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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
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>SDL_MixAudio</TITLE
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>SDL_MixAudio</H1
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><H2
>Name</H2
>SDL_MixAudio&nbsp;--&nbsp;Mix audio data</DIV
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>Synopsis</H2
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void <B
CLASS="FSFUNC"
>SDL_MixAudio</B
></CODE
>(Uint8 *dst, Uint8 *src, Uint32 len, int volume);</CODE
></P
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></DIV
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><A
NAME="AEN7117"
></A
><H2
>Description</H2
><P
>This function takes two audio buffers of <TT
CLASS="PARAMETER"
><I
>len</I
></TT
> bytes each
of the playing audio format and mixes them, performing addition, volume
adjustment, and overflow clipping. The <TT
CLASS="PARAMETER"
><I
>volume</I
></TT
> ranges
from 0 to <TT
CLASS="LITERAL"
>SDL_MIX_MAXVOLUME</TT
> and should be set to the maximum
value for full audio volume. Note this does not change hardware volume. This is
provided for convenience -- you can mix your own audio data.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>Do not use this function for mixing together more than two streams of sample
data. The output from repeated application of this function may be distorted
by clipping, because there is no accumulator with greater range than the
input (not to mention this being an inefficient way of doing it).
Use mixing functions from SDL_mixer, OpenAL, or write your own mixer instead.</P
></BLOCKQUOTE
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>See Also</H2
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><TT
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>SDL_OpenAudio</TT
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