genode/repos/gems/src/app/decorator/canvas.h

118 lines
2.4 KiB
C++

/*
* \brief Graphics back end for example window decorator
* \author Norman Feske
* \date 2014-01-10
*/
/*
* Copyright (C) 2014 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _CANVAS_H_
#define _CANVAS_H_
/* Painters of the nitpicker and scout graphics backends */
#include <nitpicker_gfx/text_painter.h>
#include <nitpicker_gfx/box_painter.h>
#include <scout_gfx/icon_painter.h>
/* decorator includes */
#include <decorator/types.h>
namespace Decorator {
typedef Text_painter::Font Font;
Font &default_font();
enum Texture_id {
TEXTURE_ID_CLOSER,
TEXTURE_ID_MINIMIZE,
TEXTURE_ID_MAXIMIZE,
TEXTURE_ID_WINDOWED
};
Genode::Texture_base const &texture_by_id(Texture_id);
class Canvas_base;
template <typename PT> class Canvas;
class Clip_guard;
}
/**
* Abstract interface of graphics back end
*/
struct Decorator::Canvas_base
{
virtual Rect clip() const = 0;
virtual void clip(Rect) = 0;
virtual void draw_box(Rect, Color) = 0;
virtual void draw_text(Point, Font const &, Color, char const *) = 0;
virtual void draw_texture(Point, Texture_id) = 0;
};
template <typename PT>
class Decorator::Canvas : public Decorator::Canvas_base
{
private:
Genode::Surface<PT> _surface;
public:
Canvas(PT *base, Area size) : _surface(base, size) { }
Rect clip() const override { return _surface.clip(); }
void clip(Rect rect) override { _surface.clip(rect); }
void draw_box(Rect rect, Color color) override
{
Box_painter::paint(_surface, rect, color);
}
void draw_text(Point pos, Font const &font,
Color color, char const *string) override
{
Text_painter::paint(_surface, pos, font, color, string);
}
void draw_texture(Point pos, Texture_id id)
{
Genode::Texture<PT> const &texture =
static_cast<Genode::Texture<PT> const &>(texture_by_id(id));
unsigned const alpha = 255;
Icon_painter::paint(_surface, Rect(pos, texture.size()), texture, alpha);
}
};
class Decorator::Clip_guard : Rect
{
private:
Canvas_base &_canvas;
Rect const _orig_rect;
public:
Clip_guard(Canvas_base &canvas, Rect clip_rect)
:
_canvas(canvas), _orig_rect(canvas.clip())
{
_canvas.clip(Rect::intersect(_orig_rect, clip_rect));
}
~Clip_guard() { _canvas.clip(_orig_rect); }
};
#endif /* _CANVAS_H_ */