package tomo

import "io"
import "image"

// Texture is a handle that points to a 2D raster image managed by the backend.
type Texture interface {
	io.Closer

	// Clip returns a smaller section of this texture, pointing to the same
	// internal data. Becaue of this, closing a clipped section will close
	// the original texture as well.
	Clip (image.Rectangle) Texture
}

type protectedTexture struct {
	Texture
}

func (protectedTexture) Close () error {
	return nil
}

// Protect makes the Close() method of a texture do nothing. This is useful if
// several of the same texture are given out to different objects, but only one
// has the responsibility of closing it.
func Protect (texture Texture) Texture {
	return protectedTexture { Texture: texture }
}