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OrientationTool.vala
/*
	Copyright (C) 2015 Johan Mattsson

	This library is free software; you can redistribute it and/or modify 
	it under the terms of the GNU Lesser General Public License as 
	published by the Free Software Foundation; either version 3 of the 
	License, or (at your option) any later version.

	This library is distributed in the hope that it will be useful, but 
	WITHOUT ANY WARRANTY; without even the implied warranty of 
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
	Lesser General Public License for more details.
*/

using Math;
using Cairo;

namespace BirdFont {

public class OrientationTool : Tool {

	double time = 0;
	bool count_down = false;
	
	public OrientationTool (string name, string tip) {
		base (name, tip);
		
		set_icon ("orientation_both");

		select_action.connect ((self) => {
			Glyph g = MainWindow.get_current_glyph ();
			
			foreach (Path p in g.active_paths) {
				p.reverse ();
			}

			count_down = true;
			Glyph.show_orientation_arrow = true;
			Glyph.orientation_arrow_opacity = 1;
			time = 10;
			fade_out ();

			update_icon ();
			GlyphCanvas.redraw ();
		});
		
		DrawingTools.move_tool.selection_changed.connect (() => {
			update_icon ();
		});
	}
	
	public void update_icon () {
		Glyph glyph = MainWindow.get_current_glyph ();
		bool has_clockwise_paths = false;
		bool has_counter_clockwise_paths = false;
		
		foreach (Path p in glyph.active_paths) {
			if (p.is_clockwise ()) {
				has_clockwise_paths = true;
			}
			
			if (!p.is_clockwise ()) {
				has_counter_clockwise_paths = true;
			}
		}
		
		if (has_clockwise_paths && has_counter_clockwise_paths) {
			set_icon ("orientation_both");
		} else if (has_clockwise_paths) {
			set_icon ("orientation_clockwise");
		} else if (has_counter_clockwise_paths) {
			set_icon ("orientation_counter_clockwise");
		} else {
			set_icon ("orientation_both");
		}
		
		Toolbox.redraw_tool_box ();
	}
	
	public void fade_out () {
			TimeoutSource timer = new TimeoutSource (100);
			timer.set_callback (() => {
				if (count_down) {
					if (time <= 0) {
						Glyph.show_orientation_arrow = false;
						count_down = false;
					}
					
					if (time < 1) {
						Glyph.orientation_arrow_opacity = time;
						GlyphCanvas.redraw ();
					}
					
					time -= 0.1;
				} else {
					Glyph.show_orientation_arrow = false;
				}
				
				return count_down;
			});
			timer.attach (null);
	}
}

}

Contact

Email: johan.mattsson.m@gmail.com
Mastodon: typo.social/@birdfont
GitHub: johanmattssonm
LinkedIn: johan-mattsson-2ab324112