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Altivec-optimized blitters!

Vast majority of this work is compliments of Bob Ippolito.

http://www.devolution.com/pipermail/sdl/2005-February/067466.html and many
 other posts.
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icculus committed Apr 17, 2005
1 parent d449d45 commit d3117b5d8cda961ccceff975a16e4e4f81ad4172
Showing with 1,501 additions and 26 deletions.
  1. +8 −6 configure.in
  2. +14 −0 src/video/SDL_blit.h
  3. +790 −2 src/video/SDL_blit_A.c
  4. +689 −18 src/video/SDL_blit_N.c
@@ -1839,17 +1839,18 @@ CheckAltivec()
{
AC_MSG_CHECKING(for GCC Altivec instruction support)
have_gcc_altivec=no
save_CFLAGS="${CFLAGS}"
CFLAGS="${CFLAGS} -DGCC_ALTIVEC -DUSE_ALTIVEC_BLITTERS -faltivec"
AC_TRY_COMPILE([
vector unsigned int vzero() {
return vec_splat_u32(0);
}
],[
asm volatile ("mtspr 256, %0\n\t"
"vand %%v0, %%v0, %%v0"
:
: "r" (-1));
],[
have_gcc_altivec=yes
])
if test x$have_gcc_altivec = xyes; then
CFLAGS="$CFLAGS -DGCC_ALTIVEC"
if test x$have_gcc_altivec = xno; then
CFLAGS="${save_CFLAGS}"
fi
AC_MSG_RESULT($have_gcc_altivec)
}
@@ -2564,6 +2565,7 @@ case "$target" in
CheckMacGL
CheckPTHREAD
CheckSIGACTION
CheckAltivec
# If either the audio or CD driver is used, add the AudioUnit framework
if test x$enable_audio = xyes -o x$enable_cdrom = xyes; then
SYSTEM_LIBS="$SYSTEM_LIBS -framework AudioToolbox -framework AudioUnit"
@@ -374,6 +374,20 @@ do { \
dB = (((sB-dB)*(A))>>8)+dB; \
} while(0)

/* Blend the RGB values of two pixels based on a source alpha value */
#define ACCURATE_ALPHA_BLEND(sR, sG, sB, sA, dR, dG, dB) \
do { \
unsigned tR, tG, tB, tA; \
tA = 255 - sA; \
tR = 1 + (sR * sA) + (dR * tA); \
dR = (tR + (tR >> 8)) >> 8; \
tG = 1 + (sG * sA) + (dG * tA); \
dG = (tG + (tG >> 8)) >> 8; \
tB = 1 + (sB * sA) + (dB * tA); \
dB = (tB + (tB >> 8)) >> 8; \
} while(0)


/* This is a very useful loop for optimizing blitters */
#if defined(_MSC_VER) && (_MSC_VER == 1300)
/* There's a bug in the Visual C++ 7 optimizer when compiling this code */

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