setPixelFrom method
Sets a pixels at (dstX,dstY) with value from src at (srcX,srcY).
Implementation
void setPixelFrom(PCanvasPixels src, int srcX, int srcY, int dstX, int dstY) {
  _checkSameFormat(src);
  _setPixelFromImpl(src, srcX, srcY, dstX, dstY);
}