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Implement photon planes

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tunabrain committed Aug 25, 2017
1 parent 149a14a commit a3233951d948cda1141f4aa305982feae70d427d
@@ -0,0 +1,107 @@
#include "FrustumBinner.hpp"
namespace Tungsten {
FrustumBinner::FrustumBinner(const Camera &camera)
: _guardBand(3 + TileSize*1.41421f + 2.0f),
_res(camera.resolution()),
_aspect(_res.x()/float(_res.y())),
_f(1.0f/std::tan(camera.approximateFov()*0.5f)),
_scale(Vec2f(_f, -_f*_aspect)*0.5f),
_invT(camera.invTransform()),
_pos(camera.pos())
{
}
static inline Vec3f triangleSetup(const Vec2f &a, const Vec2f &b, float band)
{
float l = (b - a).length()*band + 1.0f;
return Vec3f(
a.y() - b.y(),
b.x() - a.x(),
(b.y() - a.y())*a.x() - (b.x() - a.x())*a.y() + l
);
}
static inline float orient2d(const Vec2f &a, const Vec2f &b, const Vec2f &c)
{
return (b.x() - a.x())*(c.y() - a.y()) - (b.y() - a.y())*(c.x() - a.x());
}
template<typename Vec>
void clip(const Vec *in, int inCount, Vec *out, int &outCount, Vec plane, float offs)
{
outCount = 0;
for (int i = 0; i < inCount; ++i) {
Vec p0 = in[(i + 0) % inCount];
Vec p1 = in[(i + 1) % inCount];
float u0 = p0.dot(plane);
float u1 = p1.dot(plane);
bool clip0 = u0 < offs;
bool clip1 = u1 < offs;
if (clip0 && clip1)
continue;
if (clip0)
p0 += (p1 - p0)*(offs - plane.dot(p0))/(plane.dot(p1 - p0));
else if (clip1)
p1 += (p0 - p1)*(offs - plane.dot(p1))/(plane.dot(p0 - p1));
out[outCount++] = p0;
if (clip1)
out[outCount++] = p1;
}
}
FrustumBinner::QuadSetup FrustumBinner::setupQuad(Vec3f p0, Vec3f p1, Vec3f p2, Vec3f p3) const
{
Vec3f vertices[] = {p0, p1, p2, p3};
Vec3f clippedVerts[5];
int clippedCount = 0;
const float eps = 1e-5f;
clip(vertices, 4, clippedVerts, clippedCount, Vec3f(0.0f, 0.0f, 1.0f), eps);
Vec2f screenVertsA[10], screenVertsB[10];
for (int j = 0; j < clippedCount; ++j)
screenVertsA[j] = (clippedVerts[j].xy()/std::abs(clippedVerts[j].z())*_scale + 0.5f);
int clippedCountA = clippedCount, clippedCountB;
clip(screenVertsA, clippedCountA, screenVertsB, clippedCountB, Vec2f( 1.0f, 0.0f), 0.0f);
clip(screenVertsB, clippedCountB, screenVertsA, clippedCountA, Vec2f( 0.0f, 1.0f), 0.0f);
clip(screenVertsA, clippedCountA, screenVertsB, clippedCountB, Vec2f(-1.0f, 0.0f), -1.0f);
clip(screenVertsB, clippedCountB, screenVertsA, clippedCountA, Vec2f( 0.0f, -1.0f), -1.0f);
Box2f bounds;
for (int i = 0; i < clippedCountA; ++i) {
screenVertsA[i] *= Vec2f(_res);
bounds.grow(screenVertsA[i]);
}
screenVertsA[clippedCountA] = screenVertsA[0];
bounds.grow(_guardBand);
int minX = max(int(bounds.min().x()), 0), maxX = min(int(bounds.max().x() + 1.0f), int(_res.x()));
int minY = max(int(bounds.min().y()), 0), maxY = min(int(bounds.max().y() + 1.0f), int(_res.y()));
float sign = orient2d(screenVertsA[0], screenVertsA[1], screenVertsA[2]) < 0.0f ? -1.0f : 1.0f;
Vec3f setups[12];
if (clippedCountA == 0) {
for (int j = 0; j < 12; ++j)
setups[j] = Vec3f(0.0f, 0.0f, -1.0f);
} else {
for (int j = 0; j < 12; ++j)
setups[j] = Vec3f(0.0f);
for (int j = 0; j < clippedCountA; ++j)
setups[j] = triangleSetup(screenVertsA[j], screenVertsA[j + 1], _guardBand*sign)*sign;
}
QuadSetup result;
result.bounds = Box2i(Vec2i(minX, minY), Vec2i(maxX, maxY));
for (int j = 0; j < 12; ++j) {
result.stepX [j/4][j % 4] = setups[j].x();
result.stepY [j/4][j % 4] = setups[j].y();
result.offset[j/4][j % 4] = setups[j].z();
}
return result;
}
}
@@ -0,0 +1,153 @@
#ifndef FRUSTUMBINNER_HPP_
#define FRUSTUMBINNER_HPP_
#include "cameras/Camera.hpp"
#include "math/Mat4f.hpp"
#include "math/Vec.hpp"
#include "math/Box.hpp"
#include "sse/SimdFloat.hpp"
#include "IntTypes.hpp"
#include <array>
namespace Tungsten {
