Layer.kt

package org.hexworks.zircon.api.graphics

import org.hexworks.zircon.api.behavior.Boundable
import org.hexworks.zircon.api.behavior.CanBeHidden
import org.hexworks.zircon.api.behavior.TilesetOverride
import org.hexworks.zircon.api.data.Position
import org.hexworks.zircon.api.data.Tile
import org.hexworks.zircon.api.grid.TileGrid
import org.hexworks.zircon.internal.behavior.Identifiable
import org.hexworks.zircon.internal.graphics.InternalLayer

/**
 * A [Layer] is a [TileGraphics] which can be positioned and moved over a [TileGrid].
 * With [Layer]s one can create a quasi 3D effect (like top-down oblique projections).
 */
interface Layer : Boundable, CanBeHidden, Identifiable, TileGraphics, TilesetOverride {

    override fun createCopy(): Layer

    /**
     * Returns this [Layer] as an [InternalLayer] that represents Zircon's internal API.
     */
    fun asInternal(): InternalLayer

    /**
     * Same as [TileGraphics.getTileAtOrNull] but will consider the given [position]
     * as an absolute position (the position is relative to the top left corner
     * of the screen, not the top left corner of the [Layer]).
     */
    fun getAbsoluteTileAtOrNull(position: Position): Tile?

    /**
     * Same as [TileGraphics.getTileAtOrElse] but will consider the given [position]
     * as an absolute position (the position is relative to the top left corner
     * of the screen, not the top left corner of the [Layer]).
     */
    fun getAbsoluteTileAtOrElse(position: Position, orElse: (position: Position) -> Tile): Tile

    /**
     * Same as [TileGraphics.draw] but will consider the given [position]
     * as an absolute position (the position is relative to the top left corner
     * of the screen, not the top left corner of the [Layer]).
     */
    fun drawAbsoluteTileAt(position: Position, tile: Tile)

}