Move island-building code from dgn-shoals.cc->dgn-height.cc.

1 files changed, 104 insertions, 0 deletions

diff --git a/crawl-ref/source/dgn-height.h b/crawl-ref/source/dgn-height.h
new file mode 100644
index 0000000000..1ab5954db4
--- /dev/null
+++ b/crawl-ref/source/dgn-height.h
@@ -0,0 +1,104 @@
+#ifndef DGN_HEIGHT_H
+#define DGN_HEIGHT_H
+
+#include "AppHdr.h"
+#include "externs.h"
+#include "env.h"
+#include "fixedarray.h"
+#include <vector>
+
+// The caller is responsible for ensuring that env.heightmap is set.
+static inline short &dgn_height_at(const coord_def &c)
+{
+    return (*env.heightmap)(c);
+}
+
+typedef FixedArray<bool, GXM, GYM> grid_bool;
+typedef FixedArray<short, GXM, GYM> grid_short;
+typedef std::pair<int, int> int_range;
+
+const int DGN_UNDEFINED_HEIGHT = -10000;
+
+int resolve_range(int_range range, int nrolls = 1);
+
+void dgn_initialise_heightmap(int initial_height = 0);
+void dgn_smooth_height_at(coord_def c, int radius = 1,
+                          int max_height = DGN_UNDEFINED_HEIGHT);
+void dgn_smooth_heights(int radius = 1, int npasses = 1);
+
+
+void dgn_island_centred_at(const coord_def &c,
+                           // Number of times to raise heights of
+                           // points near c.
+                           int n_points,
+
+                           // Radius within which all height
+                           // increments are applied.
+                           int radius,
+
+                           // Lower and upper limits to the height
+                           // delta per perturbation.
+                           int_range height_delta_range,
+
+                           int border_margin = 6,
+
+                           // If make_atoll is set, all points chosen for
+                           // height increment will be close to the specified
+                           // radius from c, thus producing a ragged ring.
+                           bool make_atoll = false);
+
+struct dgn_island_plan
+{
+public:
+    // Number of squares of border to leave around the level.
+    int level_border_depth;
+
+    // Number of auxiliary high points for each island.
+    int_range n_aux_centres;
+
+    // Distance from the island centre where the aux high points are placed.
+    int_range aux_centre_offset_range;
+
+    // Percentage of island (aux) centres that are built as atolls.
+    int atoll_roll;
+
+    // The positions of the primary centre of each island.
+    std::vector<coord_def> islands;
+
+    // The square of the minimum distance that must separate any two
+    // island centres. This is not intended to prevent island overlap, only
+    // to prevent too much clumping of islands.
+    int island_separation_dist2;
+
+    // Number of points near each island centre that will be raised by
+    // the island builder.
+    int_range n_island_centre_delta_points;
+
+    // Range of radii for island primary centres.
+    int_range island_centre_radius_range;
+
+    int_range island_centre_point_height_increment;
+
+    // Number of points near secondary island centres that will be
+    // raised by the island builder.
+    int_range n_island_aux_delta_points;
+
+    // Range of radii for island aux centres.
+    int_range island_aux_radius_range;
+
+    int_range island_aux_point_height_increment;
+
+public:
+    static dgn_island_plan shoals_islands(int margin);
+    static dgn_island_plan snake_chambers(int margin);
+
+public:
+    void build(int nislands);
+    coord_def pick_and_remove_random_island();
+
+private:
+    coord_def pick_island_spot();
+    void build_island();
+};
+
+#endif