 0.0);
}
vec4 offsetPosLightSpace[4];
offsetPosLightSpace[0] = fg_LightMatrix_csm0 * offsetPos[0];
offsetPosLightSpace[1] = fg_LightMatrix_csm1 * offsetPos[1];
offsetPosLightSpace[2] = fg_LightMatrix_csm2 * offsetPos[2];
offsetPosLightSpace[3] = fg_LightMatrix_csm3 * offsetPos[3];
lightSpacePos[0] = fg_LightMatrix_csm0 * eyeSpacePos;
lightSpacePos[1] = fg_LightMatrix_csm1 * eyeSpacePos;
lightSpacePos[2] = fg_LightMatrix_csm2 * eyeSpacePos;
lightSpacePos[3] = fg_LightMatrix_csm3 * eyeSpacePos;
// Offset only in UV space
for (int i = 0; i < 4; i++)
lightSpacePos[i].xy = offsetPosLightSpace[i].xy;
}