void LoadGlImage(GlTexture& tex, const std::string& filename, bool sampling_linear)
{
const GLenum chtypes[] = {
GL_ALPHA, GL_LUMINANCE_ALPHA,
GL_RGB, GL_RGBA
};
TypedImage img = LoadImage(filename);
const GLint format = chtypes[img.fmt.channels];
const GLint imgtype = GL_UNSIGNED_BYTE;
tex.Reinitialise(img.w, img.h, format, sampling_linear, 0, format, imgtype, img.ptr );
img.Dealloc();
}
