1 files changed, 108 insertions, 0 deletions
diff --git a/crawl-ref/source/dgn-swamp.cc b/crawl-ref/source/dgn-swamp.cc
new file mode 100644
index 0000000000..b20627e2d3
--- /dev/null
+++ b/crawl-ref/source/dgn-swamp.cc
@@ -0,0 +1,108 @@
+#include "AppHdr.h"
+
+#include "coordit.h"
+#include "dungeon.h"
+#include "dgn-height.h"
+#include "random.h"
+
+static void _swamp_slushy_patches(int depth_multiplier)
+{
+    const int margin = 6;
+    const int yinterval = 4;
+    const int xinterval = 4;
+    const int fuzz = 9;
+    const coord_def grdc(GXM / 2, GYM / 2);
+    for (int y = margin; y < GYM - margin - 1; y += yinterval)
+    {
+        for (int x = margin; x < GXM - margin - 1; x += xinterval)
+        {
+            const coord_def p(x, y);
+            const coord_def c(dgn_random_point_from(p, fuzz, margin));
+            const coord_def center_delta(grdc - c);
+            const int depth = 1600 - center_delta.abs();
+            const int depth_offset = depth * 10 / 1600;
+            dgn_island_centred_at(c, random_range(5, 25 - depth_multiplier / 2),
+                                  random_range(2, 6),
+                                  int_range(8 + depth_offset,
+                                            17 + depth_offset),
+                                  margin);
+        }
+    }
+}
+
+static dungeon_feature_type _swamp_feature_for_height(int height)
+{
+    return height >= 14? DNGN_DEEP_WATER :
+        height > 0? DNGN_SHALLOW_WATER :
+        height > -9 ? DNGN_FLOOR :
+        height > -13 ? DNGN_SHALLOW_WATER :
+        height > -17 && coinflip() ? DNGN_SHALLOW_WATER :
+        DNGN_TREES;
+}
+
+static void _swamp_apply_features(int margin)
+{
+    for (rectangle_iterator ri(0); ri; ++ri)
+    {
+        const coord_def c(*ri);
+        if (unforbidden(c, MMT_VAULT))
+        {
+            if (c.x < margin || c.y < margin || c.x >= GXM - margin
+                || c.y >= GYM - margin)
+                grd(c) = DNGN_TREES;
+            else
+               grd(c) = _swamp_feature_for_height(dgn_height_at(c));
+        }
+    }
+}
+
+void dgn_build_swamp_level(int level)
+{
+    const int swamp_depth = level_id::current().depth - 1;
+    dgn_initialise_heightmap(-17);
+    _swamp_slushy_patches(swamp_depth * 3);
+    dgn_smooth_heights();
+    _swamp_apply_features(2);
+
+    dgn_place_stone_stairs();
+    process_disconnected_zones(0, 0, GXM - 1, GYM - 1, true, DNGN_TREES);
+}
+
+
+#if OLD_SWAMP_LAYOUT
+void dgn_prepare_swamp()
+{
+    dgn_Build_Method += " swamp";
+    dgn_Layout_Type   = "swamp";
+
+    const int margin = 5;
+
+    for (int i = margin; i < (GXM - margin); i++)
+        for (int j = margin; j < (GYM - margin); j++)
+        {
+            // Don't apply Swamp prep in vaults.
+            if (!unforbidden(coord_def(i, j), MMT_VAULT))
+                continue;
+
+            // doors -> floors {dlb}
+            if (grd[i][j] == DNGN_CLOSED_DOOR || grd[i][j] == DNGN_SECRET_DOOR)
+                grd[i][j] = DNGN_FLOOR;
+
+            // floors -> shallow water 1 in 3 times {dlb}
+            if (grd[i][j] == DNGN_FLOOR && one_chance_in(3))
+                grd[i][j] = DNGN_SHALLOW_WATER;
+
+            // walls -> deep/shallow water or remain unchanged {dlb}
+            if (grd[i][j] == DNGN_ROCK_WALL)
+            {
+                const int temp_rand = random2(6);
+
+                if (temp_rand > 0)      // 17% chance unchanged {dlb}
+                {
+                    grd[i][j] = ((temp_rand > 2) ? DNGN_SHALLOW_WATER // 50%
+                                                 : DNGN_DEEP_WATER);  // 33%
+                }
+            }
+        }
+}
+#endif