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_InitSubSystem" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_InitSubSystem\- Initialize subsystems
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBint \fBSDL_InitSubSystem\fP\fR(\fBUint32 flags\fR);
.SH "DESCRIPTION"
.PP
After SDL has been initialized with \fI\fBSDL_Init\fP\fR you may initialize uninitialized subsystems with \fBSDL_InitSubSystem\fP\&. The \fBflags\fR parameter is the same as that used in \fI\fBSDL_Init\fP\fR\&.
.SH "EXAMPLES"
.PP
.nf
\f(CW/* Seperating Joystick and Video initialization\&. */
SDL_Init(SDL_INIT_VIDEO);
\&.
\&.
SDL_SetVideoMode(640, 480, 16, SDL_DOUBLEBUF|SDL_FULLSCREEN);
\&.
/* Do Some Video stuff */
\&.
\&.
/* Initialize the joystick subsystem */
SDL_InitSubSystem(SDL_INIT_JOYSTICK);

/* Do some stuff with video and joystick */
\&.
\&.
\&.
/* Shut them both down */
SDL_Quit();\fR
.fi
.PP
.SH "RETURN VALUE"
.PP
Returns \fB-1\fR on an error or \fB0\fR on success\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_Init\fP\fR, \fI\fBSDL_Quit\fP\fR, \fI\fBSDL_QuitSubSystem\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00