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_JoystickGetAxis" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_JoystickGetAxis\- Get the current state of an axis
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBSint16 \fBSDL_JoystickGetAxis\fP\fR(\fBSDL_Joystick *joystick, int axis\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_JoystickGetAxis\fP returns the current state of the given \fBaxis\fR on the given \fBjoystick\fR\&.
.PP
On most modern joysticks the X axis is usually represented by \fBaxis\fR 0 and the Y axis by \fBaxis\fR 1\&. The value returned by \fBSDL_JoystickGetAxis\fP is a signed integer (-32768 to 32768) representing the current position of the \fBaxis\fR, it maybe necessary to impose certain tolerances on these values to account for jitter\&. It is worth noting that some joysticks use axes 2 and 3 for extra buttons\&.
.SH "RETURN VALUE"
.PP
Returns a 16-bit signed integer representing the current position of the \fBaxis\fR\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWSint16 x_move, y_move;
SDL_Joystick *joy1;
\&.
\&.
x_move=SDL_JoystickGetAxis(joy1, 0);
y_move=SDL_JoystickGetAxis(joy1, 1);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_JoystickNumAxes\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00