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Date: Fri, 19 Nov 2004 06:23:53 -0800 (PST) From: Eric Wing Subject: OS X Mouse inversion problem fix (again) Here's yet another patch for the OS X mouse inversion problem. This should fix the problem once and for all. I know I've said this before, but *This time for sure!* :) If you recall, my last patch broke the non-OpenGL windowed code and caused the inversion to occur there instead. Max submitted a patch that partially reverted the changes back which included the os version hack which is currently the most recent CVS. Aaron Sullivan identified and reported to the mailing list the other day, that the last partial regression of the code broke OS X 10.2. Looking over the results, I'm thinking that I was slightly more successful than I thought at unifying the code. I think I was trying to unify the code base for OpenGL and non-OpenGL windowed modes for all versions of the OS. It looks like I failed at at unifying the OpenGL and non-OpenGL code, but I did succeed at unifying the OS versions. Thus, we no longer need the hack for the OS version checks. The partial regression still included an OS check which is what broke things for < 10.3. Attached is the patch for SDL_QuartzWM.m. It basically is a half-line change that removes one of the two checks that decides if the mouse coordinates need to be inverted, i.e: if (system_version >= 0x1030 && (SDL_VideoSurface->flags & SDL_OPENGL) ) becomes this: if(SDL_VideoSurface->flags & SDL_OPENGL) With Aaron's outstanding help, we have collectively tested: windowed OpenGL windowed non-OpenGL fullscreen OpenGL fullscreen non-OpenGL under OS X 10.2 (Jaguar), 10.3 (Panther), and 10.4 (Tiger). We don't have access to 10.0 or 10.1, but since the original problem didn't materialize until 10.3, I'm hopeful that testing 10.2 is sufficient. And now that the code is uniform, I'm also hoping we'll be safe moving forward to deal with future revisions of the OS with this issue.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 21 Nov 2004 00:57:47 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_AudioCVT" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_AudioCVT\- Audio Conversion Structure
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef struct{
  int needed;
  Uint16 src_format;
  Uint16 dest_format;
  double rate_incr;
  Uint8 *buf;
  int len;
  int len_cvt;
  int len_mult;
  double len_ratio;
  void (*filters[10])(struct SDL_AudioCVT *cvt, Uint16 format);
  int filter_index;
} SDL_AudioCVT;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBneeded\fR
Set to one if the conversion is possible
.TP 20
\fBsrc_format\fR
Audio format of the source
.TP 20
\fBdest_format\fR
Audio format of the destination
.TP 20
\fBrate_incr\fR
Rate conversion increment
.TP 20
\fBbuf\fR
Audio buffer
.TP 20
\fBlen\fR
Length of the original audio buffer in bytes
.TP 20
\fBlen_cvt\fR
Length of converted audio buffer in bytes (calculated)
.TP 20
\fBlen_mult\fR
\fBbuf\fR must be \fBlen\fR*\fBlen_mult\fR bytes in size(calculated)
.TP 20
\fBlen_ratio\fR
Final audio size is \fBlen\fR*\fBlen_ratio\fR
.TP 20
\fBfilters[10](\&.\&.)\fR
Pointers to functions needed for this conversion
.TP 20
\fBfilter_index\fR
Current conversion function
.SH "DESCRIPTION"
.PP
The \fBSDL_AudioCVT\fR is used to convert audio data between different formats\&. A \fBSDL_AudioCVT\fR structure is created with the \fI\fBSDL_BuildAudioCVT\fP\fR function, while the actual conversion is done by the \fI\fBSDL_ConvertAudio\fP\fR function\&.
.PP
Many of the fields in the \fBSDL_AudioCVT\fR structure should be considered private and their function will not be discussed here\&.
.IP "\fBUint8 *\fP\fBbuf\fR" 10This points to the audio data that will be used in the conversion\&. It is both the source and the destination, which means the converted audio data overwrites the original data\&. It also means that the converted data may be larger than the original data (if you were converting from 8-bit to 16-bit, for instance), so you must ensure \fBbuf\fR is large enough\&. See below\&.
.IP "\fBint\fP \fBlen\fR" 10This is the length of the original audio data in bytes\&.
.IP "\fBint\fP \fBlen_mult\fR" 10As explained above, the audio buffer needs to be big enough to store the converted data, which may be bigger than the original audio data\&. The length of \fBbuf\fR should be \fBlen\fR*\fBlen_mult\fR\&.
.IP "\fBdouble\fP \fBlen_ratio\fR" 10When you have finished converting your audio data, you need to know how much of your audio buffer is valid\&. \fBlen\fR*\fBlen_ratio\fR is the size of the converted audio data in bytes\&. This is very similar to \fBlen_mult\fR, however when the convert audio data is shorter than the original \fBlen_mult\fR would be 1\&. \fBlen_ratio\fR, on the other hand, would be a fractional number between 0 and 1\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_BuildAudioCVT\fP\fR, \fI\fBSDL_ConvertAudio\fP\fR, \fI\fBSDL_AudioSpec\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58