libretro/beetle-psx-libretro
1
0
Fork 0
mirror of https://github.com/libretro/beetle-psx-libretro.git synced 2024-11-27 19:00:35 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Create PlotPixelBlend - cut down on code duplication

Browse Source
This commit is contained in:
twinaphex 2016-02-09 21:40:50 +01:00
parent 9acc59e0a2
commit a63f6af6a6
2 changed files with 46 additions and 90 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
mednafen/psx/gpu.h
View File

@ -338,6 +338,9 @@ class PS_GPU
uint32 ReadData(void);
void SoftReset(void);
template<int BlendMode>
void PlotPixelBlend(uint16_t bg_pix, uint16_t *fore_pix);
template<int BlendMode, bool MaskEval_TA, bool textured>
void PlotPixel(int32 x, int32 y, uint16 pix);

133
mednafen/psx/gpu_common.cpp
View File

@ -1,3 +1,41 @@
template<int BlendMode>
INLINE void PS_GPU::PlotPixelBlend(uint16_t bg_pix, uint16_t *fore_pix)
{
uint32_t sum, carry, diff, borrow;
// Efficient 15bpp pixel math algorithms from blargg
switch(BlendMode)
{
case BLEND_MODE_AVERAGE:
bg_pix |= 0x8000;
*fore_pix = ((*fore_pix + bg_pix) - ((*fore_pix ^ bg_pix) & 0x0421)) >> 1;
break;
case BLEND_MODE_ADD:
bg_pix &= ~0x8000;
sum = *fore_pix + bg_pix;
carry = (sum - ((*fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
*fore_pix = (sum - carry) | (carry - (carry >> 5));
break;
case BLEND_MODE_SUBTRACT:
bg_pix |= 0x8000;
*fore_pix &= ~0x8000;
diff = bg_pix - *fore_pix + 0x108420;
borrow = (diff - ((bg_pix ^ *fore_pix) & 0x108420)) & 0x108420;
*fore_pix = (diff - borrow) & (borrow - (borrow >> 5));
break;
case BLEND_MODE_ADD_FOURTH:
bg_pix &= ~0x8000;
*fore_pix = ((*fore_pix >> 2) & 0x1CE7) | 0x8000;
sum = *fore_pix + bg_pix;
carry = (sum - ((*fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
*fore_pix = (sum - carry) | (carry - (carry >> 5));
break;
}
}
template<int BlendMode, bool MaskEval_TA, bool textured>
INLINE void PS_GPU::PlotPixel(int32_t x, int32_t y, uint16_t fore_pix)
{
@ -6,51 +44,9 @@ INLINE void PS_GPU::PlotPixel(int32_t x, int32_t y, uint16_t fore_pix)
if(BlendMode >= 0 && (fore_pix & 0x8000))
{
uint16 bg_pix = vram_fetch(x, y); // Don't use bg_pix for mask evaluation, it's modified in blending code paths.
// Efficient 15bpp pixel math algorithms from blargg
switch(BlendMode)
{
case BLEND_MODE_AVERAGE:
bg_pix |= 0x8000;
fore_pix = ((fore_pix + bg_pix) - ((fore_pix ^ bg_pix) & 0x0421)) >> 1;
break;
case BLEND_MODE_ADD:
{
bg_pix &= ~0x8000;
uint32_t sum = fore_pix + bg_pix;
uint32_t carry = (sum - ((fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
fore_pix = (sum - carry) | (carry - (carry >> 5));
}
break;
case BLEND_MODE_SUBTRACT:
{
bg_pix |= 0x8000;
fore_pix &= ~0x8000;
uint32_t diff = bg_pix - fore_pix + 0x108420;
uint32_t borrow = (diff - ((bg_pix ^ fore_pix) & 0x108420)) & 0x108420;
fore_pix = (diff - borrow) & (borrow - (borrow >> 5));
}
break;
case BLEND_MODE_ADD_FOURTH:
{
bg_pix &= ~0x8000;
fore_pix = ((fore_pix >> 2) & 0x1CE7) | 0x8000;
uint32_t sum = fore_pix + bg_pix;
uint32_t carry = (sum - ((fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
fore_pix = (sum - carry) | (carry - (carry >> 5));
}
break;
}
// Don't use bg_pix for mask evaluation, it's modified in blending code paths.
uint16_t bg_pix = vram_fetch(x, y);
PlotPixelBlend<BlendMode>(bg_pix, &fore_pix);
}
if(!MaskEval_TA || !(vram_fetch(x, y) & 0x8000))
@ -66,51 +62,8 @@ INLINE void PS_GPU::PlotNativePixel(int32_t x, int32_t y, uint16_t fore_pix)
if(BlendMode >= 0 && (fore_pix & 0x8000))
{
uint16 bg_pix = texel_fetch(x, y); // Don't use bg_pix for mask evaluation, it's modified in blending code paths.
// Efficient 15bpp pixel math algorithms from blargg
switch(BlendMode)
{
case BLEND_MODE_AVERAGE:
bg_pix |= 0x8000;
fore_pix = ((fore_pix + bg_pix) - ((fore_pix ^ bg_pix) & 0x0421)) >> 1;
break;
case BLEND_MODE_ADD:
{
bg_pix &= ~0x8000;
uint32_t sum = fore_pix + bg_pix;
uint32_t carry = (sum - ((fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
fore_pix = (sum - carry) | (carry - (carry >> 5));
}
break;
case BLEND_MODE_SUBTRACT:
{
bg_pix |= 0x8000;
fore_pix &= ~0x8000;
uint32_t diff = bg_pix - fore_pix + 0x108420;
uint32_t borrow = (diff - ((bg_pix ^ fore_pix) & 0x108420)) & 0x108420;
fore_pix = (diff - borrow) & (borrow - (borrow >> 5));
}
break;
case BLEND_MODE_ADD_FOURTH:
{
bg_pix &= ~0x8000;
fore_pix = ((fore_pix >> 2) & 0x1CE7) | 0x8000;
uint32_t sum = fore_pix + bg_pix;
uint32_t carry = (sum - ((fore_pix ^ bg_pix) & 0x8421)) & 0x8420;
fore_pix = (sum - carry) | (carry - (carry >> 5));
}
break;
}
uint16_t bg_pix = texel_fetch(x, y); // Don't use bg_pix for mask evaluation, it's modified in blending code paths.
PlotPixelBlend<BlendMode>(bg_pix, &fore_pix);
}
if(!MaskEval_TA || !(texel_fetch(x, y) & 0x8000))