VoxelEngine/res/shaders/lib/shadows.glsl

34 lines
936 B
GLSL

#ifndef SHADOWS_GLSL_
#define SHADOWS_GLSL_
float calc_shadow() {
float shadow = 1.0;
if (u_enableShadows) {
vec4 mpos = u_shadowsMatrix * vec4(a_modelpos.xyz + a_realnormal * 0.08, 1.0);
vec3 projCoords = mpos.xyz / mpos.w;
projCoords = projCoords * 0.5 + 0.5;
projCoords.z -= 0.0001;
shadow = 0.0;
if (dot(a_realnormal, u_sunDir) < 0.0) {
const vec3 offsets[4] = vec3[4](
vec3(0.5, 0.5, 0.0),
vec3(-0.5, 0.5, 0.0),
vec3(0.5, -0.5, 0.0),
vec3(-0.5, -0.5, 0.0)
);
for (int i = 0; i < 4; i++) {
shadow += texture(u_shadows, projCoords.xyz + offsets[i] / u_shadowsRes);
}
shadow /= 4;
shadow = shadow * 0.5 + 0.5;
} else {
shadow = 0.5;
}
}
return shadow;
}
#endif // SHADOWS_GLSL_