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annotate docs/man3/SDL_JoystickGetBall.3 @ 3880:74e828c64315 SDL-1.2

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Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
181
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1 .TH "SDL_JoystickGetBall" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference"
0
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2 .SH "NAME"
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3 SDL_JoystickGetBall\- Get relative trackball motion
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4 .SH "SYNOPSIS"
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5 .PP
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6 \fB#include "SDL\&.h"
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7 .sp
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8 \fBint \fBSDL_JoystickGetBall\fP\fR(\fBSDL_Joystick *joystick, int ball, int *dx, int *dy\fR);
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9 .SH "DESCRIPTION"
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10 .PP
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11 Get the \fBball\fR axis change\&.
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12 .PP
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13 Trackballs can only return relative motion since the last call to \fBSDL_JoystickGetBall\fP, these motion deltas a placed into \fBdx\fR and \fBdy\fR\&.
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14 .SH "RETURN VALUE"
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15 .PP
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16 Returns \fB0\fR on success or \fB-1\fR on failure
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17 .SH "EXAMPLES"
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18 .PP
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19 .PP
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20 .nf
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21 \f(CWint delta_x, delta_y;
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22 SDL_Joystick *joy;
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23 \&.
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24 \&.
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25 \&.
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26 SDL_JoystickUpdate();
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27 if(SDL_JoystickGetBall(joy, 0, &delta_x, &delta_y)==-1)
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28 printf("TrackBall Read Error!
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29 ");
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30 printf("Trackball Delta- X:%d, Y:%d
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31 ", delta_x, delta_y);\fR
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32 .fi
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33 .PP
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34 .SH "SEE ALSO"
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35 .PP
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36 \fI\fBSDL_JoystickNumBalls\fP\fR
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37 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00