+PixelFormat get_sized_pixelformat(PixelFormat pf, unsigned size)
+{
+ if(!size || size>4)
+ throw invalid_argument("get_sized_pixelformat");
+
+ pf = get_unsized_pixelformat(pf);
+
+ switch(size)
+ {
+ case 1:
+ switch(pf)
+ {
+ case RED: return R8;
+ case RG: return RG8;
+ case RGB: return RGB8;
+ case RGBA: return RGBA8;
+ case SRGB: return SRGB8;
+ case SRGB_ALPHA: return SRGB8_ALPHA8;
+ case LUMINANCE: return LUMINANCE8;
+ case SLUMINANCE: return SLUMINANCE8;
+ case LUMINANCE_ALPHA: return LUMINANCE8_ALPHA8;
+ case SLUMINANCE_ALPHA: return SLUMINANCE8_ALPHA8;
+ default: throw invalid_argument("get_sized_pixelformat");
+ }
+ case 2:
+ switch(pf)
+ {
+ case RED: return R16F;
+ case RG: return RG16F;
+ case RGB: return RGB16F;
+ case RGBA: return RGBA16F;
+ case DEPTH_COMPONENT: return DEPTH_COMPONENT16;
+ default: throw invalid_argument("get_sized_pixelformat");
+ }
+ case 3:
+ if(pf==DEPTH_COMPONENT)
+ return DEPTH_COMPONENT24;
+ else
+ throw invalid_argument("get_sized_pixelformat");
+ case 4:
+ switch(pf)
+ {
+ case RED: return R32F;
+ case RG: return RG32F;
+ case RGB: return RGB32F;
+ case RGBA: return RGBA32F;
+ case DEPTH_COMPONENT: return ARB_depth_buffer_float ? DEPTH_COMPONENT32F : DEPTH_COMPONENT32;
+ default: throw invalid_argument("get_sized_pixelformat");
+ }
+ default:
+ throw invalid_argument("get_sized_pixelformat");
+ }
+}
+
+PixelFormat get_default_sized_pixelformat(PixelFormat pf)
+{
+ pf = get_unsized_pixelformat(pf);
+ unsigned size = 1;
+ if(pf==DEPTH_COMPONENT)
+ {
+ if(get_gl_api()==OPENGL_ES2 && !ARB_depth_buffer_float)
+ size = 2;
+ else
+ size = 4;
+ }
+ return get_sized_pixelformat(pf, size);
+}
+
+PixelFormat get_srgb_pixelformat(PixelFormat pf)
+{
+ switch(pf)
+ {
+ case RGB: return SRGB;
+ case RGBA: return SRGB_ALPHA;
+ case RGB8: return SRGB8;
+ case RGBA8: return SRGB8_ALPHA8;
+ case LUMINANCE: return SLUMINANCE;
+ case LUMINANCE8: return SLUMINANCE8;
+ case LUMINANCE_ALPHA: return SLUMINANCE_ALPHA;
+ case LUMINANCE_ALPHA8: return SLUMINANCE8_ALPHA8;
+ default: return pf;
+ }
+}
+
+unsigned get_component_count(PixelFormat pf)
+{
+ switch(get_base_pixelformat(pf))
+ {
+ case STENCIL_INDEX:
+ case DEPTH_COMPONENT:
+ case RED:
+ case LUMINANCE:
+ case SLUMINANCE:
+ return 1;
+ case RG:
+ case LUMINANCE_ALPHA:
+ case SLUMINANCE_ALPHA:
+ return 2;
+ case RGB:
+ case BGR:
+ return 3;
+ case RGBA:
+ case BGRA:
+ return 4;
+ default:
+ throw invalid_argument("get_component_count");
+ }
+}
+
+unsigned get_component_size(PixelFormat pf)
+{
+ switch(pf)
+ {
+ case R8:
+ case RG8:
+ case RGB8:
+ case RGBA8:
+ case SRGB8:
+ case SRGB8_ALPHA8:
+ case LUMINANCE8:
+ case LUMINANCE8_ALPHA8:
+ case SLUMINANCE8:
+ case SLUMINANCE8_ALPHA8:
+ return 1;
+ case R16F:
+ case RG16F:
+ case RGB16F:
+ case RGBA16F:
+ case DEPTH_COMPONENT16:
+ return 2;
+ case DEPTH_COMPONENT24:
+ return 3;
+ case R32F:
+ case RG32F:
+ case RGB32F:
+ case RGBA32F:
+ case DEPTH_COMPONENT32:
+ case DEPTH_COMPONENT32F:
+ return 4;
+ default:
+ return 0;
+ }
+}
+
+unsigned get_pixel_size(PixelFormat pf)
+{
+ return get_component_count(pf)*max(get_component_size(pf), 1U);
+}
+