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GlyphCanvas.vala
/*
	Copyright (C) 2012 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 Cairo;
using Math;

namespace BirdFont {

public class GlyphCanvas : GLib.Object {

	/** Tab content. */
	public static FontDisplay current_display;
	
	public signal void signal_redraw_area (int x, int y, int w, int h);
	public static WidgetAllocation allocation;
	
	public GlyphCanvas () {
		allocation = new WidgetAllocation ();
	}

	public static WidgetAllocation get_allocation () {
		return allocation;
	}

	public static void set_allocation (WidgetAllocation w) {
		allocation = w.copy ();
	}

	public void key_release (uint e) {
		current_display.key_release (e);
	}
	
	public void key_press (uint e) {
		current_display.key_press (e);
	}
	
	public static void set_display (FontDisplay fd) {
		current_display = fd;
	}
	
	public void set_current_glyph_collection (GlyphCollection gc, bool signal_selected = true) {
		Glyph g = gc.get_current ();
		
		BirdFont.current_glyph_collection = gc;
		g.resized (allocation);
		
		if (!is_null (current_display)) {
			if (signal_selected) {
				current_display.selected_canvas ();
				FontDisplay.dirty_scrollbar = true;
			}
			
			current_display.redraw_area.connect ((x, y, w, h) => {
				signal_redraw_area ((int)x, (int)y, (int)w, (int)h);
			});

			redraw ();
		}
		 
		if (!is_null (MainWindow.native_window)) {
			MainWindow.native_window.update_window_size ();
		}
	}
	
	public static Glyph get_current_glyph ()  {
		return MainWindow.get_current_glyph ();
	}
	
	public FontDisplay get_current_display () {
		return current_display;
	}

	public void redraw_area (int x, int y, int w, int h) {
		if (MenuTab.has_suppress_event ()) {
			warning ("Do not call redraw from background thread.");
		} else {
			signal_redraw_area (x, y, w + (int) MainWindow.scrollbar.width, h);
		}
	}
	
	public static void redraw () {
		GlyphCanvas c = MainWindow.get_glyph_canvas ();
		if (!is_null (c) && !is_null (MainWindow.scrollbar)) {
			int w = (int) (allocation.width + MainWindow.scrollbar.width);
			c.redraw_area (0, 0, w, allocation.height);
		}
	}
}

}

Contact

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