/*!
* SamplePlanarTriangle(real xi_1, real xi_2)
* {
* Compute the warping function (xi_1, xi_2) -> (s, t).
* s <- sqrt(xi_1);
* t <- xi_2 ;
* Plug the warped coords into the original parametrization.
* P <- (1-s)*A + s*(1-t)*B + s*t*C;
* return P;
* }
*/
void Triangle::Sample(
__in xyz::float_t const &fXi1, ///< [in]
__in xyz::float_t const &fXi2, ///< [in]
__out xyz::float3_t *const pvPosition, ///< [out] 三角形上のサンプル位置
__out xyz::float3_t *const pvShadingNormal, ///< [out] シェーディング法線
__out xyz::float3_t *const pvGeometricNormal, ///< [out] 幾何学的法線
__out xyz::float3_t *const pvTangentVector, ///< [out] 接線ベクトル
__out xyz::float3_t *const pvBinormalVector ///< [out] 従法線ベクトル
) const {
float_t const s = std::sqrt(fXi1);
float_t const t = (fXi2);
float_t const u = s * (1 - t);
float_t const v = s * (t);
*pvPosition = Barycenter(v0_, e1_, e2_, u, v);
*pvShadingNormal = hi::normalize(Barycenter(n0_, s1_, s2_, u, v));
*pvGeometricNormal = ng_;
// 球面座標系をベースに基底を求める
*pvTangentVector =
float3_t(-(*pvGeometricNormal)[2], 0, (*pvGeometricNormal)[0]);
value_type const fLengthSquared = hi::length_squared(*pvTangentVector);
if (fLengthSquared > 0) {
// 接ベクトルから求める
*pvTangentVector *= hi::rsqrt(fLengthSquared);
*pvBinormalVector = BinormalVector(*pvTangentVector, *pvGeometricNormal);
} else {
// 従接ベクトルから求める
*pvBinormalVector = float3_t(0, 0, ((*pvGeometricNormal)[1] > 0) ? 1 : -1);
*pvTangentVector = TangentVector(*pvGeometricNormal, *pvBinormalVector);
}
}
void Triangle::ShadingBasis(__in Intersection const ¶m,
__out xyz::float3_t *const pvShadingNormal,
__out xyz::float3_t *const pvGeometricNormal,
__out xyz::float3_t *const pvTangent,
__out xyz::float3_t *const pvBinormal) const {
*pvShadingNormal =
hi::normalize(Barycenter(n0_, s1_, s2_, param.f(), param.g()));
*pvGeometricNormal = ng_;
if (param.is_back_side()) {
*pvGeometricNormal = -*pvGeometricNormal;
*pvShadingNormal = -*pvShadingNormal;
}
*pvTangent = float3_t(-(*pvShadingNormal)[2], 0, (*pvShadingNormal)[0]);
value_type const fLengthSquared = hi::length_squared(*pvTangent);
if (fLengthSquared > 0) {
// 接ベクトルから求める
*pvTangent *= hi::rsqrt(fLengthSquared);
*pvBinormal = BinormalVector(*pvTangent, *pvShadingNormal);
} else {
// 従接ベクトルから求める
*pvBinormal = float3_t(0, 0, ((*pvShadingNormal)[1] > 0) ? 1 : -1);
*pvTangent = TangentVector(*pvShadingNormal, *pvBinormal);
}
}
void VertexArray::add(double *x, double *y, double *z, SVector3 *n, unsigned char *r,
unsigned char *g, unsigned char *b, unsigned char *a,
MElement *ele, bool unique, bool boundary)
{
int npe = getNumVerticesPerElement();
if(boundary && npe == 3){
ElementData<3> e(x, y, z, n, r, g, b, a, ele);
ElementDataLessThan<3>::tolerance = (float)(CTX::instance()->lc * 1.e-12);
std::set<ElementData<3>, ElementDataLessThan<3> >::iterator it = _data3.find(e);
if(it == _data3.end())
_data3.insert(e);
else
_data3.erase(it);
return;
}
// enabling this will reduce memory and rendering time; but will increase the
// time it takes to create the vertex array
#if 0
if(unique){
Barycenter pc(0.0F, 0.0F, 0.0F);
for(int i = 0; i < npe; i++)
pc += Barycenter(x[i], y[i], z[i]);
BarycenterLessThan::tolerance = (float)(CTX::instance()->lc * 1.e-12);
if(_barycenters.find(pc) != _barycenters.end())
return;
_barycenters.insert(pc);
}
#endif
for(int i = 0; i < npe; i++){
_addVertex((float)x[i], (float)y[i], (float)z[i]);
if(n) _addNormal((float)n[i].x(), (float)n[i].y(), (float)n[i].z());
if(r && g && b && a) _addColor(r[i], g[i], b[i], a[i]);
_addElement(ele);
}
}
