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annotate docs/man3/SDL_SetGamma.3 @ 2042:3908e1f808e1

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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 15:56:36 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
181
e5bc29de3f0a Updated from the SDL Documentation Project
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parents: 55
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1 .TH "SDL_SetGamma" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_SetGamma\- Sets the color gamma function for the display
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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_SetGamma\fP\fR(\fBfloat redgamma, float greengamma, float bluegamma\fR);
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9 .SH "DESCRIPTION"
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10 .PP
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11 Sets the "gamma function" for the display of each color component\&. Gamma controls the brightness/contrast of colors displayed on the screen\&. A gamma value of 1\&.0 is identity (i\&.e\&., no adjustment is made)\&.
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12 .PP
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13 This function adjusts the gamma based on the "gamma function" parameter, you can directly specify lookup tables for gamma adjustment with \fISDL_SetGammaRamp\fR\&.
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14 .PP
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15 Not all display hardware is able to change gamma\&.
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16 .SH "RETURN VALUE"
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17 .PP
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18 Returns -1 on error (or if gamma adjustment is not supported)\&.
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19 .SH "SEE ALSO"
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20 .PP
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21 \fISDL_GetGammaRamp\fR \fISDL_SetGammaRamp\fR
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22 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01