From a1ba371eede7d365ae5139866f4685cd8faa86ba Mon Sep 17 00:00:00 2001 From: Magnus Norddahl Date: Mon, 31 Oct 2016 06:09:46 +0100 Subject: [PATCH] Added triangle drawer to the software renderer --- src/CMakeLists.txt | 1 + src/r_triangle.cpp | 715 +++++++++++++++++++++++++++++++++++++++++++++ src/r_triangle.h | 96 ++++++ 3 files changed, 812 insertions(+) create mode 100644 src/r_triangle.cpp create mode 100644 src/r_triangle.h diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt index 09e220143..bb00af82d 100644 --- a/src/CMakeLists.txt +++ b/src/CMakeLists.txt @@ -936,6 +936,7 @@ set( FASTMATH_PCH_SOURCES r_segs.cpp r_sky.cpp r_things.cpp + r_triangle.cpp s_advsound.cpp s_environment.cpp s_playlist.cpp diff --git a/src/r_triangle.cpp b/src/r_triangle.cpp new file mode 100644 index 000000000..429f4a62a --- /dev/null +++ b/src/r_triangle.cpp @@ -0,0 +1,715 @@ +/* +** Triangle drawers +** Copyright (c) 2016 Magnus Norddahl +** +** This software is provided 'as-is', without any express or implied +** warranty. In no event will the authors be held liable for any damages +** arising from the use of this software. +** +** Permission is granted to anyone to use this software for any purpose, +** including commercial applications, and to alter it and redistribute it +** freely, subject to the following restrictions: +** +** 1. The origin of this software must not be misrepresented; you must not +** claim that you wrote the original software. If you use this software +** in a product, an acknowledgment in the product documentation would be +** appreciated but is not required. +** 2. Altered source versions must be plainly marked as such, and must not be +** misrepresented as being the original software. +** 3. This notice may not be removed or altered from any source distribution. +** +*/ + +#include +#include "templates.h" +#include "doomdef.h" +#include "i_system.h" +#include "w_wad.h" +#include "r_local.h" +#include "v_video.h" +#include "doomstat.h" +#include "st_stuff.h" +#include "g_game.h" +#include "g_level.h" +#include "r_data/r_translate.h" +#include "v_palette.h" +#include "r_data/colormaps.h" +#include "r_triangle.h" + +void TriangleDrawer::draw(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, FTexture *texture) +{ + draw_any(objectToWorld, vinput, vcount, ccw, clipleft, clipright, cliptop, clipbottom, texture, 0, &ScreenTriangleDrawer::draw); +} + +void TriangleDrawer::fill(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, int solidcolor) +{ + draw_any(objectToWorld, vinput, vcount, ccw, clipleft, clipright, cliptop, clipbottom, nullptr, solidcolor, &ScreenTriangleDrawer::fill); +} + +void TriangleDrawer::draw_any(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, FTexture *texture, int solidcolor, void(*drawfunc)(const ScreenTriangleDrawerArgs *)) +{ + for (int i = 0; i < vcount / 3; i++) + { + TriVertex vert[3]; + + // Vertex shader stuff: + for (int j = 0; j < 3; j++) + { + auto &v = vert[j]; + v = *(vinput++); + + // Apply transform to get world coordinates: + v = objectToWorld * v; + + // The software renderer world to clip transform: + double nearp = 5.0f; + double