boxes: Efficient storage for an array of cairo_box_t.

Currently we use cairo_traps_t to also pass around arrays of boxes. This
is woefully inefficient in terms of storage, but also means that we
repeatedly have to verify that the traps are a set of boxes. By
explicitly passing around a cairo_boxes_t we avoid the semantic loss.

This will be heavily used in pending commits.

1 files changed, 80 insertions, 0 deletions

diff --git a/src/cairo-boxes-private.h b/src/cairo-boxes-private.h
new file mode 100644
index 000000000..881ac3ddc
--- /dev/null
+++ b/src/cairo-boxes-private.h
@@ -0,0 +1,80 @@
+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2009 Intel Corporation
+ *
+ * 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.
+ *
+ * Contributor(s):
+ *	Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#ifndef CAIRO_BOXES_H
+#define CAIRO_BOXES_H
+
+#include "cairo-types-private.h"
+#include "cairo-compiler-private.h"
+
+struct _cairo_boxes_t {
+    cairo_status_t status;
+    cairo_box_t limit;
+    const cairo_box_t *limits;
+    int num_limits;
+    int num_boxes;
+    unsigned int is_pixel_aligned : 1;
+
+    struct _cairo_boxes_chunk {
+	struct _cairo_boxes_chunk *next;
+	cairo_box_t *base;
+	int count;
+	int size;
+    } chunks, *tail;
+    cairo_box_t boxes_embedded[32];
+};
+
+cairo_private void
+_cairo_boxes_init (cairo_boxes_t *boxes);
+
+cairo_private void
+_cairo_boxes_init_for_array (cairo_boxes_t *boxes,
+			     cairo_box_t *array,
+			     int num_boxes);
+
+cairo_private void
+_cairo_boxes_limit (cairo_boxes_t	*boxes,
+		    const cairo_box_t	*limits,
+		    int			 num_limits);
+
+cairo_private cairo_status_t
+_cairo_boxes_add (cairo_boxes_t *boxes,
+		  const cairo_box_t *box);
+
+cairo_private void
+_cairo_boxes_clear (cairo_boxes_t *boxes);
+
+cairo_private void
+_cairo_boxes_fini (cairo_boxes_t *boxes);
+
+#endif /* CAIRO_BOXES_H */