diff options
Diffstat (limited to 'thirdparty/thekla_atlas/nvmesh/raster/Raster.cpp')
-rw-r--r-- | thirdparty/thekla_atlas/nvmesh/raster/Raster.cpp | 626 |
1 files changed, 0 insertions, 626 deletions
diff --git a/thirdparty/thekla_atlas/nvmesh/raster/Raster.cpp b/thirdparty/thekla_atlas/nvmesh/raster/Raster.cpp deleted file mode 100644 index d46b34f045..0000000000 --- a/thirdparty/thekla_atlas/nvmesh/raster/Raster.cpp +++ /dev/null @@ -1,626 +0,0 @@ -// This code is in the public domain -- castanyo@yahoo.es - -/** @file Raster.cpp - * @brief Triangle rasterization library using affine interpolation. Not - * specially optimized, but enough for my purposes. -**/ - -#include "nvmesh.h" // pch - -#include "Raster.h" -#include "ClippedTriangle.h" - -#include "nvcore/Utils.h" // min, max - -#include "nvmath/Vector.inl" -#include "nvmath/ftoi.h" - - -#define RA_EPSILON 0.00001f - -using namespace nv; -using namespace nv::Raster; - -namespace -{ - static inline float delta(float bot, float top, float ih) - { - return (bot - top) * ih; - } - - static inline Vector2 delta(Vector2::Arg bot, Vector2::Arg top, float ih) - { - return (bot - top) * ih; - } - - static inline Vector3 delta(Vector3::Arg bot, Vector3::Arg top, float ih) - { - return (bot - top) * ih; - } - - // @@ The implementation in nvmath.h should be equivalent. - static inline int iround(float f) - { - // @@ Optimize this. - return int(floorf(f+0.5f)); - //return int(round(f)); - //return int(f); - } - - /// A triangle vertex. - struct Vertex - { - Vector2 pos; // Position. - Vector3 tex; // Texcoord. (Barycentric coordinate) - }; - - - /// A triangle for rasterization. - struct Triangle - { - Triangle(Vector2::Arg v0, Vector2::Arg v1, Vector2::Arg v2, Vector3::Arg t0, Vector3::Arg t1, Vector3::Arg t2); - - bool computeDeltas(); - - bool draw(const Vector2 & extents, bool enableScissors, SamplingCallback cb, void * param); - bool drawAA(const Vector2 & extents, bool enableScissors, SamplingCallback cb, void * param); - bool drawC(const Vector2 & extents, bool enableScissors, SamplingCallback cb, void * param); - void flipBackface(); - void computeUnitInwardNormals(); - - // Vertices. - Vector2 v1, v2, v3; - Vector2 n1, n2, n3; // unit inward normals - Vector3 t1, t2, t3; - - // Deltas. - Vector3 dx, dy; - - float sign; - bool valid; - }; - - - /// Triangle ctor. - Triangle::Triangle(Vector2::Arg v0, Vector2::Arg v1, Vector2::Arg v2, - Vector3::Arg t0, Vector3::Arg t1, Vector3::Arg t2) - { - // Init vertices. - this->v1 = v0; - this->v2 = v2; - this->v3 = v1; - - // Set barycentric coordinates. - this->t1 = t0; - this->t2 = t2; - this->t3 = t1; - - // make sure every triangle is front facing. - flipBackface(); - - // Compute deltas. - valid = computeDeltas(); - - computeUnitInwardNormals(); - } - - - /// Compute texture space deltas. - /// This method takes two edge