genode/repos/demo/include/scout/window.h
2019-02-19 11:12:11 +01:00

319 lines
7.0 KiB
C++

/*
* \brief Window interface
* \author Norman Feske
* \date 2006-08-30
*/
/*
* Copyright (C) 2006-2017 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__WINDOW_H_
#define _INCLUDE__SCOUT__WINDOW_H_
#include <scout/misc_math.h>
#include <scout/parent_element.h>
#include <scout/platform.h>
#include <scout/graphics_backend.h>
namespace Scout {
class Window;
class Drag_event_handler;
class Sizer_event_handler;
class Mover_event_handler;
}
class Scout::Window : public Parent_element
{
private:
Graphics_backend &_gfx_backend;
Rect _dirty { };
Area _max_size;
int _request_cnt; /* nb of requests since last process */
bool const _scout_quirk; /* enable redraw quirk for scout */
/*
* We limit the rate of (expensive) view-position updates to the rate
* of 'process_redraw' calls instead of eagerly responding to
* individual input events (which trigger calls of 'vpos').
*/
Point _view_position, _next_view_position = _view_position;
void _update_view_position()
{
if (_view_position == _next_view_position) return;
_view_position = _next_view_position;
_gfx_backend.position(_view_position);
}
public:
Window(Graphics_backend &gfx_backend, Point position, Area size,
Area max_size, bool scout_quirk)
:
_gfx_backend(gfx_backend), _max_size(max_size), _request_cnt(0),
_scout_quirk(scout_quirk), _view_position(position)
{
/* init element attributes */
_size = size;
}
virtual ~Window() { }
/**
* Return current window position
*/
int view_x() const { return _next_view_position.x(); }
int view_y() const { return _next_view_position.y(); }
int view_w() const { return _size.w(); }
int view_h() const { return _size.h(); }
Area max_size() const { return _max_size; }
/**
* Bring window to front
*/
virtual void top() { _gfx_backend.bring_to_front(); }
/**
* Move window to new position
*/
virtual void vpos(int x, int y) { _next_view_position = Point(x, y); }
/**
* Define vertical scroll offset
*/
virtual void ypos(int) { }
virtual int ypos() { return 0; }
/**
* Format window
*/
virtual void format(Area size)
{
_gfx_backend.view_area(size);
}
/**
* Element interface
*
* This function just collects the specified regions to be redrawn but
* does not perform any immediate drawing operation. The actual drawing
* must be initiated by calling the process_redraw function.
*/
void redraw_area(int x, int y, int w, int h) override
{
/*
* Scout redraw quirk
*
* Quick fix to avoid artifacts at the icon bar. The icon bar must
* always be drawn completely because of the interaction of the
* different layers.
*/
if (_scout_quirk && y < 64 + 32) {
h = max(h + y, 64 + 32);
w = _size.w();
x = 0;
y = 0;
}
Rect rect(Point(x, y), Area(w, h));
/* first request since last process operation */
if (_request_cnt == 0) {
_dirty = rect;
/* merge subsequencing requests */
} else {
_dirty = Rect::compound(_dirty, rect);
}
_request_cnt++;
}
/**
* Process redrawing operations
*/
void process_redraw()
{
_update_view_position();
if (_request_cnt == 0) return;
/* get actual drawing area (clipped against canvas dimensions) */
int x1 = max(0, _dirty.x1());
int y1 = max(0, _dirty.y1());
int x2 = min((int)_size.w() - 1, _dirty.x2());
int y2 = min((int)_size.h() - 1, _dirty.y2());
if (x1 > x2 || y1 > y2) return;
Canvas_base &canvas = _gfx_backend.back();
canvas.clip(Rect(Point(x1, y1), Area(x2 - x1 + 1, y2 - y1 + 1)));
/* draw into back buffer */
try_draw(canvas, Point(0, 0));
/*
* If we draw the whole area, we can flip the front
* and back buffers instead of copying pixels from the
* back to the front buffer.
*/
/* detemine if the whole area must be drawn */
if (x1 == 0 && x2 == (int)_size.w() - 1
&& y1 == 0 && y2 == (int)_size.h() - 1) {
/* flip back end front buffers */
_gfx_backend.swap_back_and_front();
} else {
_gfx_backend.copy_back_to_front(Rect(Point(x1, y1),
Area(x2 - x1 + 1, y2 - y1 + 1)));
}
/* reset request state */
_request_cnt = 0;
}
};
/********************
** Event handlers **
********************/
class Scout::Drag_event_handler : public Event_handler
{
protected:
int _key_cnt = 0; /* number of curr. pressed keys */
Point _current_mouse_position { };
Point _old_mouse_position { };
virtual void start_drag() = 0;
virtual void do_drag() = 0;
public:
/**
* Constructor
*/
Drag_event_handler() { }
/**
* Event handler interface
*/
void handle_event(Event const &ev) override
{
if (ev.type == Event::PRESS) _key_cnt++;
if (ev.type == Event::RELEASE) _key_cnt--;
if (_key_cnt == 0) return;
/* first click starts dragging */
if ((ev.type == Event::PRESS) && (_key_cnt == 1)) {
_current_mouse_position = _old_mouse_position = ev.mouse_position;
start_drag();
}
/* check if mouse was moved */
if ((ev.mouse_position.x() == _current_mouse_position.x())
&& (ev.mouse_position.y() == _current_mouse_position.y()))
return;
/* remember current mouse position */
_current_mouse_position = ev.mouse_position;
do_drag();
}
};
class Scout::Sizer_event_handler : public Drag_event_handler
{
private:
/*
* Noncopyable
*/
Sizer_event_handler(Sizer_event_handler const &);
Sizer_event_handler &operator = (Sizer_event_handler const &);
protected:
Window *_window;
int _obw = 0, _obh = 0; /* original window size */
/**
* Event handler interface
*/
void start_drag() override
{
_obw = _window->view_w();
_obh = _window->view_h();
}
void do_drag() override
{
/* calculate new window size */
int nbw = _obw + _current_mouse_position.x() - _old_mouse_position.x();
int nbh = _obh + _current_mouse_position.y() - _old_mouse_position.y();
_window->format(Area(nbw, nbh));
}
public:
/**
* Constructor
*/
Sizer_event_handler(Window *window) : _window(window) { }
};
class Scout::Mover_event_handler : public Drag_event_handler
{
private:
/*
* Noncopyable
*/
Mover_event_handler(Mover_event_handler const &);
Mover_event_handler &operator = (Mover_event_handler const &);
protected:
Window *_window;
int _obx = 0, _oby = 0; /* original launchpad position */
void start_drag() override
{
_obx = _window->view_x();
_oby = _window->view_y();
_window->top();
}
void do_drag() override
{
int nbx = _obx + _current_mouse_position.x() - _old_mouse_position.x();
int nby = _oby + _current_mouse_position.y() - _old_mouse_position.y();
_window->vpos(nbx, nby);
}
public:
/**
* Constructor
*/
Mover_event_handler(Window *window) : _window(window) { }
};
#endif /* _INCLUDE__SCOUT__WINDOW_H_ */