gfxFree function
        
void
gfxFree()
        
     
    
    
Implementation
void gfxFree() {
  for (var i = 0; i < 256; i++) {
    if (gfxPrimitivesFont[i] != nullptr) {
      sdlDestroyTexture(gfxPrimitivesFont[i]);
      gfxPrimitivesFont[i] = nullptr;
    }
  }
}