dolphin/Source/Core/VideoBackends/Software/Rasterizer.cpp

496 lines
13 KiB
C++

// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
#include <algorithm>
#include "Common/Common.h"
#include "VideoBackends/Software/BPMemLoader.h"
#include "VideoBackends/Software/EfbInterface.h"
#include "VideoBackends/Software/HwRasterizer.h"
#include "VideoBackends/Software/NativeVertexFormat.h"
#include "VideoBackends/Software/Rasterizer.h"
#include "VideoBackends/Software/SWStatistics.h"
#include "VideoBackends/Software/SWVideoConfig.h"
#include "VideoBackends/Software/Tev.h"
#include "VideoBackends/Software/XFMemLoader.h"
#define BLOCK_SIZE 2
#define CLAMP(x, a, b) (x>b)?b:(x<a)?a:x
// returns approximation of log2(f) in s28.4
// results are close enough to use for LOD
static inline s32 FixedLog2(float f)
{
u32 *x = (u32*)&f;
s32 logInt = ((*x & 0x7F800000) >> 19) - 2032; // integer part
s32 logFract = (*x & 0x007fffff) >> 19; // approximate fractional part
return logInt + logFract;
}
namespace Rasterizer
{
static Slope ZSlope;
static Slope WSlope;
static Slope ColorSlopes[2][4];
static Slope TexSlopes[8][3];
static s32 vertex0X;
static s32 vertex0Y;
static float vertexOffsetX;
static float vertexOffsetY;
static s32 scissorLeft = 0;
static s32 scissorTop = 0;
static s32 scissorRight = 0;
static s32 scissorBottom = 0;
static Tev tev;
static RasterBlock rasterBlock;
void DoState(PointerWrap &p)
{
ZSlope.DoState(p);
WSlope.DoState(p);
for (auto& color_slopes_1d : ColorSlopes)
for (Slope& color_slope : color_slopes_1d)
color_slope.DoState(p);
for (auto& tex_slopes_1d : TexSlopes)
for (Slope& tex_slope : tex_slopes_1d)
tex_slope.DoState(p);
p.Do(vertex0X);
p.Do(vertex0Y);
p.Do(vertexOffsetX);
p.Do(vertexOffsetY);
p.Do(scissorLeft);
p.Do(scissorTop);
p.Do(scissorRight);
p.Do(scissorBottom);
tev.DoState(p);
p.Do(rasterBlock);
}
void Init()
{
tev.Init();
// Set initial z reference plane in the unlikely case that zfreeze is enabled when drawing the first primitive.
// TODO: This is just a guess!
ZSlope.dfdx = ZSlope.dfdy = 0.f;
ZSlope.f0 = 1.f;
}
inline int iround(float x)
{
int t;
t = (int)x;
if ((x - t) >= 0.5)
return t + 1;
return t;
}
void SetScissor()
{
int xoff = bpmem.scissorOffset.x * 2 - 342;
int yoff = bpmem.scissorOffset.y * 2 - 342;
scissorLeft = bpmem.scissorTL.x - xoff - 342;
if (scissorLeft < 0) scissorLeft = 0;
scissorTop = bpmem.scissorTL.y - yoff - 342;
if (scissorTop < 0) scissorTop = 0;
scissorRight = bpmem.scissorBR.x - xoff - 341;
if (scissorRight > EFB_WIDTH) scissorRight = EFB_WIDTH;
scissorBottom = bpmem.scissorBR.y - yoff - 341;
if (scissorBottom > EFB_HEIGHT) scissorBottom = EFB_HEIGHT;
}
void SetTevReg(int reg, int comp, bool konst, s16 color)
{
tev.SetRegColor(reg, comp, konst, color);
}
inline void Draw(s32 x, s32 y, s32 xi, s32 yi)
{
INCSTAT(swstats.thisFrame.rasterizedPixels);
float dx = vertexOffsetX + (float)(x - vertex0X);
float dy = vertexOffsetY + (float)(y - vertex0Y);
s32 z = (s32)ZSlope.GetValue(dx, dy);
if (z < 0 || z > 0x00ffffff)
return;
if (bpmem.UseEarlyDepthTest() && g_SWVideoConfig.bZComploc)
{
// TODO: Test if perf regs are incremented even if test is disabled
EfbInterface::IncPerfCounterQuadCount(PQ_ZCOMP_INPUT_ZCOMPLOC);
