(svn r5946) -Add: merged the TGP branch to mainline. TGP adds:

  - New optional landscape generator (TerraGenesis Perlin)
  - Load heightmaps (either BMP or PNG)
  - Progress dialog while generating worlds (no longer a 'hanging' screen)
  - New dialogs for NewGame, Create Scenario and Play Heightmap
    - Easier to configure your landscape
    - More things to configure (tree-placer, ..)
  - Speedup of world generation
  - New console command 'restart': restart the map EXACTLY as it was when you
      first started it (needs a game made after or with this commit)
  - New console command 'getseed': get the seed of your map and share it with
      others (of course only works with generated maps)
  - Many new, world generation related, things
  - Many internal cleanups and rewrites
  Many tnx to those people who helped making this:
     Belugas, DaleStan, glx, KUDr, RichK67, Rubidium, and TrueLight (alfabetic)
  Many tnx to those who helped testing:
     Arnau, Bjarni, and tokai (alfabetic)
  And to all other people who helped testing and sending comments / bugs
  Stats: 673 lines changed, 3534 new lines, 79 new strings

1 files changed, 33 insertions, 0 deletions

diff --git a/heightmap.h b/heightmap.h
new file mode 100644
index 000000000..d7592bf27
--- /dev/null
+++ b/heightmap.h
@@ -0,0 +1,33 @@
+/* $Id$ */
+
+#ifndef HEIGHTMAP_H
+#define HEIGHTMAP_H
+
+/*
+ * Order of these enums has to be the same as in lang/english.txt
+ * Otherwise you will get inconsistent behaviour.
+ */
+enum {
+	HM_COUNTER_CLOCKWISE, //! Rotate the map counter clockwise 45 degrees
+	HM_CLOCKWISE,         //! Rotate the map clockwise 45 degrees
+};
+
+/**
+ * Get the dimensions of a heightmap.
+ * @return Returns false if loading of the image failed.
+ */
+bool GetHeightmapDimensions(char *filename, uint *x, uint *y);
+
+/**
+ * Load a heightmap from file and change the map in his current dimensions
+ *  to a landscape representing the heightmap.
+ * It converts pixels to height. The brighter, the higher.
+ */
+void LoadHeightmap(char *filename);
+
+/**
+ * Make an empty world where all tiles are of height 'tile_height'.
+ */
+void FlatEmptyWorld(byte tile_height);
+
+#endif /* HEIGHTMAP_H */