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-rw-r--r--distrib/sdl-1.2.12/src/video/SDL_gamma.c233
1 files changed, 0 insertions, 233 deletions
diff --git a/distrib/sdl-1.2.12/src/video/SDL_gamma.c b/distrib/sdl-1.2.12/src/video/SDL_gamma.c
deleted file mode 100644
index a70a1f5..0000000
--- a/distrib/sdl-1.2.12/src/video/SDL_gamma.c
+++ /dev/null
@@ -1,233 +0,0 @@
-/*
- SDL - Simple DirectMedia Layer
- Copyright (C) 1997-2006 Sam Lantinga
-
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this library; if not, write to the Free Software
- Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
-
- Sam Lantinga
- slouken@libsdl.org
-*/
-#include "SDL_config.h"
-
-/* Gamma correction support */
-
-#ifdef HAVE_MATH_H
-#include <math.h> /* Used for calculating gamma ramps */
-#else
-/* Math routines from uClibc: http://www.uclibc.org */
-#include "math_private.h"
-#include "e_sqrt.h"
-#include "e_pow.h"
-#include "e_log.h"
-#define pow(x, y) __ieee754_pow(x, y)
-#define log(x) __ieee754_log(x)
-#endif
-
-#include "SDL_sysvideo.h"
-
-
-static void CalculateGammaRamp(float gamma, Uint16 *ramp)
-{
- int i;
-
- /* 0.0 gamma is all black */
- if ( gamma <= 0.0f ) {
- for ( i=0; i<256; ++i ) {
- ramp[i] = 0;
- }
- return;
- } else
- /* 1.0 gamma is identity */
- if ( gamma == 1.0f ) {
- for ( i=0; i<256; ++i ) {
- ramp[i] = (i << 8) | i;
- }
- return;
- } else
- /* Calculate a real gamma ramp */
- { int value;
- gamma = 1.0f / gamma;
- for ( i=0; i<256; ++i ) {
- value = (int)(pow((double)i/256.0, gamma)*65535.0+0.5);
- if ( value > 65535 ) {
- value = 65535;
- }
- ramp[i] = (Uint16)value;
- }
- }
-}
-static void CalculateGammaFromRamp(float *gamma, Uint16 *ramp)
-{
- /* The following is adapted from a post by Garrett Bass on OpenGL
- Gamedev list, March 4, 2000.
- */
- float sum = 0.0f;
- int i, count = 0;
-
- *gamma = 1.0;
- for ( i = 1; i < 256; ++i ) {
- if ( (ramp[i] != 0) && (ramp[i] != 65535) ) {
- double B = (double)i / 256.0;
- double A = ramp[i] / 65535.0;
- sum += (float) ( log(A) / log(B) );
- count++;
- }
- }
- if ( count && sum > 0.0f ) {
- *gamma = 1.0f / (sum / count);
- }
-}
-
-int SDL_SetGamma(float red, float green, float blue)
-{
- int succeeded;
- SDL_VideoDevice *video = current_video;
- SDL_VideoDevice *this = current_video;
-
- succeeded = -1;
- /* Prefer using SetGammaRamp(), as it's more flexible */
- {
- Uint16 ramp[3][256];
-
- CalculateGammaRamp(red, ramp[0]);
- CalculateGammaRamp(green, ramp[1]);
- CalculateGammaRamp(blue, ramp[2]);
- succeeded = SDL_SetGammaRamp(ramp[0], ramp[1], ramp[2]);
- }
- if ( (succeeded < 0) && video->SetGamma ) {
- SDL_ClearError();
- succeeded = video->SetGamma(this, red, green, blue);
- }
- return succeeded;
-}
-
-/* Calculating the gamma by integrating the gamma ramps isn't exact,
- so this function isn't officially supported.
