dolphin/Source/Plugins/Plugin_VideoSoftware/Src/TextureSampler.cpp

209 lines
6.1 KiB
C++

// Copyright (C) 2003-2009 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#include "TextureSampler.h"
#include "main.h"
#include "BPMemLoader.h"
#include "../../../Core/VideoCommon/Src/TextureDecoder.h"
#include <cmath>
#define ALLOW_MIPMAP 1
namespace TextureSampler
{
inline void WrapCoord(int &coord, int wrapMode, int imageSize)
{
switch (wrapMode)
{
case 0: // clamp
coord = (coord>imageSize)?imageSize:(coord<0)?0:coord;
break;
case 1: // wrap
coord = coord % (imageSize + 1);
coord = (coord<0)?imageSize+coord:coord;
break;
case 2: // mirror
{
int sizePlus1 = imageSize + 1;
int div = coord / sizePlus1;
coord = coord - (div * sizePlus1);
coord = (coord<0)?-coord:coord;
coord = (div&1)?imageSize - coord:coord;
}
break;
}
}
inline void SetTexel(u8 *inTexel, u32 *outTexel, u32 fract)
{
outTexel[0] = inTexel[0] * fract;
outTexel[1] = inTexel[1] * fract;
outTexel[2] = inTexel[2] * fract;
outTexel[3] = inTexel[3] * fract;
}
inline void AddTexel(u8 *inTexel, u32 *outTexel, u32 fract)
{
outTexel[0] += inTexel[0] * fract;
outTexel[1] += inTexel[1] * fract;
outTexel[2] += inTexel[2] * fract;
outTexel[3] += inTexel[3] * fract;
}
void Sample(s32 s, s32 t, s32 lod, bool linear, u8 texmap, u8 *sample)
{
int baseMip = 0;
bool mipLinear = false;
#if (ALLOW_MIPMAP)
FourTexUnits& texUnit = bpmem.tex[(texmap >> 2) & 1];
TexMode0& tm0 = texUnit.texMode0[texmap & 3];
s32 lodFract = lod & 0xf;
if (lod > 0 && tm0.min_filter & 3)
{
// use mipmap
baseMip = lod >> 4;
mipLinear = (lodFract && tm0.min_filter & 2);
// if using nearest mip filter and lodFract >= 0.5 round up to next mip
baseMip += (lodFract >> 3) & (tm0.min_filter & 1);
}
if (mipLinear)
{
u8 sampledTex[4];
u32 texel[4];
SampleMip(s, t, baseMip, linear, texmap, sampledTex);
SetTexel(sampledTex, texel, (16 - lodFract));
SampleMip(s, t, baseMip + 1, linear, texmap, sampledTex);
AddTexel(sampledTex, texel, lodFract);
sample[0] = (u8)(texel[0] >> 4);
sample[1] = (u8)(texel[1] >> 4);
sample[2] = (u8)(texel[2] >> 4);
sample[3] = (u8)(texel[3] >> 4);
}
else
#endif
{
SampleMip(s, t, baseMip, linear, texmap, sample);
}
}
void SampleMip(s32 s, s32 t, s32 mip, bool linear, u8 texmap, u8 *sample)
{
FourTexUnits& texUnit = bpmem.tex[(texmap >> 2) & 1];
u8 subTexmap = texmap & 3;
TexMode0& tm0 = texUnit.texMode0[subTexmap];
TexImage0& ti0 = texUnit.texImage0[subTexmap];
TexTLUT& texTlut = texUnit.texTlut[subTexmap];
u32 imageBase = texUnit.texImage3[subTexmap].image_base << 5;
u8 *imageSrc = g_VideoInitialize.pGetMemoryPointer(imageBase);
int imageWidth = ti0.width;
int imageHeight = ti0.height;
int tlutAddress = texTlut.tmem_offset << 9;
// reduce sample location and texture size to mip level
// move texture pointer to mip location
if (mip)
{
int mipWidth = imageWidth + 1;
int mipHeight = imageHeight + 1;
int fmtWidth = TexDecoder_GetBlockWidthInTexels(ti0.format);
int fmtHeight = TexDecoder_GetBlockHeightInTexels(ti0.format);
int fmtDepth = TexDecoder_GetTexelSizeInNibbles(ti0.format);
imageWidth >>= mip;
imageHeight >>= mip;
s >>= mip;
t >>= mip;
while (mip)
{
mipWidth = max(mipWidth, fmtWidth);
mipHeight = max(mipHeight, fmtHeight);
u32 size = (mipWidth * mipHeight * fmtDepth) >> 1;
imageSrc += size;
mipWidth >>= 1;
mipHeight >>= 1;
mip--;
}
}
// integer part of sample location
int imageS = s >> 7;
int imageT = t >> 7;
if (linear)
{
// linear sampling
int imageSPlus1 = imageS + 1;
int fractS = s & 0x7f;
int imageTPlus1 = imageT + 1;
int fractT = t & 0x7f;
u8 sampledTex[4];
u32 texel[4];
WrapCoord(imageS, tm0.wrap_s, imageWidth);
WrapCoord(imageT, tm0.wrap_t, imageHeight);
WrapCoord(imageSPlus1, tm0.wrap_s, imageWidth);
WrapCoord(imageTPlus1, tm0.wrap_t, imageHeight);
TexDecoder_DecodeTexel(sampledTex, imageSrc, imageS, imageT, imageWidth, ti0.format, tlutAddress, texTlut.tlut_format);
SetTexel(sampledTex, texel, (128 - fractS) * (128 - fractT));
TexDecoder_DecodeTexel(sampledTex, imageSrc, imageSPlus1, imageT, imageWidth, ti0.format, tlutAddress, texTlut.tlut_format);
AddTexel(sampledTex, texel, (fractS) * (128 - fractT));
TexDecoder_DecodeTexel(sampledTex, imageSrc, imageS, imageTPlus1, imageWidth, ti0.format, tlutAddress, texTlut.tlut_format);
AddTexel(sampledTex, texel, (128 - fractS) * (fractT));
TexDecoder_DecodeTexel(sampledTex, imageSrc, imageSPlus1, imageTPlus1, imageWidth, ti0.format, tlutAddress, texTlut.tlut_format);
AddTexel(sampledTex, texel, (fractS) * (fractT));
sample[0] = (u8)(texel[0] >> 14);
sample[1] = (u8)(texel[1] >> 14);
sample[2] = (u8)(texel[2] >> 14);
sample[3] = (u8)(texel[3] >> 14);
}
else
{
// nearest neighbor sampling
WrapCoord(imageS, tm0.wrap_s, imageWidth);
WrapCoord(imageT, tm0.wrap_t, imageHeight);
TexDecoder_DecodeTexel(sample, imageSrc, imageS, imageT, imageWidth, ti0.format, tlutAddress, texTlut.tlut_format);
}
}
}