if (bpmem.zmode.testenable)
{
// early z
if (!EfbInterface::ZCompare(x, y, z))
return;
}
EfbInterface::IncPerfCounterQuadCount(PQ_ZCOMP_OUTPUT_ZCOMPLOC);
}
RasterBlockPixel& pixel = rasterBlock.Pixel[xi][yi];
tev.Position[0] = x;
tev.Position[1] = y;
tev.Position[2] = z;
// colors
for (unsigned int i = 0; i < bpmem.genMode.numcolchans; i++)
{
for (int comp = 0; comp < 4; comp++)
{
u16 color = (u16)ColorSlopes[i][comp].GetValue(dx, dy);
// clamp color value to 0
u16 mask = ~(color >> 8);
tev.Color[i][comp] = color & mask;
}
}
// tex coords
for (unsigned int i = 0; i < bpmem.genMode.numtexgens; i++)
{
// multiply by 128 because TEV stores UVs as s17.7
tev.Uv[i].s = (s32)(pixel.Uv[i][0] * 128);
tev.Uv[i].t = (s32)(pixel.Uv[i][1] * 128);
}
for (unsigned int i = 0; i < bpmem.genMode.numindstages; i++)
{
tev.IndirectLod[i] = rasterBlock.IndirectLod[i];
tev.IndirectLinear[i] = rasterBlock.IndirectLinear[i];
}
for (unsigned int i = 0; i <= bpmem.genMode.numtevstages; i++)
{
tev.TextureLod[i] = rasterBlock.TextureLod[i];
tev.TextureLinear[i] = rasterBlock.TextureLinear[i];
}
tev.Draw();
}
static void InitTriangle(float X1, float Y1, s32 xi, s32 yi)
{
vertex0X = xi;
vertex0Y = yi;
// adjust a little less than 0.5
const float adjust = 0.495f;
vertexOffsetX = ((float)xi - X1) + adjust;
vertexOffsetY = ((float)yi - Y1) + adjust;
}
static void InitSlope(Slope *slope, float f1, float f2, float f3, float DX31, float DX12, float DY12, float DY31)
{
float DF31 = f3 - f1;
float DF21 = f2 - f1;
float a = DF31 * -DY12 - DF21 * DY31;
float b = DX31 * DF21 + DX12 * DF31;
float c = -DX12 * DY31 - DX31 * -DY12;
slope->dfdx = -a / c;
slope->dfdy = -b / c;
slope->f0 = f1;
}
inline void CalculateLOD(s32 &lod, bool &linear, u32 texmap, u32 texcoord)
{
FourTexUnits& texUnit = bpmem.tex[(texmap >> 2) & 1];
u8 subTexmap = texmap & 3;
// LOD calculation requires data from the texture mode for bias, etc.
// it does not seem to use the actual texture size
TexMode0& tm0 = texUnit.texMode0[subTexmap];
TexMode1& tm1 = texUnit.texMode1[subTexmap];
float sDelta, tDelta;
if (tm0.diag_lod)
{
float *uv0 = rasterBlock.Pixel[0][0].Uv[texcoord];
float *uv1 = rasterBlock.Pixel[1][1].Uv[texcoord];
sDelta = fabsf(uv0[0] - uv1[0]);
tDelta = fabsf(uv0[1] - uv1[1]);
}
else
{
float *uv0 = rasterBlock.Pixel[0][0].Uv[texcoord];
float *uv1 = rasterBlock.Pixel[1][0].Uv[texcoord];
float *uv2 = rasterBlock.Pixel[0][1].Uv[texcoord];
sDelta = std::max(fabsf(uv0[0] - uv1[0]), fabsf(uv0[0] - uv2[0]));
tDelta = std::max(fabsf(uv0[1] - uv1[1]), fabsf(uv0[1] - uv2[1]));
}
// get LOD in s28.4
lod = FixedLog2(std::max(sDelta, tDelta));
// bias is s2.5
int bias = tm0.lod_bias;
bias >>= 1;
lod += bias;
linear = ((lod > 0 && (tm0.min_filter & 4)) || (lod <= 0 && tm0.mag_filter));
// order of checks matters
// should be:
// if lod > max then max
// else if lod < min then min
lod = CLAMP(lod, (s32)tm1.min_lod, (s32)tm1.max_lod);
}
static void BuildBlock(s32 blockX, s32 blockY)
{
for (s32 yi = 0; yi < BLOCK_SIZE; yi++)
{
for (s32 xi = 0; xi < BLOCK_SIZE; xi++)
{
RasterBlockPixel& pixel = rasterBlock.Pixel[xi][yi];
float dx = vertexOffsetX + (float)(xi + blockX - vertex0X);
float dy = vertexOffsetY + (float)(yi + blockY - vertex0Y);
