genode/repos/demo/include/scout/graphics_backend_impl.h
Norman Feske e738162bde framebuffer_session: alpha as Mode attribute
Propagate the want of an alpha channel as attribute of Framebuffer::Mode
instead of passing this property as a separate bool argument.

This clears the way for adding useful accessors for pixel/alpha/input
surfaces to the Mode type as a subsequent step.

Issue #5351
2024-10-08 09:09:23 +02:00

140 lines
3.2 KiB
C++

/*
* \brief Graphics backend based on the GUI session interface
* \date 2013-12-30
* \author Norman Feske
*/
/*
* Copyright (C) 2013-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _INCLUDE__SCOUT__GRAPHICS_BACKEND_IMPL_H_
#define _INCLUDE__SCOUT__GRAPHICS_BACKEND_IMPL_H_
/* Genode includes */
#include <gui_session/connection.h>
#include <os/pixel_rgb888.h>
#include <base/attached_dataspace.h>
/* Scout includes */
#include <scout/graphics_backend.h>
namespace Scout {
using Genode::Pixel_rgb888;
class Graphics_backend_impl;
}
class Scout::Graphics_backend_impl : public Graphics_backend
{
private:
/*
* Noncopyable
*/
Graphics_backend_impl(Graphics_backend_impl const &);
Graphics_backend_impl &operator = (Graphics_backend_impl const &);
Genode::Region_map &_local_rm;
Gui::Connection &_gui;
Genode::Dataspace_capability _init_fb_ds(Area max_size)
{
_gui.buffer({ .area = { max_size.w, max_size.h*2 }, .alpha = false });
return _gui.framebuffer.dataspace();
}
Area _max_size;
Genode::Attached_dataspace _fb_ds { _local_rm, _init_fb_ds(_max_size) };
Point _position;
Area _view_size;
bool _flip_state = { false };
Gui::Top_level_view _view { _gui, { _position, _view_size } };
template <typename PT>
PT *_base(unsigned idx)
{
return (PT *)_fb_ds.local_addr<PT>() + idx*_max_size.count();
}
using PT = Genode::Pixel_rgb888;
Canvas<PT> _canvas_0, _canvas_1;
Canvas_base *_canvas[2] { &_canvas_0, &_canvas_1 };
unsigned _front_idx() const { return _flip_state ? 1 : 0; }
unsigned _back_idx() const { return _flip_state ? 0 : 1; }
public:
/**
* Constructor
*
* \param alloc allocator used for allocating textures
*/
Graphics_backend_impl(Genode::Region_map &local_rm,
Gui::Connection &gui,
Genode::Allocator &alloc,
Area max_size, Point position, Area view_size)
:
_local_rm(local_rm),
_gui(gui),
_max_size(max_size),
_position(position),
_view_size(view_size),
_canvas_0(_base<PT>(0), max_size, alloc),
_canvas_1(_base<PT>(1), max_size, alloc)
{ }
/********************************
** Graphics_backend interface **
********************************/
Canvas_base &front() override { return *_canvas[_front_idx()]; }
Canvas_base &back() override { return *_canvas[ _back_idx()]; }
void copy_back_to_front(Rect rect) override
{
Point const from = rect.p1() + Point { 0, int( _back_idx()*_max_size.h) };
Point const to = rect.p1() + Point { 0, int(_front_idx()*_max_size.h) };
_gui.framebuffer.blit({ from, rect.area }, to);
}
void swap_back_and_front() override
{
_flip_state = !_flip_state;
_gui.framebuffer.panning({ 0, int(_front_idx()*_max_size.h) });
}
void position(Point p) override
{
_position = p;
_view.at(p);
}
void bring_to_front() override
{
_view.front();
}
void view_area(Area area) override
{
_view_size = area;
_view.area(area);
}
};
#endif /* _INCLUDE__SCOUT__GRAPHICS_BACKEND_IMPL_H_ */