Previously graph layout was done using the Kamada-Kawai layout algorithm

implemented in Boost.  I am replacing this with a custom implementation of
a constrained stress-majorization algorithm.

The stress-majorization algorithm is more robust and has better convergence
characteristics than Kamada-Kawai, and also simple constraints can be placed
on node position (for example, to enforce downward-pointing edges, non-overlap constraints, or cluster constraints).

Another big advantage is that we no longer need Boost.

I've tested the basic functionality, but I have yet to properly handle
disconnected graphs or to properly scale the resulting layout.

This commit also includes significant refactoring... the quadratic program solver - libvpsc (Variable Placement with Separation Constraints) has been moved to src/libvpsc and the actual graph layout algorithm is in libcola.

(bzr r1394)

1 files changed, 21 insertions, 0 deletions

diff --git a/src/libvpsc/remove_rectangle_overlap.h b/src/libvpsc/remove_rectangle_overlap.h
new file mode 100644
index 000000000..08b035e31
--- /dev/null
+++ b/src/libvpsc/remove_rectangle_overlap.h
@@ -0,0 +1,21 @@
+#ifndef REMOVE_RECTANGLE_OVERLAP_H_SEEN
+#define REMOVE_RECTANGLE_OVERLAP_H_SEEN
+
+/**
+ * \file Declaration of main internal remove-overlaps function.
+ */
+/*
+ * Authors:
+ *   Tim Dwyer <tgdwyer@gmail.com>
+ *
+ * Copyright (C) 2005 Authors
+ *
+ * Released under GNU LGPL.  Read the file 'COPYING' for more information.
+ */
+
+class Rectangle;
+
+void removeRectangleOverlap(unsigned n, Rectangle *rs[], double xBorder, double yBorder);
+
+
+#endif /* !REMOVE_RECTANGLE_OVERLAP_H_SEEN */