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Cleanup.

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This commit is contained in:
Branimir Karadžić
2018-06-26 18:08:09 -07:00
parent dd9563d491
commit 31defc6701
1 changed files with 71 additions and 39 deletions
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110
src/image_cubemap_filter.cpp
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@@ -620,35 +620,39 @@ namespace bimg
}
}
void importanceSampleGGX(float* _result, const float* _xi, float _roughness, const float* _dir)
void importanceSampleGgx(float* _result, float _u, float _v, float _roughness, const float* _normal)
{
const float aa = bx::square(_roughness);
const float phi = bx::kPi2 * _xi[0];
const float cosTheta = bx::sqrt( (1.0f - _xi[1]) / (1.0f + (bx::square(aa) - 1.0f) * _xi[1]) );
const float sinTheta = bx::sqrt(1.0f - bx::square(cosTheta) );
const float phi = bx::kPi2 * _u;
const float cosTheta = bx::sqrt( (1.0f - _v) / (1.0f + (bx::square(aa) - 1.0f) * _v) );
const float sinTheta = bx::sqrt(bx::abs(1.0f - bx::square(cosTheta) ) );
float hh[3];
hh[0] = sinTheta * bx::cos(phi);
hh[1] = sinTheta * bx::sin(phi);
hh[2] = cosTheta;
const float hh[3] =
{
sinTheta * bx::cos(phi),
sinTheta * bx::sin(phi),
cosTheta,
};
float up[3] = { 0.0f, 0.0f, 0.0f };
up[bx::abs(_dir[2]) < 0.999f ? 2 : 0] = 1.0f;
up[bx::abs(_normal[2]) < 0.999f ? 2 : 0] = 1.0f;
float right[3];
bx::vec3Cross(right, up, _dir);
bx::vec3Cross(right, up, _normal);
float tangentX[3];
bx::vec3Norm(tangentX, right);
float tangentY[3];
bx::vec3Cross(tangentY, _dir, tangentX);
bx::vec3Cross(tangentY, _normal, tangentX);
_result[0] = tangentX[0] * hh[0] + tangentY[0] * hh[1] + _dir[0] * hh[2];
_result[1] = tangentX[1] * hh[0] + tangentY[1] * hh[1] + _dir[1] * hh[2];
_result[2] = tangentX[2] * hh[0] + tangentY[2] * hh[1] + _dir[2] * hh[2];
_result[0] = tangentX[0] * hh[0] + tangentY[0] * hh[1] + _normal[0] * hh[2];
_result[1] = tangentX[1] * hh[0] + tangentY[1] * hh[1] + _normal[1] * hh[2];
_result[2] = tangentX[2] * hh[0] + tangentY[2] * hh[1] + _normal[2] * hh[2];
}
#define GGX 0
void processFilterArea(
float* _result
, const ImageContainer& _image
@@ -696,7 +700,8 @@ namespace bimg
for (uint32_t xx = minX; xx <= maxX; ++xx)
{
#if 0
#if !GGX
# if 0
const float uu = float(xx)*texelSize*2.0f - 1.0f;
const float vv = float(yy)*texelSize*2.0f - 1.0f;
@@ -705,28 +710,11 @@ namespace bimg
const float solidAngle = texelSolidAngle(uu, vv, texelSize);
const float ndotl = bx::clamp(bx::vec3Dot(normal, _dir), 0.0f, 1.0f);
#elif 1
# else
const float* normal = (const float*)&nsaMip.m_data[(yy*nsaMip.m_width+xx)*(nsaMip.m_bpp/8)];
const float solidAngle = normal[3];
const float ndotl = bx::clamp(bx::vec3Dot(normal, _dir), 0.0f, 1.0f);
#else
const float uu = float(xx)*texelSize*2.0f - 1.0f;
const float vv = float(yy)*texelSize*2.0f - 1.0f;
float xi[2] = { uu, vv };
float hh[3];