float invW = 1.0f / WSlope.GetValue(dx, dy);
pixel.InvW = invW;
// tex coords
for (unsigned int i = 0; i < bpmem.genMode.numtexgens; i++)
{
float projection = invW;
if (xfmem.texMtxInfo[i].projection)
{
float q = TexSlopes[i][2].GetValue(dx, dy) * invW;
if (q != 0.0f)
projection = invW / q;
}
pixel.Uv[i][0] = TexSlopes[i][0].GetValue(dx, dy) * projection;
pixel.Uv[i][1] = TexSlopes[i][1].GetValue(dx, dy) * projection;
}
}
}
u32 indref = bpmem.tevindref.hex;
for (unsigned int i = 0; i < bpmem.genMode.numindstages; i++)
{
u32 texmap = indref & 3;
indref >>= 3;
u32 texcoord = indref & 3;
indref >>= 3;
CalculateLOD(rasterBlock.IndirectLod[i], rasterBlock.IndirectLinear[i], texmap, texcoord);
}
for (unsigned int i = 0; i <= bpmem.genMode.numtevstages; i++)
{
int stageOdd = i&1;
TwoTevStageOrders &order = bpmem.tevorders[i >> 1];
if (order.getEnable(stageOdd))
{
u32 texmap = order.getTexMap(stageOdd);
u32 texcoord = order.getTexCoord(stageOdd);
CalculateLOD(rasterBlock.TextureLod[i], rasterBlock.TextureLinear[i], texmap, texcoord);
}
}
}
void DrawTriangleFrontFace(OutputVertexData *v0, OutputVertexData *v1, OutputVertexData *v2)
{
INCSTAT(swstats.thisFrame.numTrianglesDrawn);
if (g_SWVideoConfig.bHwRasterizer)
{
HwRasterizer::DrawTriangleFrontFace(v0, v1, v2);
return;
}
// adapted from http://devmaster.net/posts/6145/advanced-rasterization
// 28.4 fixed-pou32 coordinates. rounded to nearest and adjusted to match hardware output
// could also take floor and adjust -8
const s32 Y1 = iround(16.0f * v0->screenPosition[1]) - 9;
const s32 Y2 = iround(16.0f * v1->screenPosition[1]) - 9;
const s32 Y3 = iround(16.0f * v2->screenPosition[1]) - 9;
const s32 X1 = iround(16.0f * v0->screenPosition[0]) - 9;
const s32 X2 = iround(16.0f * v1->screenPosition[0]) - 9;
const s32 X3 = iround(16.0f * v2->screenPosition[0]) - 9;
// Deltas
const s32 DX12 = X1 - X2;
const s32 DX23 = X2 - X3;
const s32 DX31 = X3 - X1;
const s32 DY12 = Y1 - Y2;
const s32 DY23 = Y2 - Y3;
const s32 DY31 = Y3 - Y1;
// Fixed-pos32 deltas
const s32 FDX12 = DX12 << 4;
const s32 FDX23 = DX23 << 4;
const s32 FDX31 = DX31 << 4;
const s32 FDY12 = DY12 << 4;
const s32 FDY23 = DY23 << 4;
const s32 FDY31 = DY31 << 4;
// Bounding rectangle
s32 minx = (std::min(std::min(X1, X2), X3) + 0xF) >> 4;
s32 maxx = (std::max(std::max(X1, X2), X3) + 0xF) >> 4;
s32 miny = (std::min(std::min(Y1, Y2), Y3) + 0xF) >> 4;
s32 maxy = (std::max(std::max(Y1, Y2), Y3) + 0xF) >> 4;
// scissor
minx = std::max(minx, scissorLeft);
maxx = std::min(maxx, scissorRight);
miny = std::max(miny, scissorTop);
maxy = std::min(maxy, scissorBottom);
if (minx >= maxx || miny >= maxy)
return;
// Setup slopes
float fltx1 = v0->screenPosition.x;
float flty1 = v0->screenPosition.y;
float fltdx31 = v2->screenPosition.x - fltx1;
float fltdx12 = fltx1 - v1->screenPosition.x;
float fltdy12 = flty1 - v1->screenPosition.y;
float fltdy31 = v2->screenPosition.y - flty1;
InitTriangle(fltx1, flty1, (X1 + 0xF) >> 4, (Y1 + 0xF) >> 4);
float w[3] = { 1.0f / v0->projectedPosition.w, 1.0f / v1->projectedPosition.w, 1.0f / v2->projectedPosition.w };
InitSlope(&WSlope, w[0], w[1], w[2], fltdx31, fltdx12, fltdy12, fltdy31);
// TODO: The zfreeze emulation is not quite correct, yet!