vectors that form a basis, determines the - /// coordinates of the canonic vectors in that basis, and computes the - /// texture gradient that corresponds to those vectors. - bool Triangle::computeDeltas() - { - Vector2 e0 = v3 - v1; - Vector2 e1 = v2 - v1; - - Vector3 de0 = t3 - t1; - Vector3 de1 = t2 - t1; - - float denom = 1.0f / (e0.y * e1.x - e1.y * e0.x); - if (!isFinite(denom)) { - return false; - } - - float lambda1 = - e1.y * denom; - float lambda2 = e0.y * denom; - float lambda3 = e1.x * denom; - float lambda4 = - e0.x * denom; - - dx = de0 * lambda1 + de1 * lambda2; - dy = de0 * lambda3 + de1 * lambda4; - - return true; - } - - // compute unit inward normals for each edge. - void Triangle::computeUnitInwardNormals() - { - n1 = v1 - v2; n1 = Vector2(-n1.y, n1.x); n1 = n1 * (1.0f/sqrtf(n1.x*n1.x + n1.y*n1.y)); - n2 = v2 - v3; n2 = Vector2(-n2.y, n2.x); n2 = n2 * (1.0f/sqrtf(n2.x*n2.x + n2.y*n2.y)); - n3 = v3 - v1; n3 = Vector2(-n3.y, n3.x); n3 = n3 * (1.0f/sqrtf(n3.x*n3.x + n3.y*n3.y)); - } - - void Triangle::flipBackface() - { - // check if triangle is backfacing, if so, swap two vertices - if ( ((v3.x-v1.x)*(v2.y-v1.y) - (v3.y-v1.y)*(v2.x-v1.x)) < 0 ) { - Vector2 hv=v1; v1=v2; v2=hv; // swap pos - Vector3 ht=t1; t1=t2; t2=ht; // swap tex - } - } - - bool Triangle::draw(const Vector2 & extents, bool enableScissors, SamplingCallback cb, void * param) - { - // 28.4 fixed-point coordinates - const int Y1 = iround(16.0f * v1.y); - const int Y2 = iround(16.0f * v2.y); - const int Y3 = iround(16.0f * v3.y); - - const int X1 = iround(16.0f * v1.x); - const int X2 = iround(16.0f * v2.x); - const int X3 = iround(16.0f * v3.x); - - // Deltas - const int DX12 = X1 - X2; - const int DX23 = X2 - X3; - const int DX31 = X3 - X1; - - const int DY12 = Y1 - Y2; - const int DY23 = Y2 - Y3; - const int DY31 = Y3 - Y1; - - // Fixed-point deltas - const int FDX12 = DX12 << 4; - const int FDX23 = DX23 << 4; - const int FDX31 = DX31 << 4; - - const int FDY12 = DY12 << 4; - const int FDY23 = DY23 << 4; - const int FDY31 = DY31 << 4; - - int minx, miny, maxx, maxy; - if (enableScissors) { - int frustumX0 = 0 << 4; - int frustumY0 = 0 << 4; - int frustumX1 = (int)extents.x << 4; - int frustumY1 = (int)extents.y << 4; - - // Bounding rectangle - minx = (nv::max(min3(X1, X2, X3), frustumX0) + 0xF) >> 4; - miny = (nv::max(min3(Y1, Y2, Y3), frustumY0) + 0xF) >> 4; - maxx = (nv::min(max3(X1, X2, X3), frustumX1) + 0xF) >> 4; - maxy = (nv::min(max3(Y1, Y2, Y3), frustumY1) + 0xF) >> 4; - } - else { - // Bounding rectangle - minx = (min3(X1, X2, X3) + 0xF) >> 4; - miny = (min3(Y1, Y2, Y3) + 0xF) >> 4; - maxx = (max3(X1, X2, X3) + 0xF) >> 4; - maxy = (max3(Y1, Y2, Y3) + 0xF) >> 4; - } - - // Block size, standard 8x8 (must be power of two) - const int q = 8; - - // @@ This won't work when minx,miny are negative. This code path is not used. Leaving