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Fixed bug #61 Date: Mon, 24 Feb 2003 13:35:11 +0800 From: "Leonidas" Subject: [SDL] Re: Trigger mouse wheel event -- not in X-environment I have looked into the codes for the IMPS/2 mouse wheel mode of fbcon driver. But I found something weird. Here's the original codes to set a mouse device into IMPS/2 mode in libSDL. In the file src/video/fbcon/SDL_fbevents.c In function static int set_imps2_mode(int fd) ... Uint8 set_imps2[] = {0xf3, 200, 0xf3, 100, 0xf3, 80}; Uint8 reset = 0xff; fd_set fdset; struct timeval tv; int retval = 0; // Set mouse device fd into IMPS/2 mode if ( write(fd, &set_imps2, sizeof(set_imps2)) == sizeof(set_imps2) ) { // ??? then RESET it..??? if (write(fd, &reset, sizeof (reset)) == sizeof (reset) ) { retval = 1; } } ........... Since it sets IMPS/2 mode then reset it, so you will never get a mouse into IMPS/2 mode to use its wheel. What I did to make the wheel usable is remove the RESET codes. .... if ( write(fd, &set_imps2, sizeof(set_imps2)) == sizeof(set_imps2) ) { /* if (write(fd, &reset, sizeof (reset)) == sizeof (reset) ) { } */ retval = 1; } .... And in FB_OpenMouse(_THIS) Make the device /dev/psaux to be setted into imps2 mode such that it can be detected its a imps/2 mouse or not. (my mouse device is on ps2, but the codes only set /dev/input/mice device originally) Then I have done, I can use the mouse wheel when SDL uses frame buff driver. I dont exactly know I did right or wrong, I just change it for my usuage. Correct me please, if I did something wrong. Best regards, Li Tsung Lin IAP Product Dept. Engineer EeRise Corp. (Image Processing System, Computer Vision System) Hsin Tien, Taipei Hsien, Taiwan, R.O.C.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 22 Mar 2006 07:22:40 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
><META
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><DIV
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><H1
><A
NAME="AUDIO"
></A
>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
></DL
></DIV
><P
>Sound on the computer is translated from waves that you hear into a series of 
values, or samples, each representing the amplitude of the wave.  When these
samples are sent in a stream to a sound card, an approximation of the original
wave can be recreated.  The more bits used to represent the amplitude, and the
greater frequency these samples are gathered, the closer the approximated
sound is to the original, and the better the quality of sound.</P
><P
>This library supports both 8 and 16 bit signed and unsigned sound samples,
at frequencies ranging from 11025 Hz to 44100 Hz, depending on the 
underlying hardware.  If the hardware doesn't support the desired audio
format or frequency, it can be emulated if desired (See 
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio()</TT
></A
>)</P
><P
>A commonly supported audio format is 16 bits per sample at 22050 Hz.</P
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