// Many things might prevent us from reaching this line (culling, clipping, scissoring).
// However, the zslope is always guaranteed to be calculated unless all vertices are trivially rejected during clipping!
// We're currently sloppy at this since we abort early if any of the culling/clipping/scissoring tests fail.
if (!bpmem.genMode.zfreeze || !g_SWVideoConfig.bZFreeze)
InitSlope(&ZSlope, v0->screenPosition[2], v1->screenPosition[2], v2->screenPosition[2], fltdx31, fltdx12, fltdy12, fltdy31);
for (unsigned int i = 0; i < bpmem.genMode.numcolchans; i++)
{
for (int comp = 0; comp < 4; comp++)
InitSlope(&ColorSlopes[i][comp], v0->color[i][comp], v1->color[i][comp], v2->color[i][comp], fltdx31, fltdx12, fltdy12, fltdy31);
}
for (unsigned int i = 0; i < bpmem.genMode.numtexgens; i++)
{
for (int comp = 0; comp < 3; comp++)
InitSlope(&TexSlopes[i][comp], v0->texCoords[i][comp] * w[0], v1->texCoords[i][comp] * w[1], v2->texCoords[i][comp] * w[2], fltdx31, fltdx12, fltdy12, fltdy31);
}
// Start in corner of 8x8 block
minx &= ~(BLOCK_SIZE - 1);
miny &= ~(BLOCK_SIZE - 1);
// Half-edge constants
s32 C1 = DY12 * X1 - DX12 * Y1;
s32 C2 = DY23 * X2 - DX23 * Y2;
s32 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 (s32 y = miny; y < maxy; y += BLOCK_SIZE)
{
for (s32 x = minx; x < maxx; x += BLOCK_SIZE)
{
// Corners of block
s32 x0 = x << 4;
s32 x1 = (x + BLOCK_SIZE - 1) << 4;
s32 y0 = y << 4;
s32 y1 = (y + BLOCK_SIZE - 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;
BuildBlock(x, y);
// Accept whole block when totally covered
if (a == 0xF && b == 0xF && c == 0xF)
{
for (s32 iy = 0; iy < BLOCK_SIZE; iy++)
{
for (s32 ix = 0; ix < BLOCK_SIZE; ix++)
{
Draw(x + ix, y + iy, ix, iy);
}
}
}
else // Partially covered block
{
s32 CY1 = C1 + DX12 * y0 - DY12 * x0;
s32 CY2 = C2 + DX23 * y0 - DY23 * x0;
s32 CY3 = C3 + DX31 * y0 - DY31 * x0;
for (s32 iy = 0; iy < BLOCK_SIZE; iy++)
{
s32 CX1 = CY1;
s32 CX2 = CY2;
s32 CX3 = CY3;
for (s32 ix = 0; ix < BLOCK_SIZE; ix++)
{
if (CX1 > 0 && CX2 > 0 && CX3 > 0)
{
Draw(x + ix, y + iy, ix, iy);
}
CX1 -= FDY12;
CX2 -= FDY23;
CX3 -= FDY31;
}
CY1 += FDX12;
CY2 += FDX23;
CY3 += FDX31;
}
}
}
}
}
}