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SDLGL_Util transformed too much

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James Turk 2003-10-13 21:40:57 +00:00
parent 15178a25fa
commit 8b8b4f980e
2 changed files with 0 additions and 98 deletions
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14
include/external/SDLGL_Util.h vendored
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@ -1,14 +0,0 @@
/*This code comes from testgl.c which is part of the SDL source distribution.
Available at http://libsdl.org/
*/
#ifndef __sdlgl_h__
#define __sdlgl_h__
#include "ZE_Includes.h"
#if (GFX_BACKEND == ZE_OGL)
int power_of_two(int input);
GLuint SDL_GL_LoadTexture(SDL_Surface *surface, GLfloat *texcoord);
#endif
#endif //__sdlgl_h__

84
src/external/SDLGL_Util.cpp vendored
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@ -1,84 +0,0 @@
/*This code derived from testgl.c which is part of the SDL source distribution.
Available at http://libsdl.org/
*/
#include "external/SDLGL_Util.h"
#if (GFX_BACKEND == ZE_OGL)
//finds next largest power of two, needed for GL textures
int power_of_two(int input)
{
int value = 1;
while(value < input) //texture coord must be >= input
value <<= 1; //value <<= 1 is the same as value *= 2
return value;
}
GLuint SDL_GL_LoadTexture(SDL_Surface *surface, GLfloat *texcoord)
{
GLuint texture;
int w, h;
SDL_Surface *temp;
SDL_Rect area;
Uint32 saved_flags;
Uint8 saved_alpha;
//expand width and height to nearest powers of 2
w = power_of_two(surface->w);
h = power_of_two(surface->h);
texcoord[0] = 0.0f; //min X
texcoord[1] = 0.0f; //min Y
texcoord[2] = (GLfloat)surface->w / w; //max X
texcoord[3] = (GLfloat)surface->h / h; //max Y
temp = SDL_CreateRGBSurface(
SDL_SWSURFACE,
w, h,
32,
#if SDL_BYTEORDER == SDL_LIL_ENDIAN //endian specific color masks
0x000000FF,
0x0000FF00,
0x00FF0000,
0xFF000000
#else
0xFF000000,
0x00FF0000,
0x0000FF00,
0x000000FF
#endif
);
if(!temp) //failure in CreateRGBSurface
return 0;
//save alpha
saved_flags = surface->flags&(SDL_SRCALPHA|SDL_RLEACCELOK);
saved_alpha = surface->format->alpha;
if((saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA)
SDL_SetAlpha(surface, 0, 0);
//copy surface (do not alter passed surface to allow this function to be used in special situations)
area.x = 0;
area.y = 0;
area.w = static_cast<Sint16>(surface->w);
area.h = static_cast<Sint16>(surface->h);
SDL_BlitSurface(surface, &area, temp, &area);
//restore saved alpha
if((saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA)
SDL_SetAlpha(surface, saved_flags, saved_alpha);
//create the OpenGL texture
glGenTextures(1, &texture);
//setup texture parmaters
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, temp->pixels);
SDL_FreeSurface(temp); //temp surface no longer needed
return texture;
}
#endif //GFX_BACKEND == OGL