as is for now. - nvCheck(minx >= 0); - nvCheck(miny >= 0); - - // Start in corner of 8x8 block - minx &= ~(q - 1); - miny &= ~(q - 1); - - // Half-edge constants - int C1 = DY12 * X1 - DX12 * Y1; - int C2 = DY23 * X2 - DX23 * Y2; - int C3 = DY31 * X3 - DX31 * Y3; - - // Correct for fill convention - if(DY12 < 0 || (DY12 == 0 && DX12 > 0)) C1++; - if(DY23 < 0 || (DY23 == 0 && DX23 > 0)) C2++; - if(DY31 < 0 || (DY31 == 0 && DX31 > 0)) C3++; - - // Loop through blocks - for(int y = miny; y < maxy; y += q) - { - for(int x = minx; x < maxx; x += q) - { - // Corners of block - int x0 = x << 4; - int x1 = (x + q - 1) << 4; - int y0 = y << 4; - int y1 = (y + q - 1) << 4; - - // Evaluate half-space functions - bool a00 = C1 + DX12 * y0 - DY12 * x0 > 0; - bool a10 = C1 + DX12 * y0 - DY12 * x1 > 0; - bool a01 = C1 + DX12 * y1 - DY12 * x0 > 0; - bool a11 = C1 + DX12 * y1 - DY12 * x1 > 0; - int a = (a00 << 0) | (a10 << 1) | (a01 << 2) | (a11 << 3); - - bool b00 = C2 + DX23 * y0 - DY23 * x0 > 0; - bool b10 = C2 + DX23 * y0 - DY23 * x1 > 0; - bool b01 = C2 + DX23 * y1 - DY23 * x0 > 0; - bool b11 = C2 + DX23 * y1 - DY23 * x1 > 0; - int b = (b00 << 0) | (b10 << 1) | (b01 << 2) | (b11 << 3); - - bool c00 = C3 + DX31 * y0 - DY31 * x0 > 0; - bool c10 = C3 + DX31 * y0 - DY31 * x1 > 0; - bool c01 = C3 + DX31 * y1 - DY31 * x0 > 0; - bool c11 = C3 + DX31 * y1 - DY31 * x1 > 0; - int c = (c00 << 0) | (c10 << 1) | (c01 << 2) | (c11 << 3); - - // Skip block when outside an edge - if(a == 0x0 || b == 0x0 || c == 0x0) continue; - - // Accept whole block when totally covered - if(a == 0xF && b == 0xF && c == 0xF) - { - Vector3 texRow = t1 + dy*(y0 - v1.y) + dx*(x0 - v1.x); - - for(int iy = y; iy < y + q; iy++) - { - Vector3 tex = texRow; - for(int ix = x; ix < x + q; ix++) - { - //Vector3 tex = t1 + dx * (ix - v1.x) + dy * (iy - v1.y); - if (!cb(param, ix, iy, tex, dx, dy, 1.0)) { - // early out. - return false; - } - tex += dx; - } - texRow += dy; - } - } - else // Partially covered block - { - int CY1 = C1 + DX12 * y0 - DY12 * x0; - int CY2 = C2 + DX23 * y0 - DY23 * x0; - int CY3 = C3 + DX31 * y0 - DY31 * x0; - Vector3 texRow = t1 + dy*(y0 - v1.y) + dx*(x0 - v1.x); - - for(int iy = y; iy < y + q; iy++) - { - int CX1 = CY1; - int CX2 = CY2; - int CX3 = CY3; - Vector3 tex = texRow; - - for(int ix = x; ix < x + q; ix++) - { - if(CX1 > 0 && CX2 > 0 && CX3 > 0) - { - if (!cb(param, ix, iy, tex, dx, dy, 1.0)) - { - // early out. - return false; - } - } - - CX1 -= FDY12; - CX2 -= FDY23; - CX3 -= FDY31; - tex += dx; - } - - CY1 += FDX12; - CY2 += FDX23; - CY3 += FDX31; - texRow += dy; - } - } - } - } - - return true; - } - - -#define PX_INSIDE 1.0f/sqrt(2.0f) -#define PX_OUTSIDE -1.0f/sqrt(2.0f) - -#define BK_SIZE 8 -#define BK_INSIDE sqrt(BK_SIZE*BK_SIZE/2.0f) -#define BK_OUTSIDE -sqrt(BK_SIZE*BK_SIZE/2.0f) - - // extents has to be multiple of