farp = 65536.f; + double tr_x = v.x - ViewPos.X; + double tr_y = v.y - ViewPos.Y; + double tr_z = v.z - ViewPos.Z; + double tx = tr_x * ViewSin - tr_y * ViewCos; + double tz = tr_x * ViewTanCos + tr_y * ViewTanSin; + v.x = (float)tx * 0.5f; + v.y = (float)tr_z * 0.5f; + v.z = (float)((-tz * (farp + nearp) / (nearp - farp) + (2.0f * farp * nearp) / (nearp - farp))); + v.w = (float)tz; + } + + // Cull, clip and generate additional vertices as needed + TriVertex clippedvert[6]; + int numclipvert = 0; + clipedge(vert[0], vert[1], clippedvert, numclipvert); + clipedge(vert[1], vert[2], clippedvert, numclipvert); + clipedge(vert[2], vert[0], clippedvert, numclipvert); + + // Map to 2D viewport: + for (int j = 0; j < numclipvert; j++) + { + auto &v = clippedvert[j]; + + // Calculate normalized device coordinates: + v.w = 1.0f / v.w; + v.x *= v.w; + v.y *= v.w; + v.z *= v.w; + + // Apply viewport scale to get screen coordinates: + v.x = (float)(CenterX + v.x * 2.0f * CenterX); + v.y = (float)(CenterY - v.y * 2.0f * InvZtoScale); + } + + // Draw screen triangles + + ScreenTriangleDrawerArgs args; + args.dest = dc_destorg; + args.pitch = dc_pitch; + args.clipleft = clipleft; + args.clipright = clipright; + args.cliptop = cliptop; + args.clipbottom = clipbottom; + if (texture) + { + args.textureWidth = texture->GetWidth(); + args.textureHeight = texture->GetHeight(); + args.texturePixels = texture->GetPixels(); + } + else + { + args.textureWidth = 0; + args.textureHeight = 0; + args.texturePixels = nullptr; + } + args.solidcolor = solidcolor; + + if (ccw) + { + for (int i = numclipvert; i > 1; i--) + { + args.v1 = &clippedvert[numclipvert - 1]; + args.v2 = &clippedvert[i - 1]; + args.v3 = &clippedvert[i - 2]; + drawfunc(&args); + } + } + else + { + for (int i = 2; i < numclipvert; i++) + { + args.v1 = &clippedvert[0]; + args.v2 = &clippedvert[i - 1]; + args.v3 = &clippedvert[i]; + drawfunc(&args); + } + } + } +} + +bool TriangleDrawer::cullhalfspace(float clipdistance1, float clipdistance2, float &t1, float &t2) +{ + float d1 = clipdistance1 * (1.0f - t1) + clipdistance2 * t1; + float d2 = clipdistance1 * (1.0f - t2) + clipdistance2 * t2; + if (d1 < 0.0f && d2 < 0.0f) + return true; + + if (d1 < 0.0f) + t1 = MAX(-clipdistance1 / (clipdistance2 - clipdistance1), t1); + + if (d2 < 0.0f) + t2 = MIN(1.0f + clipdistance2 / (clipdistance1 - clipdistance2), t2); + + return false; +} + +void TriangleDrawer::clipedge(const TriVertex &v1, const TriVertex &v2, TriVertex *clippedvert, int &numclipvert) +{ + // Clip and cull so that the following is true for all vertices: + // -v.w <= v.x <= v.w + // -v.w <= v.y <= v.w + // -v.w <= v.z <= v.w + + float t1 = 0.0f, t2 = 1.0f; + bool culled = + cullhalfspace(v1.x + v1.w, v2.x + v2.w, t1, t2) || + cullhalfspace(v1.w - v1.x, v2.w - v2.x, t1, t2) || + cullhalfspace(v1.y + v1.w, v2.y + v2.w, t1, t2) || + cullhalfspace(v1.w - v1.y, v2.w - v2.y, t1, t2) || + cullhalfspace(v1.z + v1.w, v2.z + v2.w, t1, t2) || + cullhalfspace(v1.w - v1.z, v2.w - v2.z, t1, t2); + if (culled) + return; + + if (t1 == 0.0f) + { + clippedvert[numclipvert++] = v1; + } + else + { + auto &v = clippedvert[numclipvert++]; + v.x = v1.x * (1.0f - t1) + v2.x * t1; + v.y = v1.y * (1.0f - t1) + v2.y * t1; + v.z = v1.z * (1.0f - t1) + v2.z * t1; + v.w = v1.w * (1.0f - t1) + v2.w * t1; + for (int i = 0; i < TriVertex::NumVarying; i++) + v.varying[i] = v1.varying[i] * (1.0f - t1) + v2.varying[i] * t1; + } + + if (t2 != 1.0f) + { + auto &v = clippedvert[numclipvert++]; + v.x = v1.x * (1.0f - t2) + v2.x * t2; + v.y = v1.y * (1.0f - t2) + v2.y * t2; + v.z = v1.z * (1.0f - t2) + v2.z * t2; + v.w = v1.w * (1.0f - t2) + v2.w * t2; + for (int i = 0; i < TriVertex::NumVarying; i++) + v.varying[i] = v1.varying[i] * (1.0f - t2) + v2.varying[i] * t2; + } +} + +///////////////////////////////////////////////////////////////////////////// + +void ScreenTriangleDrawer::draw(const ScreenTriangleDrawerArgs *args) +{ + uint8_t *dest = args->dest; + int pitch = args->pitch; + const TriVertex &v1 = *args->v1; + const TriVertex &v2 = *args->v2; + const TriVertex &v3 = *args->v3; + int clipleft = args->clipleft; + int clipright = args->clipright; + const short *cliptop = args->cliptop; + const short *clipbottom = args->clipbottom; + const uint8_t *texturePixels = args->texturePixels; + int textureWidth = args->textureWidth; + int textureHeight = args->textureHeight; + + // 28.4 fixed-point coordinates + const int Y1 = (int)round(16.0f * v1.y); + const int Y2 = (int)round(16.0f * v2.y); + const int Y3 = (int)round(16.0f * v3.y); + + const int X1 = (int)round(16.0f * v1.x); + const int X2 = (int)round(16.0f * v2.x); + const int X3 = (int)round(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; + + // Bounding rectangle + int clipymin = cliptop[clipleft]; + int clipymax = clipbottom[clipleft]; + for (int i = clipleft + 1; i <= clipright; i++) + { + clipymin = MIN(clipymin, (int)cliptop[i]); + clipymax = MAX(clipymax, (int)clipbottom[i]); + } + int minx = MAX((MIN(MIN(X1, X2), X3) + 0xF) >> 4, clipleft); + int maxx = MIN((MAX(MAX(X1, X2), X3) + 0xF) >> 4, clipright); + int miny = MAX((MIN(MIN(Y1, Y2), Y3) + 0xF) >> 4, clipymin); + int maxy = MIN((MAX(MAX(Y1, Y2), Y3) + 0xF) >> 4, clipymax - 1); + if (minx >= maxx || miny >= maxy) + return; + + // Block size, standard 8x8 (must be power of two) + const int q = 8; + + // Start in corner of 8x8 block + minx &= ~(q - 1); + miny &= ~(q - 1); + + dest += miny * pitch; + + // 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++; + + // Gradients + float gradWX = gradx(v1.x, v1.y, v2.x, v2.y, v3.x, v3.y, v1.w, v2.w, v3.w); + float gradWY = grady(v1.x, v1.y, v2.x, v2.y, v3.x, v3.y, v1.w, v2.w, v3.w); + float startW = v1.w + gradWX * (minx - v1.x) + gradWY * (miny - v1.y); + float gradVaryingX[TriVertex::NumVarying], gradVaryingY[TriVertex::NumVarying], startVarying[TriVertex::NumVarying]; + for (int i = 0; i < TriVertex::NumVarying; i++) + { + gradVaryingX[i] = gradx(v1.x, v1.y, v2.x, v2.y, v3.x, v3.y, v1.varying[i] * v1.w, v2.varying[i] * v2.w, v3.varying[i] * v3.w); + gradVaryingY[i] = grady(v1.x, v1.y, v2.x, v2.y, v3.x, v3.y, v1.varying[i] * v1.w, v2.varying[i] * v2.w, v3.varying[i] * v3.w); + startVarying[i] = v1.varying[i] * v1.w + gradVaryingX[i] * (minx - v1.x) + gradVaryingY[i] * (miny - v1.y); + } + + // 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; + + // Check if block needs clipping + int clipcount = 0; + for (int ix = x; ix < x + q; ix++) + { + clipcount += (clipleft > ix) || (clipright < ix) || (cliptop[ix] > y) || (clipbottom[ix] <= y + q - 1); + } + + // Calculate varying variables for affine block + float offx0 = (x - minx) + 0.5f; + float offy0 = (y - miny) + 0.5f; + float offx1 = offx0 + q; + float offy1 = offy0 + q; + float rcpWTL = 1.0f / (startW + offx0 * gradWX + offy0 * gradWY); + float rcpWTR = 1.0f / (startW + offx1 * gradWX + offy0 * gradWY); + float rcpWBL = 1.0f / (startW + offx0 * gradWX + offy1 * gradWY); + float rcpWBR = 1.0f / (startW + offx1 * gradWX + offy1 * gradWY); + float varyingTL[TriVertex::NumVarying]; + float varyingTR[TriVertex::NumVarying]; + float varyingBL[TriVertex::NumVarying]; + float varyingBR[TriVertex::NumVarying]; + for (int i = 0; i < TriVertex::NumVarying; i++) + { + varyingTL[i] = (startVarying[i] + offx0 * gradVaryingX[i] + offy0 * gradVaryingY[i]) * rcpWTL; + varyingTR[i] = (startVarying[i] + offx1 * gradVaryingX[i] + offy0 * gradVaryingY[i]) * rcpWTR; + varyingBL[i] = ((startVarying[i] + offx0 * gradVaryingX[i] + offy1 * gradVaryingY[i]) * rcpWBL - varyingTL[i]) * (1.0f / q); + varyingBR[i] = ((startVarying[i] + offx1 * gradVaryingX[i] + offy1 * gradVaryingY[i]) * rcpWBR - varyingTR[i]) * (1.0f / q); + } + + uint8_t *buffer = dest; + + // Accept whole block when totally covered + if (a == 0xF && b == 0xF && c == 0xF && clipcount == 0) + { + for (int iy = 0; iy < q; iy++) + { + float varying[TriVertex::NumVarying], varyingStep[TriVertex::NumVarying]; + for (int i = 0; i < TriVertex::NumVarying; i++) + { + varying[i] = varyingTL[i] + varyingBL[i] * iy; + varyingStep[i] = (varyingTR[i] + varyingBR[i] * iy - varying[i]) * (1.0f / q); + } + + for (int ix = x; ix < x + q; ix++) + { + uint32_t ufrac = (uint32_t)((varying[0] - floor(varying[0])) * 0x100000000LL); + uint32_t vfrac = (uint32_t)((varying[1] - floor(varying[1])) * 0x100000000LL); + //uint32_t light = (uint32_t)clamp(varying[2] * 255.0f + 0.5f, 0.0f, 255.0f); + + uint32_t upos = ((ufrac >> 16) * textureWidth) >> 16; + uint32_t vpos = ((vfrac >> 16) * textureHeight) >> 16; + uint32_t uvoffset = upos * textureHeight + vpos; + + buffer[ix] = texturePixels[uvoffset]; + + for (int i = 0; i < TriVertex::NumVarying; i++) + varying[i] += varyingStep[i]; + } + + buffer += pitch; + } + } + 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; + + for (int iy = 0; iy < q; iy++) + { + int CX1 = CY1; + int CX2 = CY2; + int CX3 = CY3; + + float varying[TriVertex::NumVarying], varyingStep[TriVertex::NumVarying]; + for (int i = 0; i < TriVertex::NumVarying; i++) + { + varying[i] = varyingTL[i] + varyingBL[i] * iy; + varyingStep[i] = (varyingTR[i] + varyingBR[i] * iy - varying[i]) * (1.0f / q); + } + + for (int ix = x; ix < x + q; ix++) + { + bool visible = ix >= clipleft && ix <= clipright && (cliptop[ix] <= y + iy) && (clipbottom[ix] > y + iy); + + if (CX1 > 0 && CX2 > 0 && CX3 > 0 && visible) + { + uint32_t ufrac = (uint32_t)((varying[0] - floor(varying[0])) * 