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@LVutner
Last active September 29, 2023 15:22
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LabPBR unpacking template (1.3)
//Sample textures
vec4 albedo_tex = texture2D(texture, texcoord);
vec4 normal_tex = texture2D(normals, texcoord);
vec4 specular_tex = texture2D(specular, texcoord);
//Gamma correction - Optional if you're not doing gamma correct lighting
albedo_tex.xyz = pow(albedo_tex.xyz, vec3(2.2));
//Normals
vec3 normal;
normal.xy = normal_tex.xy * 2.0 - 1.0; //Bring to -1 - 1 range
normal.z = sqrt(1.0-dot(normal.xy, normal.xy)); //Reconstruct Z
normal = tbn_matrix * normal; //Rotate by TBN matrix
normal = normal * 0.5 + 0.5; //0 - 1 range, buffers can't support negative values
//Ambient occlusion
float ao = normal_tex.z;
//Heightmap
float heightmap = normal_tex.w;
//Roughness - Converted from perceptural smoothness
float roughness = pow(1.0 - specular_tex.x, 2.0);
//F0
float F0 = specular_tex.y;
//Is our material metal?
bool is_metal = (specular_tex.y * 255.0) > 229.5;
//Subsurface and porosity
float subsurface = 0.0;
float porosity = 0.0;
//In case of future LabPBR versions, let's check for metals here
if(!is_metal)
{
//Thickness
subsurface = (specular_tex.z * 255.0) < 65.0 ? 0.0 : specular_tex.z;
//Porosity
porosity = (specular_tex.z * 255.0) > 64.0 ? 0.0 : specular_tex.z;
}
//Emmision
float emmision = (specular_tex.w * 255.0) < 254.5 ? specular_tex.w : 0.0;
@LVutner
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LVutner commented Jan 1, 2021

Don't forget to check LabPBR wiki to get more information about textures and shaders.
https://github.com/rre36/lab-pbr/wiki

@saadam1n
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Thank you so much!

@LVutner
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LVutner commented Jan 27, 2021

Thank you so much!

You're welcome :D

@null511
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null511 commented Jan 27, 2021

Shouldn't the SSS value be shifted down by the 65 pixel-value offset?

offset = 65.0 / 255.0;
subsurface = specular_tex.z < offset ? 0.0 : specular_tex.z - offset;

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