-*/
-int SDL_GetGamma(float *red, float *green, float *blue)
-{
- int succeeded;
- SDL_VideoDevice *video = current_video;
- SDL_VideoDevice *this = current_video;
-
- succeeded = -1;
- /* Prefer using GetGammaRamp(), as it's more flexible */
- {
- Uint16 ramp[3][256];
-
- succeeded = SDL_GetGammaRamp(ramp[0], ramp[1], ramp[2]);
- if ( succeeded >= 0 ) {
- CalculateGammaFromRamp(red, ramp[0]);
- CalculateGammaFromRamp(green, ramp[1]);
- CalculateGammaFromRamp(blue, ramp[2]);
- }
- }
- if ( (succeeded < 0) && video->GetGamma ) {
- SDL_ClearError();
- succeeded = video->GetGamma(this, red, green, blue);
- }
- return succeeded;
-}
-
-int SDL_SetGammaRamp(const Uint16 *red, const Uint16 *green, const Uint16 *blue)
-{
- int succeeded;
- SDL_VideoDevice *video = current_video;
- SDL_VideoDevice *this = current_video;
- SDL_Surface *screen = SDL_PublicSurface;
-
- /* Verify the screen parameter */
- if ( !screen ) {
- SDL_SetError("No video mode has been set");
- return -1;
- }
-
- /* Lazily allocate the gamma tables */
- if ( ! video->gamma ) {
- SDL_GetGammaRamp(0, 0, 0);
- }
-
- /* Fill the gamma table with the new values */
- if ( red ) {
- SDL_memcpy(&video->gamma[0*256], red, 256*sizeof(*video->gamma));
- }
- if ( green ) {
- SDL_memcpy(&video->gamma[1*256], green, 256*sizeof(*video->gamma));
- }
- if ( blue ) {
- SDL_memcpy(&video->gamma[2*256], blue, 256*sizeof(*video->gamma));
- }
-
- /* Gamma correction always possible on split palettes */
- if ( (screen->flags & SDL_HWPALETTE) == SDL_HWPALETTE ) {
- SDL_Palette *pal = screen->format->palette;
-
- /* If physical palette has been set independently, use it */
- if(video->physpal)
- pal = video->physpal;
-
- SDL_SetPalette(screen, SDL_PHYSPAL,
- pal->colors, 0, pal->ncolors);
- return 0;
- }
-
- /* Try to set the gamma ramp in the driver */
- succeeded = -1;
- if ( video->SetGammaRamp ) {
- succeeded = video->SetGammaRamp(this, video->gamma);
- } else {
- SDL_SetError("Gamma ramp manipulation not supported");
- }
- return succeeded;
-}
-
-int SDL_GetGammaRamp(Uint16 *red, Uint16 *green, Uint16 *blue)
-{
- SDL_VideoDevice *video = current_video;
- SDL_VideoDevice *this = current_video;
-
- /* Lazily allocate the gamma table */
- if ( ! video->gamma ) {
- video->gamma = SDL_malloc(3*256*sizeof(*video->gamma));
- if ( ! video->gamma ) {
- SDL_OutOfMemory();
- return -1;
- }
- if ( video->GetGammaRamp ) {
- /* Get the real hardware gamma */
- video->GetGammaRamp(this, video->gamma);
- } else {
- /* Assume an identity gamma */
- int i;
- for ( i=0; i<256; ++i ) {
- video->gamma[0*256+i] = (i << 8) | i;
- video->gamma[1*256+i] = (i << 8) | i;
- video->gamma[2*256+i] = (i << 8) | i;
- }
- }
- }
-
- /* Just copy from our internal table */
- if ( red ) {
- SDL_memcpy(red, &video->gamma[0*256], 256*sizeof(*red));
- }
- if ( green ) {
- SDL_memcpy(green, &video->gamma[1*256], 256*sizeof(*green));
- }
- if ( blue ) {
- SDL_memcpy(blue, &video->gamma[2*256], 256*sizeof(*blue));
- }
- return 0;
-}
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