class FrustumBinner
{
static constexpr uint32 TileSize = 4;
static constexpr uint32 TileMask = TileSize - 1;
static inline float minReduce(float4 a, float4 b, float4 c)
{
float4 reduce = min(min(a, b), c);
return min(min(reduce[0], reduce[1]), min(reduce[2], reduce[3]));
}
struct QuadSetup
{
Box2i bounds;
float4 stepX[3];
float4 stepY[3];
float4 offset[3];
float4 wy[3];
float4 wx[3];
inline void start(float x, float y)
{
float4 xf = float4(x);
float4 yf = float4(y);
wy[0] = stepX[0]*xf + stepY[0]*yf + offset[0];
wy[1] = stepX[1]*xf + stepY[1]*yf + offset[1];
wy[2] = stepX[2]*xf + stepY[2]*yf + offset[2];
}
inline void beginRow() { wx[0] = wy[0]; wx[1] = wy[1]; wx[2] = wy[2]; }
inline void endRow() { wy[0] += stepY[0]; wy[1] += stepY[1]; wy[2] += stepY[2]; }
inline void stepCol() { wx[0] += stepX[0]; wx[1] += stepX[1]; wx[2] += stepX[2]; }
inline float reduce() { return minReduce(wx[0], wx[1], wx[2]); }
};
float _guardBand;
Vec2u _res;
float _aspect;
float _f;
Vec2f _scale;
Mat4f _invT;
Vec3f _pos;
QuadSetup setupQuad(Vec3f p0, Vec3f p1, Vec3f p2, Vec3f p3) const;
public:
FrustumBinner(const Camera &camera);
template<size_t N, typename Intersector>
void iterateTiles(std::array<QuadSetup, N> quads, Intersector intersector) const
{
Box2i bounds;
for (const auto &q : quads)
bounds.grow(q.bounds);
if (bounds.empty())
return;
uint32 minX = uint32(bounds.min().x()) & ~TileMask, maxX = bounds.max().x();
uint32 minY = uint32(bounds.min().y()) & ~TileMask, maxY = bounds.max().y();
for (auto &q : quads) {
q.start(minX + TileSize*0.5f, minY + TileSize*0.5f);
for (int k = 0; k < 3; ++k) {
q.stepX[k] *= float(TileSize);
q.stepY[k] *= float(TileSize);
}
}
for (uint32 y = minY; y < maxY; y += TileSize) {
for (auto &q : quads)
q.beginRow();
for (uint32 x = minX; x < maxX; x += TileSize) {
float wMin = -1.0f;
for (auto &q : quads)
wMin = max(wMin, q.reduce());
if (wMin >= 0.0f) {
uint32 xjMax = min(x + TileSize, _res.x());
uint32 yjMax = min(y + TileSize, _res.y());
for (uint32 yj = y; yj < yjMax; ++yj)
for (uint32 xj = x; xj < xjMax; ++xj)
intersector(xj, yj, xj + yj*_res.x());
}
for (auto &q : quads)
q.stepCol();
}
for (auto &q : quads)
q.endRow();
}
}
template<typename Intersector>
void binBeam(Vec3f b0, Vec3f b1, Vec3f u, float radius, Intersector intersector) const
{
Vec3f p0 = _invT*(b0 - u*radius);
Vec3f p1 = _invT*(b0 + u*radius);
Vec3f p2 = _invT*(b1 + u*radius);
Vec3f p3 = _invT*(b1 - u*radius);
std::array<QuadSetup, 1> quads{{setupQuad(p0, p1, p2, p3)}};
iterateTiles(quads, intersector);
}
template<typename Intersector>
void binPlane(Vec3f p0, Vec3f p1, Vec3f p2, Vec3f p3, Intersector intersector) const
{
std::array<QuadSetup, 1> quads{{setupQuad(_invT*p0, _invT*p1, _invT*p2, _invT*p3)}};
iterateTiles(quads, intersector);
}
template<typename Intersector>
void binPlane1D(Vec3f center, Vec3f a, Vec3f b, Vec3f c, Intersector intersector) const
{
center = _invT*center;
a = _invT.transformVector(a);
b = _invT.transformVector(b);
c = _invT.transformVector(c);
std::array<QuadSetup, 6> quads{{
setupQuad(center + c - a - b, center + c - a + b, center + c + a + b, center + c + a - b),
setupQuad(center - c - a - b, center - c - a + b, center - c + a + b, center - c + a - b),
setupQuad(center + b - a - c, center + b - a + c, center + b + a + c, center + b + a - c),
setupQuad(center - b - a - c, center - b - a + c, center - b + a + c, center - b + a - c),
setupQuad(center + a - b - c, center + a - b + c, center + a + b + c, center + a + b - c),
setupQuad(center - a - b - c, center - a - b + c, center - a + b + c, center - a + b - c)
}};
iterateTiles(quads, intersector);
}
};
}
#endif /* FRUSTUMBINNER_HPP_ */
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