add initial loadTexture() source

Makefile

@@ -0,0 +1,10 @@
+export SCONSFLAGS := -Q
+
+all:
+	@scons
+
+install:
+	@scons $@
+
+clean:
+	@scons -c

SConstruct

@@ -0,0 +1,6 @@
+# vim:filetype=python
+
+env = Environment(LIBS = ['GL'], CFLAGS = ['-Wall', '-O2'])
+env.ParseConfig('sdl-config --cflags --libs')
+
+env.Object('loadTexture.o', 'loadTexture.c')

loadTexture.c

@@ -0,0 +1,59 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <SDL.h>
+#include <SDL_image.h>
+#include "loadTexture.h"
+
+GLuint loadTexture(const char *filename)
+{
+    GLuint texture;
+    SDL_Surface * temp = IMG_Load(filename);
+    if (!temp)
+    {
+        fprintf(stderr, "Failed to load image '%s'!\n", filename);
+        return 0;
+    }
+
+    SDL_PixelFormat fmt;
+    fmt.palette = NULL;
+    fmt.BitsPerPixel = 32;
+    fmt.BytesPerPixel = 4;
+    fmt.Rmask = 0x000000FF;
+    fmt.Gmask = 0x0000FF00;
+    fmt.Bmask = 0x00FF0000;
+    fmt.Amask = 0xFF000000;
+    fmt.Rshift = 0;
+    fmt.Gshift = 8;
+    fmt.Bshift = 16;
+    fmt.Ashift = 24;
+
+    SDL_Surface * texsurf = SDL_ConvertSurface(temp, &fmt, SDL_SWSURFACE);
+    SDL_FreeSurface(temp);
+    if (!texsurf)
+    {
+        fprintf(stderr, "'%s' was not converted properly!\n", filename);
+        return 0;
+    }
+    unsigned int * pixels =
+        malloc(sizeof(unsigned int) * texsurf->w * texsurf->h);
+    int y;
+    unsigned int dstOffset = texsurf->w * (texsurf->h - 1);
+    unsigned int srcOffset = 0;
+    for (y = 0; y < texsurf->h; y++)
+    {
+        memcpy(pixels + dstOffset,
+            ((unsigned int *)texsurf->pixels) + srcOffset,
+            texsurf->w << 2);
+        dstOffset -= texsurf->w;
+        srcOffset += texsurf->w;
+    }
+    glGenTextures(1, &texture);
+    glBindTexture(GL_TEXTURE_2D, texture);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texsurf->w, texsurf->h, 0,
+        GL_RGBA, GL_UNSIGNED_BYTE, pixels);
+
+    SDL_FreeSurface(texsurf);
+    free(pixels);
+    return texture;
+}

loadTexture.h

@@ -0,0 +1,22 @@
+
+#ifndef LOADTEXTURE_H
+#define LOADTEXTURE_H
+
+#ifdef GL_INCLUDE_FILE
+#include GL_INCLUDE_FILE
+#else
+#include <GL/gl.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+GLuint loadTexture(const char *filename);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+