three-d 0.19.0

2D/3D renderer - makes it simple to draw stuff across platforms (including web)
Documentation 
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#define PI 3.1415926

// clamping to 0 - 1 range
float saturate(in float value)
{
    return clamp(value, 0.0, 1.0);
}

vec3 world_pos_from_depth(mat4 viewProjectionInverse, float depth, vec2 uv) {
    vec4 clipSpacePosition = vec4(uv * 2.0 - 1.0, depth * 2.0 - 1.0, 1.0);
    vec4 position = viewProjectionInverse * clipSpacePosition;
    return position.xyz / position.w;
}

// http://holger.dammertz.org/stuff/notes_HammersleyOnHemisphere.html
// efficient VanDerCorpus calculation.
float RadicalInverse_VdC(uint bits) 
{
     bits = (bits << 16u) | (bits >> 16u);
     bits = ((bits & 0x55555555u) << 1u) | ((bits & 0xAAAAAAAAu) >> 1u);
     bits = ((bits & 0x33333333u) << 2u) | ((bits & 0xCCCCCCCCu) >> 2u);
     bits = ((bits & 0x0F0F0F0Fu) << 4u) | ((bits & 0xF0F0F0F0u) >> 4u);
     bits = ((bits & 0x00FF00FFu) << 8u) | ((bits & 0xFF00FF00u) >> 8u);
     return float(bits) * 2.3283064365386963e-10; // / 0x100000000
}

vec2 Hammersley(uint i, uint N)
{
	return vec2(float(i)/float(N), RadicalInverse_VdC(i));
}