view docs/man3/SDL_ListModes.3 @ 1542:a8bf1aa21020

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.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 15 Mar 2006 15:39:29 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_ListModes" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_ListModes\- Returns a pointer to an array of available screen dimensions for the given format and video flags
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBSDL_Rect **\fBSDL_ListModes\fP\fR(\fBSDL_PixelFormat *format, Uint32 flags\fR);
.SH "DESCRIPTION"
.PP
Return a pointer to an array of available screen dimensions for the given format and video flags, sorted largest to smallest\&. Returns \fBNULL\fP if there are no dimensions available for a particular format, or \fB-1\fR if any dimension is okay for the given format\&.
.PP
If \fBformat\fR is \fBNULL\fP, the mode list will be for the format returned by \fISDL_GetVideoInfo()\fR->\fBvfmt\fR\&. The \fBflag\fR parameter is an OR\&'d combination of \fIsurface\fR flags\&. The flags are the same as those used \fI\fBSDL_SetVideoMode\fP\fR and they play a strong role in deciding what modes are valid\&. For instance, if you pass \fBSDL_HWSURFACE\fP as a flag only modes that support hardware video surfaces will be returned\&.
.SH "EXAMPLE"
.PP
.nf
\f(CWSDL_Rect **modes;
int i;
\&.
\&.
\&.

/* Get available fullscreen/hardware modes */
modes=SDL_ListModes(NULL, SDL_FULLSCREEN|SDL_HWSURFACE);

/* Check is there are any modes available */
if(modes == (SDL_Rect **)0){
  printf("No modes available!
");
  exit(-1);
}

/* Check if or resolution is restricted */
if(modes == (SDL_Rect **)-1){
  printf("All resolutions available\&.
");
}
else{
  /* Print valid modes */
  printf("Available Modes
");
  for(i=0;modes[i];++i)
    printf("  %d x %d
", modes[i]->w, modes[i]->h);
}
\&.
\&.\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_SetVideoMode\fP\fR, \fI\fBSDL_GetVideoInfo\fP\fR, \fI\fBSDL_Rect\fR\fR, \fI\fBSDL_PixelFormat\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01