importanceSampleGGX(hh, xi, _specularPower, _dir);
const float ddoth2 = 2.0f * bx::vec3Dot(_dir, hh);
float ll[3];
ll[0] = ddoth2 * hh[0] - _dir[0];
ll[1] = ddoth2 * hh[1] - _dir[1];
ll[2] = ddoth2 * hh[2] - _dir[2];
const float ndotl = bx::clamp(bx::vec3Dot(_dir, ll), 0.0f, 1.0f);
#endif // 0
# endif
if (ndotl >= _specularAngle)
{
const float weight = solidAngle * bx::pow(ndotl, _specularPower);
@@ -738,6 +726,47 @@ namespace bimg
color[2] += rgba[2] * weight;
totalWeight += weight;
}
#else
BX_UNUSED(_specularAngle);
const float uu = float(xx)*texelSize; //*2.0f - 1.0f;
const float vv = float(yy)*texelSize; //*2.0f - 1.0f;
const float* normal = (const float*)&nsaMip.m_data[(yy*nsaMip.m_width+xx)*(nsaMip.m_bpp/8)];
float hh[3];
importanceSampleGgx(hh, uu, vv, _specularPower, normal);
const float ddoth2 = 2.0f * bx::vec3Dot(normal, hh);
float ll[3];
ll[0] = ddoth2 * hh[0] - normal[0];
ll[1] = ddoth2 * hh[1] - normal[1];
ll[2] = ddoth2 * hh[2] - normal[2];
const float ndotl = bx::clamp(bx::vec3Dot(normal, ll), 0.0f, 1.0f);
// if (ndotl > 0.0f)
{
const float solidAngle = normal[3];
const float weight = solidAngle * ndotl;
float rgba[4];
unpack(rgba, row + xx*bpp/8);
# if 1
color[0] += rgba[0] * weight;
color[1] += rgba[1] * weight;
color[2] += rgba[2] * weight;
totalWeight += weight;
# else
color[0] += ll[0];
color[1] += ll[1];
color[2] += ll[2];
totalWeight += 1.0f;
# endif // 0
}
#endif // 0
}
}
@@ -849,11 +878,9 @@ namespace bimg
return bx::acos(bx::pow(treshold, 1.0f / _cosinePower));
}
float specularPowerFor(float _mip, float _mipCount, float _glossScale, float _glossBias)
float glossinessFor(float _mip, float _mipCount)
{
const float glossiness = bx::max(0.0f, 1.0f - _mip/(_mipCount-1.0000001f) );
const float specularPower = bx::pow(2.0f, _glossScale * glossiness + _glossBias);
return specularPower;
return bx::max(0.0f, 1.0f - _mip/(_mipCount-1.0000001f) );
}
float applyLightningModel(float _specularPower, LightingModel::Enum _lightingModel)
@@ -914,7 +941,8 @@ namespace bimg
const float minAngle = bx::atan2(1.0f, float(dstWidth) );
const float maxAngle = bx::kPiHalf;
const float toFilterSize = 1.0f/(minAngle*dstWidth*2.0f);
const float specularPowerRef = specularPowerFor(lod, float(numMips), _glossScale, _glossBias);
const float glossiness = glossinessFor(lod, float(numMips) );
const float specularPowerRef = bx::pow(2.0f, _glossScale * glossiness + _glossBias);
const float specularPower = applyLightningModel(specularPowerRef, _lightingModel);
const float filterAngle = bx::clamp(cosinePowerFilterAngle(specularPower), minAngle, maxAngle);
const float cosAngle = bx::max(0.0f, bx::cos(filterAngle) );
@@ -936,7 +964,11 @@ namespace bimg
Aabb aabb[6];
calcFilterArea(aabb, dir, filterSize);
#if GGX
processFilterArea(dstData, *input, *nsa, lod, aabb, dir, 1.0f-glossiness, cosAngle);
#else
processFilterArea(dstData, *input, *nsa, lod, aabb, dir, specularPower, cosAngle);
#endif // GGX
}
}
}