Move rectangle functions to new cairo-rectangle.c

1 files changed, 85 insertions, 0 deletions

diff --git a/src/cairo-rectangle.c b/src/cairo-rectangle.c
new file mode 100644
index 000000000..2f30e92d7
--- /dev/null
+++ b/src/cairo-rectangle.c
@@ -0,0 +1,85 @@
+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2002 University of Southern California
+ * Copyright © 2005 Red Hat, Inc.
+ * Copyright © 2006 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is University of Southern
+ * California.
+ *
+ * Contributor(s):
+ *	Carl D. Worth <cworth@cworth.org>
+ */
+
+#include "cairoint.h"
+
+/* XXX We currently have a confusing mix of boxes and rectangles as
+ * exemplified by this function.  A cairo_box_t is a rectangular area
+ * represented by the coordinates of the upper left and lower right
+ * corners, expressed in fixed point numbers.  A cairo_rectangle_fixed_t is
+ * also a rectangular area, but represented by the upper left corner
+ * and the width and the height, as integer numbers.
+ *
+ * This function converts a cairo_box_t to a cairo_rectangle_fixed_t by
+ * increasing the area to the nearest integer coordinates.  We should
+ * standardize on cairo_rectangle_fixed_t and cairo_rectangle_fixed_t, and
+ * this function could be renamed to the more reasonable
+ * _cairo_rectangle_fixed_round.
+ */
+
+void
+_cairo_box_round_to_rectangle (cairo_box_t *box, cairo_rectangle_fixed_t *rectangle)
+{
+    rectangle->x = _cairo_fixed_integer_floor (box->p1.x);
+    rectangle->y = _cairo_fixed_integer_floor (box->p1.y);
+    rectangle->width = _cairo_fixed_integer_ceil (box->p2.x) - rectangle->x;
+    rectangle->height = _cairo_fixed_integer_ceil (box->p2.y) - rectangle->y;
+}
+
+void
+_cairo_rectangle_intersect (cairo_rectangle_fixed_t *dest, cairo_rectangle_fixed_t *src)
+{
+    int x1, y1, x2, y2;
+
+    x1 = MAX (dest->x, src->x);
+    y1 = MAX (dest->y, src->y);
+    x2 = MIN (dest->x + dest->width, src->x + src->width);
+    y2 = MIN (dest->y + dest->height, src->y + src->height);
+
+    if (x1 >= x2 || y1 >= y2) {
+	dest->x = 0;
+	dest->y = 0;
+	dest->width = 0;
+	dest->height = 0;
+    } else {
+	dest->x = x1;
+	dest->y = y1;
+	dest->width = x2 - x1;
+	dest->height = y2 - y1;
+    }	
+}