Date: Fri, 05 Mar 2004 16:08:01 +0000
From: Alan Swanson
Subject: Re: [SDL] Fatal signal when initiaize with USB joystick on 2.6.2 kern
On Fri, 2004-03-05 at 15:09, Sam Lantinga wrote:
> > Fred, how does the attached patch work for you? Do all your axes work?
>
> I think you meant the two lines to be reversed.
> I checked a more robust version of this into CVS. Fred, can you see if
> it works?
You've misread the code. :-/
For coef[0] and coef[1], it is (values[2]+values[1]) / 2 and then add
or subtract values[4] to the answer.
--- a/src/joystick/linux/SDL_sysjoystick.c Fri Mar 05 15:09:18 2004 +0000
+++ b/src/joystick/linux/SDL_sysjoystick.c Sat Mar 06 02:58:06 2004 +0000
@@ -436,17 +436,15 @@
joystick->hwdata->abs_correct[i].used = 0;
} else {
joystick->hwdata->abs_correct[i].used = 1;
- t = (2 - values[4]);
- if ( t != 0 ) {
- joystick->hwdata->abs_correct[i].coef[0] = (values[2] + values[1]) / t;
- }
- t = (2 + values[4]);
- if ( t != 0 ) {
- joystick->hwdata->abs_correct[i].coef[1] = (values[2] + values[1]) / t;
- }
+ joystick->hwdata->abs_correct[i].coef[0] =
+ (values[2] + values[1]) / 2 - values[4];
+ joystick->hwdata->abs_correct[i].coef[1] =
+ (values[2] + values[1]) / 2 + values[4];
t = ((values[2] - values[1]) / 2 - 2 * values[4]);
if ( t != 0 ) {
joystick->hwdata->abs_correct[i].coef[2] = (1 << 29) / t;
+ } else {
+ joystick->hwdata->abs_correct[i].coef[2] = 0;
}
}
++joystick->naxes;