genode/os/src/server/nitpicker/include/draw_label.h

/*
 * \brief  Support functions for drawing outlined labels
 * \author Norman Feske
 * \date   2006-08-22
 */

/*
 * Copyright (C) 2006-2012 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 _DRAW_LABEL_H_
#define _DRAW_LABEL_H_

extern Font default_font;

/*
 * Gap between session label and view title in pixels
 */
enum { LABEL_GAP = 5 };

/**
 * Draw black outline of string
 */
inline void draw_string_outline(Canvas *canvas, Point pos, const char *s)
{
	for (int j = -1; j <= 1; j++)
		for (int i = -1; i <= 1; i++)
			if (i || j)
				canvas->draw_string(pos + Point(i, j), &default_font, BLACK, s);
}


/**
 * Return bounding box of composed label displayed with the default font
 *
 * \param sl  session label string
 * \param vt  view title string
 */
inline Area label_size(const char *sl, const char *vt) {
	return Area(default_font.str_w(sl) + LABEL_GAP + default_font.str_w(vt) + 2,
	            default_font.str_h(sl) + 2); }


/**
 * Draw outlined view label
 *
 * View labels are composed of two parts: the session label and the view title.
 * The unforgeable session label is defined on session creation by system
 * policy. In contrast, the view title can individually be defined by the
 * application.
 */
static void draw_label(Canvas *canvas, Point pos,
                       const char *session_label, Color session_label_color,
                       const char *view_title,    Color view_title_color)
{
	pos = pos + Point(1, 1);

	draw_string_outline(canvas, pos, session_label);
	canvas->draw_string(pos, &default_font, session_label_color, session_label);

	pos = pos + Point(default_font.str_w(session_label) + LABEL_GAP, 0);

	draw_string_outline(canvas, pos, view_title);
	canvas->draw_string(pos, &default_font, view_title_color, view_title);
}

#endif /* _DRAW_LABEL_H_ */