gistfile1.m

- (GLvoid)setupOpenGL{
    /* Create buffers */ {
        glGenBuffers(2, buffers);
        // Vertex buffer
        glBindBuffer(GL_ARRAY_BUFFER, buffers[0]);
        glBufferData(GL_ARRAY_BUFFER, sizeof(vbdata), vbdata, GL_STATIC_DRAW);
        // Element buffer
        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, buffers[1]);
        glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(ebdata), ebdata, GL_STATIC_DRAW);
    }
    /* Load textures */ {
        glGenTextures(2, textures);
        GLsizei width, height;
        GLvoid* pixels;
        // Texture #1
        pixels = load_image(@"hello1.png", &width, &height);
        glBindTexture(GL_TEXTURE_2D, textures[0]);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
        glTexImage2D(GL_TEXTURE_2D, 0,
                     GL_RGBA8,
                     width, height, 0,
                     GL_RGBA8, GL_UNSIGNED_BYTE,
                     pixels);
        free(pixels);
        // Texture #2
        pixels = load_image(@"hello2.png", &width, &height);
        glBindTexture(GL_TEXTURE_2D, textures[0]);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
        glTexImage2D(GL_TEXTURE_2D, 0,
                     GL_RGBA8,
                     width, height, 0,
                     GL_RGBA8, GL_UNSIGNED_BYTE,
                     pixels);
        free(pixels);
    }
}