internal/graphicscommand/command.go
func (c *replacePixelsCommand) Exec(indexOffset int) error {
	c.dst.image.ReplacePixels(c.pixels, c.x, c.y, c.width, c.height)
	return nil
}
func (c *replacePixelsCommand) Exec(indexOffset int) error {
	c.dst.image.ReplacePixels(c.pixels, c.x, c.y, c.width, c.height)
	return nil
}
// Exec executes the replacePixelsCommand.