0x100000000LL); + uint32_t vfrac = (uint32_t)((varying[1] - floor(varying[1])) * 0x100000000LL); + //uint32_t light = (uint32_t)clamp(varying[2] * 255.0f + 0.5f, 0.0f, 255.0f); + + uint32_t upos = ((ufrac >> 16) * textureWidth) >> 16; + uint32_t vpos = ((vfrac >> 16) * textureHeight) >> 16; + uint32_t uvoffset = upos * textureHeight + vpos; + + buffer[ix] = texturePixels[uvoffset]; + } + + for (int i = 0; i < TriVertex::NumVarying; i++) + varying[i] += varyingStep[i]; + + CX1 -= FDY12; + CX2 -= FDY23; + CX3 -= FDY31; + } + + CY1 += FDX12; + CY2 += FDX23; + CY3 += FDX31; + + buffer += pitch; + } + } + } + + dest += q * pitch; + } +} + +void ScreenTriangleDrawer::fill(const ScreenTriangleDrawerArgs *args) +{ + uint8_t *dest = args->dest; + int pitch = args->pitch; + const TriVertex &v1 = *args->v1; + const TriVertex &v2 = *args->v2; + const TriVertex &v3 = *args->v3; + int clipleft = args->clipleft; + int clipright = args->clipright; + const short *cliptop = args->cliptop; + const short *clipbottom = args->clipbottom; + int solidcolor = args->solidcolor; + + // 28.4 fixed-point coordinates + const int Y1 = (int)round(16.0f * v1.y); + const int Y2 = (int)round(16.0f * v2.y); + const int Y3 = (int)round(16.0f * v3.y); + + const int X1 = (int)round(16.0f * v1.x); + const int X2 = (int)round(16.0f * v2.x); + const int X3 = (int)round(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; + + // Bounding rectangle + int clipymin = cliptop[clipleft]; + int clipymax = clipbottom[clipleft]; + for (int i = clipleft + 1; i <= clipright; i++) + { + clipymin = MIN(clipymin, (int)cliptop[i]); + clipymax = MAX(clipymax, (int)clipbottom[i]); + } + int minx = MAX((MIN(MIN(X1, X2), X3) + 0xF) >> 4, clipleft); + int maxx = MIN((MAX(MAX(X1, X2), X3) + 0xF) >> 4, clipright); + int miny = MAX((MIN(MIN(Y1, Y2), Y3) + 0xF) >> 4, clipymin); + int maxy = MIN((MAX(MAX(Y1, Y2), Y3) + 0xF) >> 4, clipymax - 1); + if (minx >= maxx || miny >= maxy) + return; + + // Block size, standard 8x8 (must be power of two) + const int q = 8; + + // Start in corner of 8x8 block + minx &= ~(q - 1); + miny &= ~(q - 1); + + dest += miny * pitch; + + // 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; + + // Check if block needs clipping + int clipcount = 0; + for (int ix = x; ix < x + q; ix++) + { + clipcount += (clipleft > ix) || (clipright < ix) || (cliptop[ix] > y) || (clipbottom[ix] <= y + q - 1); + } + + uint8_t *buffer = dest; + + // Accept whole block when totally covered + if (a == 0xF && b == 0xF && c == 0xF && clipcount == 0) + { + for (int iy = 0; iy < q; iy++) + { + for (int ix = x; ix < x + q; ix++) + { + buffer[ix] = solidcolor; + } + + buffer += pitch; + } + } + 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; + + for (int iy = 0; iy < q; iy++) + { + int CX1 = CY1; + int CX2 = CY2; + int CX3 = CY3; + + for (int ix = x; ix < x + q; ix++) + { + bool visible = ix >= clipleft && ix <= clipright && (cliptop[ix] <= y + iy) && (clipbottom[ix] > y + iy); + + if (CX1 > 0 && CX2 > 0 && CX3 > 0 && visible) + { + buffer[ix] = solidcolor; + } + + CX1 -= FDY12; + CX2 -= FDY23; + CX3 -= FDY31; + } + + CY1 += FDX12; + CY2 += FDX23; + CY3 += FDX31; + + buffer += pitch; + } + } + } + + dest += q * pitch; + } +} + +float ScreenTriangleDrawer::gradx(float x0, float y0, float x1, float y1, float x2, float y2, float c0, float c1, float c2) +{ + float top = (c1 - c2) * (y0 - y2) - (c0 - c2) * (y1 - y2); + float bottom = (x1 - x2) * (y0 - y2) - (x0 - x2) * (y1 - y2); + return top / bottom; +} + +float ScreenTriangleDrawer::grady(float x0, float y0, float x1, float y1, float x2, float y2, float c0, float c1, float c2) +{ + float top = (c1 - c2) * (x0 - x2) - (c0 - c2) * (x1 - x2); + float bottom = -((x1 - x2) * (y0 - y2) - (x0 - x2) * (y1 - y2)); + return top / bottom; +} + +///////////////////////////////////////////////////////////////////////////// + +TriMatrix TriMatrix::null() +{ + TriMatrix m; + memset(m.matrix, 0, sizeof(m.matrix)); + return m; +} + +TriMatrix TriMatrix::identity() +{ + TriMatrix m = null(); + m.matrix[0] = 1.0f; + m.matrix[5] = 1.0f; + m.matrix[10] = 1.0f; + m.matrix[15] = 1.0f; + return m; +} + +TriMatrix TriMatrix::translate(float x, float y, float z) +{ + TriMatrix m = identity(); + m.matrix[0 + 3 * 4] = x; + m.matrix[1 + 3 * 4] = y; + m.matrix[2 + 3 * 4] = z; + return m; +} + +TriMatrix TriMatrix::scale(float x, float y, float z) +{ + TriMatrix m = null(); + m.matrix[0 + 0 * 4] = x; + m.matrix[1 + 1 * 4] = y; + m.matrix[2 + 2 * 4] = z; + m.matrix[3 + 3 * 4] = 1; + return m; +} + +TriMatrix TriMatrix::rotate(float angle, float x, float y, float z) +{ + float c = cosf(angle); + float s = sinf(angle); + TriMatrix m = null(); + m.matrix[0 + 0 * 4] = (x*x*(1.0f - c) + c); + m.matrix[0 + 1 * 4] = (x*y*(1.0f - c) - z*s); + m.matrix[0 + 2 * 4] = (x*z*(1.0f - c) + y*s); + m.matrix[1 + 0 * 4] = (y*x*(1.0f - c) + z*s); + m.matrix[1 + 1 * 4] = (y*y*(1.0f - c) + c); + m.matrix[1 + 2 * 4] = (y*z*(1.0f - c) - x*s); + m.matrix[2 + 0 * 4] = (x*z*(1.0f - c) - y*s); + m.matrix[2 + 1 * 4] = (y*z*(1.0f - c) + x*s); + m.matrix[2 + 2 * 4] = (z*z*(1.0f - c) + c); + m.matrix[3 + 3 * 4] = 1.0f; + return m; +} + +TriMatrix TriMatrix::operator*(const TriMatrix &mult) const +{ + TriMatrix result; + for (int x = 0; x < 4; x++) + { + for (int y = 0; y < 4; y++) + { + result.matrix[x + y * 4] = + matrix[0 * 4 + x] * mult.matrix[y * 4 + 0] + + matrix[1 * 4 + x] * mult.matrix[y * 4 + 1] + + matrix[2 * 4 + x] * mult.matrix[y * 4 + 2] + + matrix[3 * 4 + x] * mult.matrix[y * 4 + 3]; + } + } + return result; +} + +TriVertex TriMatrix::operator*(TriVertex v) const +{ + float vx = matrix[0 * 4 + 0] * v.x + matrix[1 * 4 + 0] * v.y + matrix[2 * 4 + 0] * v.z + matrix[3 * 4 + 0] * v.w; + float vy = matrix[0 * 4 + 1] * v.x + matrix[1 * 4 + 1] * v.y + matrix[2 * 4 + 1] * v.z + matrix[3 * 4 + 1] * v.w; + float vz = matrix[0 * 4 + 2] * v.x + matrix[1 * 4 + 2] * v.y + matrix[2 * 4 + 2] * v.z + matrix[3 * 4 + 2] * v.w; + float vw = matrix[0 * 4 + 3] * v.x + matrix[1 * 4 + 3] * v.y + matrix[2 * 4 + 3] * v.z + matrix[3 * 4 + 3] * v.w; + v.x = vx; + v.y = vy; + v.z = vz; + v.w = vw; + return v; +} diff --git a/src/r_triangle.h b/src/r_triangle.h new file mode 100644 index 000000000..2cd98bdd6 --- /dev/null +++ b/src/r_triangle.h @@ -0,0 +1,96 @@ +/* +** Triangle drawers +** Copyright (c) 2016 Magnus Norddahl +** +** This software is provided 'as-is', without any express or implied +** warranty. In no event will the authors be held liable for any damages +** arising from the use of this software. +** +** Permission is granted to anyone to use this software for any purpose, +** including commercial applications, and to alter it and redistribute it +** freely, subject to the following restrictions: +** +** 1. The origin of this software must not be misrepresented; you must not +** claim that you wrote the original software. If you use this software +** in a product, an acknowledgment in the product documentation would be +** appreciated but is not required. +** 2. Altered source versions must be plainly marked as such, and must not be +** misrepresented as being the original software. +** 3. This notice may not be removed or altered from any source distribution. +** +*/ + + +#ifndef __R_TRIANGLE__ +#define __R_TRIANGLE__ + +#include "r_draw.h" + +class FTexture; +struct ScreenTriangleDrawerArgs; + +struct TriVertex +{ + TriVertex() { } + TriVertex(float x, float y, float z, float w, float u, float v, float light) : x(x), y(y), z(z), w(w) { varying[0] = u; varying[1] = v; varying[2] = light; } + + enum { NumVarying = 3 }; + float x, y, z, w; + float varying[NumVarying]; +}; + +struct TriMatrix +{ + static TriMatrix null(); + static TriMatrix identity(); + static TriMatrix translate(float x, float y, float z); + static TriMatrix scale(float x, float y, float z); + static TriMatrix rotate(float angle, float x, float y, float z); + + TriVertex operator*(TriVertex v) const; + TriMatrix operator*(const TriMatrix &m) const; + + float matrix[16]; +}; + +class TriangleDrawer +{ +public: + static void draw(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, FTexture *texture); + static void fill(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, int solidcolor); + +private: + static void draw_any(const TriMatrix &objectToWorld, const TriVertex *vinput, int vcount, bool ccw, int clipleft, int clipright, const short *cliptop, const short *clipbottom, FTexture *texture, int solidcolor, void(*drawfunc)(const ScreenTriangleDrawerArgs *)); + static bool cullhalfspace(float clipdistance1, float clipdistance2, float &t1, float &t2); + static void clipedge(const TriVertex &v1, const TriVertex &v2, TriVertex *clippedvert, int &numclipvert); +}; + +struct ScreenTriangleDrawerArgs +{ + uint8_t *dest; + int pitch; + TriVertex *v1; + TriVertex *v2; + TriVertex *v3; + int clipleft; + int clipright; + const short *cliptop; + const short *clipbottom; + const uint8_t *texturePixels; + int textureWidth; + int textureHeight; + int solidcolor; +}; + +class ScreenTriangleDrawer +{ +public: + static void draw(const ScreenTriangleDrawerArgs *args); + static void fill(const ScreenTriangleDrawerArgs *args); + +private: + static float gradx(float x0, float y0, float x1, float y1, float x2, float y2, float c0, float c1, float c2); + static float grady(float x0, float y0, float x1, float y1, float x2, float y2, float c0, float c1, float c2); +}; + +#endif