annotate docs/man3/SDL_SetGamma.3 @ 852:2651b6b43840

Quartz fix: ut2004 makes a 2D window for the splash screen, which sets the screen surface's pixels field. Then we tear down that video mode and create a GL context, and the Quartz target isn't resetting the pixels field to NULL. When you just create a GL window, the structure is memset'd to zero the first time through, so unless you hit ut2004's codepath, you won't see the bug. :) Without this patch, quitting a windowed ut2003/ut2004 game makes the OS dump a warning about a bogus free() to stderr, but it doesn't actually crash. All we need to do is explicitly initialize the current->pixels field.
author Ryan C. Gordon <icculus@icculus.org>
date Tue, 24 Feb 2004 06:53:22 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
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e5bc29de3f0a Updated from the SDL Documentation Project
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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