int fond_load_internal(struct fond_font *font, unsigned char *fontdata, stbtt_pack_range *range){
  stbtt_pack_context context = {0};
  unsigned char atlasdata[font->width*font->height] = {0};

  if(!atlasdata){
    errcode = OUT_OF_MEMORY;
    goto fond_load_internal_cleanup;
  }
  
  if(!stbtt_PackBegin(&context, atlasdata, font->width, font->height, 0, 1, 0)){
    errcode = FONT_PACK_FAILED;
    goto fond_load_internal_cleanup;
  }

  stbtt_PackSetOversampling(&context, font->oversample_h, font->oversample_v);

  if(!stbtt_PackFontRanges(&context, fontdata, font->index, &range, 1)){
    errcode = FONT_PACK_FAILED;
    goto fond_load_internal_cleanup;
  }

  stbtt_PackEnd(&context);
  free(fontdata);

  glGenTextures(1, &font->texture);
  glBindTexture(GL_TEXTURE_2D, font->texture);
  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, font->width, font->height, 0, GL_RED, GL_UNSIGNED_BYTE, atlasdata);
  glHint(GL_GENERATE_MIPMAP_HINT, GL_NICEST);
  glGenerateMipmap(GL_TEXTURE_2D);
  glBindTexture(GL_TEXTURE_2D, 0);

  if(glGetError() != GL_NO_ERROR){
    errcode = OPENGL_ERROR;
    goto fond_load_internal_cleanup;
  }
  
  return 1;

 fond_load_internal_cleanup:
  if(atlasdata)
    free(atlasdata);
  
  if(font->texture)
    glDeleteTextures(1, &font->texture);
  font->texture = 0;
  return 0;
}