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[spline/bezier]Improve bezier tessellator more.

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xebra committed Feb 1, 2018
1 parent 068cc37 commit 4c6098d80123932fae0ab9af6e7a3a805d6b860c
Showing with 30 additions and 40 deletions.
  1. +30 −40 GPU/Common/SplineCommon.cpp
@@ -92,15 +92,6 @@ class Bezier3DWeight {
}
};
// http://en.wikipedia.org/wiki/Bernstein_polynomial
template<class T>
static T Bernstein3D(const T *p, const float w[4]) {
if (w[0] == 1) return p[0];
if (w[3] == 1) return p[3];
// Linear combination
return p[0] * w[0] + p[1] * w[1] + p[2] * w[2] + p[3] * w[3];
}
class Spline3DWeight {
private:
struct KnotDiv {
@@ -509,8 +500,24 @@ struct PrecomputedCurves {
PrecomputedCurves(int count) {
}
T Bernstein3D(int u, const float w[4]) {
return ::Bernstein3D(horiz, w);
// http://en.wikipedia.org/wiki/Bernstein_polynomial
template<class T>
static T Bernstein3D(const T p[4], const float w[4]) {
if (w[0] == 1) return p[0];
if (w[3] == 1) return p[3];
// Linear combination
return p[0] * w[0] + p[1] * w[1] + p[2] * w[2] + p[3] * w[3];
}
void Bernstein3D_U(const T *const p[16], const float w[4]) {
horiz[0] = Bernstein3D(p[0], w);
horiz[1] = Bernstein3D(p[4], w);
horiz[2] = Bernstein3D(p[8], w);
horiz[3] = Bernstein3D(p[12], w);
}
T Bernstein3D_V(const float w[4]) {
return Bernstein3D(horiz, w);
}
T horiz[4];
@@ -549,39 +556,22 @@ static void _BezierPatchHighQuality(u8 *&dest, u16 *&indices, int &count, int te
}
for (int tile_u = 0; tile_u < tess_u + 1; ++tile_u) {
const Weight &wu = weights.u[tile_u];
prepos.horiz[0] = Bernstein3D(_pos[0], wu.weights);
prepos.horiz[1] = Bernstein3D(_pos[4], wu.weights);
prepos.horiz[2] = Bernstein3D(_pos[8], wu.weights);
prepos.horiz[3] = Bernstein3D(_pos[12], wu.weights);
if (sampleColors) {
precol.horiz[0] = Bernstein3D(_col[0], wu.weights);
precol.horiz[1] = Bernstein3D(_col[4], wu.weights);
precol.horiz[2] = Bernstein3D(_col[8], wu.weights);
precol.horiz[3] = Bernstein3D(_col[12], wu.weights);
}
if (sampleTexcoords) {
pretex.horiz[0] = Bernstein3D(_tex[0], wu.weights);
pretex.horiz[1] = Bernstein3D(_tex[4], wu.weights);
pretex.horiz[2] = Bernstein3D(_tex[8], wu.weights);
pretex.horiz[3] = Bernstein3D(_tex[12], wu.weights);
}
if (computeNormals) {
prederivU.horiz[0] = Bernstein3D(_pos[0], wu.derivs);
prederivU.horiz[1] = Bernstein3D(_pos[4], wu.derivs);
prederivU.horiz[2] = Bernstein3D(_pos[8], wu.derivs);
prederivU.horiz[3] = Bernstein3D(_pos[12], wu.derivs);
}
prepos.Bernstein3D_U(_pos, wu.weights);
if (sampleColors)
precol.Bernstein3D_U(_col, wu.weights);
if (sampleTexcoords)
pretex.Bernstein3D_U(_tex, wu.weights);
if (computeNormals)
prederivU.Bernstein3D_U(_pos, wu.derivs);
for (int tile_v = 0; tile_v < tess_v + 1; ++tile_v) {
SimpleVertex &vert = vertices[tile_v * (tess_u + 1) + tile_u];
const Weight &wv = weights.v[tile_v];
if (computeNormals) {
const Vec3f derivU = prederivU.Bernstein3D(tile_u, wv.weights);
const Vec3f derivV = prepos.Bernstein3D(tile_u, wv.derivs);
const Vec3f derivU = prederivU.Bernstein3D_V(wv.weights);
const Vec3f derivV = prepos.Bernstein3D_V(wv.derivs);
vert.nrm = Cross(derivU, derivV).Normalized();
if (patch.patchFacing)
@@ -590,7 +580,7 @@ static void _BezierPatchHighQuality(u8 *&dest, u16 *&indices, int &count, int te
vert.nrm.SetZero();
}
vert.pos = prepos.Bernstein3D(tile_u, wv.weights);
vert.pos = prepos.Bernstein3D_V(wv.weights);
if (!sampleTexcoords) {
float u = ((float)tile_u / (float)tess_u);
@@ -600,13 +590,13 @@ static void _BezierPatchHighQuality(u8 *&dest, u16 *&indices, int &count, int te
vert.uv[1] = v + patch_u * third;
} else {
// Sample UV from control points
const Vec2f res = pretex.Bernstein3D(tile_u, wv.weights);
const Vec2f res = pretex.Bernstein3D_V(wv.weights);
vert.uv[0] = res.x;
vert.uv[1] = res.y;
}
if (sampleColors) {
vert.color_32 = precol.Bernstein3D(tile_u, wv.weights).ToRGBA();
vert.color_32 = precol.Bernstein3D_V(wv.weights).ToRGBA();
} else {
vert.color_32 = patch.defcolor;
}

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