armory/Shaders/std/ssrs.glsl
2020-05-11 09:03:13 +02:00

37 lines
970 B
GLSL

#ifndef _SSRS_GLSL_
#define _SSRS_GLSL_
#include "std/gbuffer.glsl"
uniform mat4 VP;
vec2 getProjectedCoord(vec3 hitCoord) {
vec4 projectedCoord = VP * vec4(hitCoord, 1.0);
projectedCoord.xy /= projectedCoord.w;
projectedCoord.xy = projectedCoord.xy * 0.5 + 0.5;
#if defined(HLSL) || defined(METAL)
projectedCoord.y = 1.0 - projectedCoord.y;
#endif
return projectedCoord.xy;
}
float getDeltaDepth(vec3 hitCoord, sampler2D gbufferD, mat4 invVP, vec3 eye) {
vec2 texCoord = getProjectedCoord(hitCoord);
float depth = textureLod(gbufferD, texCoord, 0.0).r * 2.0 - 1.0;
vec3 wpos = getPos2(invVP, depth, texCoord);
float d1 = length(eye - wpos);
float d2 = length(eye - hitCoord);
return d1 - d2;
}
float traceShadowSS(vec3 dir, vec3 hitCoord, sampler2D gbufferD, mat4 invVP, vec3 eye) {
dir *= ssrsRayStep;
for (int i = 0; i < 4; i++) {
hitCoord += dir;
if (getDeltaDepth(hitCoord, gbufferD, invVP, eye) > 0.0) return 1.0;
}
return 0.0;
}
#endif