Overlay.h

#pragma once

#include "Core.h"
#include <VTableInterpose.h>
#include "df/renderer.h"
#include "df/enabler.h"
#include "df/graphic.h"

#include "common.h"

class Overlay : public df::renderer
{
private:
	//size of the current df display's font
	uint8_t fontx, fonty;
	//the pixel-offset of the first DF tile in the top-left corner of the screen
	int32_t offsetx, offsety;
	//the width and height in tiles of the current df display's view
	int32_t width, height;

	//used by the renderer to skip drawing from the overlay buffer if it wasn't updated
	bool front_updated;
	//keeps track of if the most recently visited viewscreen is one it makes sense to overlay
	bool good_viewscreen;

	//need to lock front buffer because SDL and Allegro can't talk to negotiate ownership
    ALLEGRO_MUTEX * front_mutex;

	//our front and back buffers
	ALLEGRO_BITMAP * front;
	ALLEGRO_BITMAP * back;

	ALLEGRO_LOCKED_REGION * front_data;

	renderer * parent;

	//reads tile information, used for resizing and positioning of the overlay
	void ReadTileLocations();
	//updates good_viewscreen
	void CheckViewscreen();
	//determines if the given tile location is within the area we're painting over
	bool PaintingOverTileAt(int32_t, int32_t);

	//df::renderer overrides
	void set_to_null();
	void copy_from_inner();
	void copy_to_inner();

public:
	Overlay(renderer* parent);
	~Overlay();

	void Flip();

	bool GoodViewscreen();

	//df::renderer overrides
	void update_tile(int32_t x, int32_t y);
	void update_all();
	void render();
	void set_fullscreen();
	void zoom(df::zoom_commands z);
	void resize(int32_t w, int32_t h);
	void grid_resize(int32_t w, int32_t h);
	bool get_mouse_coords(int32_t* x, int32_t* y);
	bool uses_opengl();
};