Fixed bug #15 SDL_blit_A.mmx-speed.patch.txt -- Speed improvements and a bugfix for the current GCC inline mmx asm code: - Changed some ops and removed some resulting useless ones. - Added some instruction parallelism (some gain) The resulting speed on my Xeon improved upto 35% depending on the function (measured in fps). - Fixed a bug where BlitRGBtoRGBSurfaceAlphaMMX() was setting the alpha component on the destination surfaces (to opaque-alpha) even when the surface had none. SDL_blit_A.mmx-msvc.patch.txt -- MSVC mmx intrinsics version of the same GCC asm code. MSVC compiler tries to parallelize the code and to avoid register stalls, but does not always do a very good job. Per-surface blending MSVC functions run quite a bit faster than their pure-asm counterparts (upto 55% faster for 16bit ones), but the per-pixel blending runs somewhat slower than asm. - BlitRGBtoRGBSurfaceAlphaMMX and BlitRGBtoRGBPixelAlphaMMX (and all variants) can now also handle formats other than (A)RGB8888. Formats like RGBA8888 and some quite exotic ones are allowed -- like RAGB8888, or actually anything having channels aligned on 8bit boundary and full 8bit alpha (for per-pixel alpha blending). The performance cost of this change is virtually 0 for per-surface alpha blending (no extra ops inside the loop) and a single non-MMX op inside the loop for per-pixel blending. In testing, the per-pixel alpha blending takes a ~2% performance hit, but it still runs much faster than the current code in CVS. If necessary, a separate function with this functionality can be made. This code requires Processor Pack for VC6.

.TH "SDL_WasInit" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_WasInit\- Check which subsystems are initialized
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBUint32 \fBSDL_WasInit\fP\fR(\fBUint32 flags\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_WasInit\fP allows you to see which SDL subsytems have been \fIinitialized\fR\&. \fBflags\fR is a bitwise OR\&'d combination of the subsystems you wish to check (see \fI\fBSDL_Init\fP\fR for a list of subsystem flags)\&.
.SH "RETURN VALUE"
.PP
\fBSDL_WasInit\fP returns a bitwised OR\&'d combination of the initialized subsystems\&.
.SH "EXAMPLES"
.PP
.nf
\f(CW
/* Here are several ways you can use SDL_WasInit() */

/* Get init data on all the subsystems */
Uint32 subsystem_init;

subsystem_init=SDL_WasInit(SDL_INIT_EVERYTHING);

if(subsystem_init&SDL_INIT_VIDEO)
  printf("Video is initialized\&.
");
else
  printf("Video is not initialized\&.
");



/* Just check for one specfic subsystem */

if(SDL_WasInit(SDL_INIT_VIDEO)!=0)
  printf("Video is initialized\&.
");
else
  printf("Video is not initialized\&.
");




/* Check for two subsystems */

Uint32 subsystem_mask=SDL_INIT_VIDEO|SDL_INIT_AUDIO;

if(SDL_WasInit(subsystem_mask)==subsystem_mask)
  printf("Video and Audio initialized\&.
");
else
  printf("Video and Audio not initialized\&.
");
\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_Init\fP\fR, \fI\fBSDL_Subsystem\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00