BK_SIZE!! - bool Triangle::drawAA(const Vector2 & extents, bool enableScissors, SamplingCallback cb, void * param) - { - float minx, miny, maxx, maxy; - if (enableScissors) { - // Bounding rectangle - minx = floorf(max(min3(v1.x, v2.x, v3.x), 0.0f)); - miny = floorf(max(min3(v1.y, v2.y, v3.y), 0.0f)); - maxx = ceilf( min(max3(v1.x, v2.x, v3.x), extents.x-1.0f)); - maxy = ceilf( min(max3(v1.y, v2.y, v3.y), extents.y-1.0f)); - } - else { - // Bounding rectangle - minx = floorf(min3(v1.x, v2.x, v3.x)); - miny = floorf(min3(v1.y, v2.y, v3.y)); - maxx = ceilf( max3(v1.x, v2.x, v3.x)); - maxy = ceilf( max3(v1.y, v2.y, v3.y)); - } - - // There's no reason to align the blocks to the viewport, instead we align them to the origin of the triangle bounds. - minx = floorf(minx); - miny = floorf(miny); - //minx = (float)(((int)minx) & (~((int)BK_SIZE - 1))); // align to blocksize (we don't need to worry about blocks partially out of viewport) - //miny = (float)(((int)miny) & (~((int)BK_SIZE - 1))); - - minx += 0.5; miny +=0.5; // sampling at texel centers! - maxx += 0.5; maxy +=0.5; - - // Half-edge constants - float C1 = n1.x * (-v1.x) + n1.y * (-v1.y); - float C2 = n2.x * (-v2.x) + n2.y * (-v2.y); - float C3 = n3.x * (-v3.x) + n3.y * (-v3.y); - - // Loop through blocks - for(float y0 = miny; y0 <= maxy; y0 += BK_SIZE) - { - for(float x0 = minx; x0 <= maxx; x0 += BK_SIZE) - { - // Corners of block - float xc = (x0 + (BK_SIZE-1)/2.0f); - float yc = (y0 + (BK_SIZE-1)/2.0f); - - // Evaluate half-space functions - float aC = C1 + n1.x * xc + n1.y * yc; - float bC = C2 + n2.x * xc + n2.y * yc; - float cC = C3 + n3.x * xc + n3.y * yc; - - // Skip block when outside an edge - if( (aC <= BK_OUTSIDE) || (bC <= BK_OUTSIDE) || (cC <= BK_OUTSIDE) ) continue; - - // Accept whole block when totally covered - if( (aC >= BK_INSIDE) && (bC >= BK_INSIDE) && (cC >= BK_INSIDE) ) - { - Vector3 texRow = t1 + dy*(y0 - v1.y) + dx*(x0 - v1.x); - - for (float y = y0; y < y0 + BK_SIZE; y++) - { - Vector3 tex = texRow; - for(float x = x0; x < x0 + BK_SIZE; x++) - { - if (!cb(param, (int)x, (int)y, tex, dx, dy, 1.0f)) - { - return false; - } - tex += dx; - } - texRow += dy; - } - } - else // Partially covered block - { - float CY1 = C1 + n1.x * x0 + n1.y * y0; - float CY2 = C2 + n2.x * x0 + n2.y * y0; - float CY3 = C3 + n3.x * x0 + n3.y * y0; - Vector3 texRow = t1 + dy*(y0 - v1.y) + dx*(x0 - v1.x); - - for(float y = y0; y < y0 + BK_SIZE; y++) // @@ This is not clipping to scissor rectangle correctly. - { - float CX1 = CY1; - float CX2 = CY2; - float CX3 = CY3; - Vector3 tex = texRow; - - for (float x = x0; x < x0 + BK_SIZE; x++) // @@ This is not clipping to scissor rectangle correctly. - { - if (CX1 >= PX_INSIDE && CX2 >= PX_INSIDE && CX3 >= PX_INSIDE) - { - // pixel completely covered - Vector3 tex = t1 + dx * (x - v1.x) + dy * (y - v1.y); - if (!cb(param, (int)x, (int)y, tex, dx, dy, 1.0f)) - { - return false; - } - } - else if ((CX1 >= PX_OUTSIDE) && (CX2 >= PX_OUTSIDE) && (CX3 >= PX_OUTSIDE)) - { - // triangle partially covers pixel. do clipping. - ClippedTriangle ct(v1-Vector2(x,y), v2-Vector2(x,y), v3-Vector2(x,y)); - ct.clipAABox(-0.5, -0.5, 0.5, 0.5); - Vector2 centroid = ct.centroid(); - float area = ct.area(); - if (area > 0.0f) - { - Vector3 texCent = tex - dx*centroid.x - dy*centroid.y; - //nvCheck(texCent.x >= -0.1f && texCent.x <= 1.1f); // @@ Centroid is not very exact... - //nvCheck(texCent.y >= -0.1f && texCent.y <= 1.1f); - //nvCheck(texCent.z >= -0.1f && texCent.z <= 1.1f); - //Vector3 texCent2 = t1 + dx * (x - v1.x) + dy * (y - v1.y); - if (!cb(param, (int)x, (int)y, texCent, dx, dy, area)) - { - return false; - } - } - } - - CX1 += n1.x; - CX2 += n2.x; - CX3 += n3.x; - tex += dx; - } - - CY1 += n1.y; - CY2 += n2.y; - CY3 += n3.y; - texRow += dy; - } - } - } - } - - return true; - } - -} // namespace - - -/// Process the given triangle. -bool nv::Raster::drawTriangle(Mode mode, Vector2::Arg extents, bool enableScissors, const Vector2 v[3], SamplingCallback cb, void * param) -{ - Triangle tri(v[0], v[1], v[2], Vector3(1, 0, 0), Vector3(0, 1, 0), Vector3(0, 0, 1)); - - // @@ It would be nice to have a conservative drawing mode that enlarges the triangle extents by one texel and is able to handle degenerate triangles. - // @@ Maybe the simplest thing to do would be raster triangle edges. - - if (tri.valid) { - if (mode == Mode_Antialiased) { - return tri.drawAA(extents, enableScissors, cb, param); - } - if (mode == Mode_Nearest) { - return tri.draw(extents, enableScissors, cb, param); - } - } - - return true; -} - -inline static float triangleArea(Vector2::Arg v1, Vector2::Arg v2, Vector2::Arg v3) -{ - return 0.5f * (v3.x * v1.y + v1.x * v2.y + v2.x * v3.y - v2.x * v1.y - v3.x * v2.y - v1.x * v3.y); -} - -/// Process the given quad. -bool nv::Raster::drawQuad(Mode mode, Vector2::Arg extents, bool enableScissors, const Vector2 v[4], SamplingCallback cb, void * param) -{ - bool sign0 = triangleArea(v[0], v[1], v[2]) > 0.0f; - bool sign1 = triangleArea(v[0], v[2], v[3]) > 0.0f; - - // Divide the quad into two non overlapping triangles. - if (sign0 == sign1) { - Triangle tri0(v[0], v[1], v[2], Vector3(0,0,0), Vector3(1,0,0), Vector3(1,1,0)); - Triangle tri1(v[0], v[2], v[3], Vector3(0,0,0), Vector3(1,1,0), Vector3(0,1,0)); - - if (tri0.valid && tri1.valid) { - if (mode == Mode_Antialiased) { - return tri0.drawAA(extents, enableScissors, cb, param) && tri1.drawAA(extents, enableScissors, cb, param); - } else { - return tri0.draw(extents, enableScissors, cb, param) && tri1.draw(extents, enableScissors, cb, param); - } - } - } - else - { - Triangle tri0(v[0], v[1], v[3], Vector3(0,0,0), Vector3(1,0,0), Vector3(0,1,0)); - Triangle