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#define EPSILON 0.00001
#define CAVITY_BUFFER_RANGE 4.0
/* From http://aras-p.info/texts/CompactNormalStorage.html
* Using Method #4: Spheremap Transform */
vec3 workbench_normal_decode(vec4 enc)
{
vec2 fenc = enc.xy * 4.0 - 2.0;
float f = dot(fenc, fenc);
float g = sqrt(1.0 - f / 4.0);
vec3 n;
n.xy = fenc * g;
n.z = 1 - f / 2;
return n;
}
/* From http://aras-p.info/texts/CompactNormalStorage.html
* Using Method #4: Spheremap Transform */
vec2 workbench_normal_encode(bool front_face, vec3 n)
{
n = normalize(front_face ? n : -n);
float p = sqrt(n.z * 8.0 + 8.0);
n.xy = clamp(n.xy / p + 0.5, 0.0, 1.0);
return n.xy;
}
/* Encoding into the alpha of a RGBA16F texture. (10bit mantissa) */
#define TARGET_BITCOUNT 8u
#define METALLIC_BITS 3u /* Metallic channel is less important. */
#define ROUGHNESS_BITS (TARGET_BITCOUNT - METALLIC_BITS)
/* Encode 2 float into 1 with the desired precision. */
float workbench_float_pair_encode(float v1, float v2)
{
// const uint v1_mask = ~(0xFFFFFFFFu << ROUGHNESS_BITS);
// const uint v2_mask = ~(0xFFFFFFFFu << METALLIC_BITS);
/* Same as above because some compiler are very dumb and think we use medium int. */
const int v1_mask = 0x1F;
const int v2_mask = 0x7;
int iv1 = int(v1 * float(v1_mask));
int iv2 = int(v2 * float(v2_mask)) << int(ROUGHNESS_BITS);
return float(iv1 | iv2);
}
void workbench_float_pair_decode(float data, out float v1, out float v2)
{
// const uint v1_mask = ~(0xFFFFFFFFu << ROUGHNESS_BITS);
// const uint v2_mask = ~(0xFFFFFFFFu << METALLIC_BITS);
/* Same as above because some compiler are very dumb and think we use medium int. */
const int v1_mask = 0x1F;
const int v2_mask = 0x7;
int idata = int(data);
v1 = float(idata & v1_mask) * (1.0 / float(v1_mask));
v2 = float(idata >> int(ROUGHNESS_BITS)) * (1.0 / float(v2_mask));
}
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