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- minor, but very effective optimization for R_DrawSpanMasked: Do not store the texel value in a byte. Store it in a local int variable. This allows the compiler to read it with a zero extending instruction instead of using a byte reading instruction and then later having it to convert to an int anyway. This removes one instruction from the loop which results in a 10% performance increase on 32 bit.

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This commit is contained in:
Christoph Oelckers 2016-12-04 19:32:54 +01:00
parent c9caaf08c8
commit f4454d2e00
1 changed files with 5 additions and 5 deletions
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10
src/r_draw.cpp
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@ -1037,7 +1037,7 @@ void R_SetupSpanBits(FTexture *tex)
{
ds_xbits--;
}
if ((1 << ds_ybits) > tex->GetHeight())
if ((1 << ds_ybits) > tex->GetHeight())
{
ds_ybits--;
}
@ -1048,7 +1048,7 @@ void R_SetupSpanBits(FTexture *tex)
//
// Draws the actual span.
#ifndef X86_ASM
//#ifndef X86_ASM
void R_DrawSpanP_C (void)
{
dsfixed_t xfrac;
@ -1147,7 +1147,7 @@ void R_DrawSpanMaskedP_C (void)
// 64x64 is the most common case by far, so special case it.
do
{
BYTE texdata;
int texdata;
spot = ((xfrac>>(32-6-6))&(63*64)) + (yfrac>>(32-6));
texdata = source[spot];
@ -1167,7 +1167,7 @@ void R_DrawSpanMaskedP_C (void)
int xmask = ((1 << ds_xbits) - 1) << ds_ybits;
do
{
BYTE texdata;
int texdata;
spot = ((xfrac >> xshift) & xmask) + (yfrac >> yshift);
texdata = source[spot];
@ -1181,7 +1181,7 @@ void R_DrawSpanMaskedP_C (void)
} while (--count);
}
}
#endif
//#endif
void R_DrawSpanTranslucent (void)
{