tri1(v[1], v[2], v[3], Vector3(1,0,0), Vector3(1,1,0), Vector3(0,1,0)); - - if (tri0.valid && tri1.valid) { - if (mode == Mode_Antialiased) { - return tri0.drawAA(extents, enableScissors, cb, param) && tri1.drawAA(extents, enableScissors, cb, param); - } else { - return tri0.draw(extents, enableScissors, cb, param) && tri1.draw(extents, enableScissors, cb, param); - } - } - } - - return true; -} - - -static bool drawPoint(const Vector2 & p, const Vector2 v[2], LineSamplingCallback cb, void * param) { - - int x = ftoi_round(p.x); - int y = ftoi_round(p.y); - Vector2 ip = Vector2(float(x) + 0.5f, float(y) + 0.5f); - - float t; - - // Return minimum distance between line segment vw and point p - Vector2 dv = v[1] - v[0]; - const float l2 = nv::lengthSquared(dv); // i.e. |w-v|^2 - avoid a sqrt - if (l2 == 0.0) { - t = 0; // v0 == v1 case - } - else { - // Consider the line extending the segment, parameterized as v + t (w - v). - // We find projection of point p onto the line. - // It falls where t = [(p-v) . (w-v)] / |w-v|^2 - t = dot(ip - v[0], dv) / l2; - if (t < 0.0) { - t = 0; // Beyond the 'v0' end of the segment - } - else if (t > 1.0) { - t = 1; // Beyond the 'v1' end of the segment - } - } - - Vector2 projection = v[0] + t * dv; // Projection falls on the segment - - float d = distance(ip, projection); - - return cb(param, x, y, t, saturate(1-d)); -} - - -void nv::Raster::drawLine(bool antialias, Vector2::Arg extents, bool enableScissors, const Vector2 v[2], LineSamplingCallback cb, void * param) -{ - nvCheck(antialias == true); // @@ Not implemented. - //nvCheck(enableScissors == false); // @@ Not implemented. - - // Very crappy DDA implementation. - - Vector2 p = v[0]; - Vector2 dp, dpdy; - - float dx = v[1].x - v[0].x; - float dy = v[1].y - v[0].y; - int n; - - // Degenerate line. - if (dx == 0 && dy == 0) return; - - if (fabsf(dx) >= fabsf(dy)) { - n = iround(fabsf(dx)); - dp.x = dx / fabsf(dx); - dp.y = dy / fabsf(dx); - nvDebugCheck(fabsf(dp.y) <= 1.0f); - dpdy.x = 0; - dpdy.y = 1; - } - else { - n = iround(fabs(dy)); - dp.x = dx / fabsf(dy); - dp.y = dy / fabsf(dy); - nvDebugCheck(fabsf(dp.x) <= 1.0f); - dpdy.x = 1; - dpdy.y = 0; - } - - for (int i = 0; i <= n; i++) { - drawPoint(p, v, cb, param); - drawPoint(p + dpdy, v, cb, param); - drawPoint(p - dpdy, v, cb, param); - p += dp; - } -} - - -// Draw vertical or horizontal segments. For degenerate triangles. -/*bool nv::Raster::drawSegment(Vector2::Arg extents, bool enableScissors, const Vector2 v[2], LineSamplingCallback cb, void * param) -{ - nvCheck(enableScissors == false); - - - if (v[0].x == v[1].x) { // Vertical segment. - - } - else if (v[0].y == v[1].y) { // Horizontal segment. - int y = ftoi_round(v[0].y); - int x0 = ftoi_floor(v[0].x); - int x1 = ftoi_floor(v[0].x); - - for (int x = x0; x <= x1; x++) { - - cb(param, x, y, t, - } - } - - return false; // Not a valid segment. -} -*/ |