Finished icecap generation and added option to write out an ice map.

Author: tcld

worldengine/cli/main.py

@@ -7,7 +7,8 @@
 from worldengine.common import array_to_matrix, set_verbose, print_verbose
 from worldengine.draw import draw_ancientmap_on_file, draw_biome_on_file, draw_ocean_on_file, \
     draw_precipitation_on_file, draw_grayscale_heightmap_on_file, draw_simple_elevation_on_file, \
-    draw_temperature_levels_on_file, draw_riversmap_on_file, draw_scatter_plot_on_file, draw_satellite_on_file
+    draw_temperature_levels_on_file, draw_riversmap_on_file, draw_scatter_plot_on_file, \
+    draw_satellite_on_file, draw_icecaps_on_file
 from worldengine.plates import world_gen, generate_plates_simulation
 from worldengine.imex import export
 from worldengine.step import Step
@@ -87,6 +88,10 @@ def draw_satellite_map(world, filename):
     draw_satellite_on_file(world, filename)
     print("+ satellite map generated in '%s'" % filename)
 
+def draw_icecaps_map(world, filename):
+    draw_icecaps_on_file(world, filename)
+    print("+ icecap map generated in '%s'" % filename)
+
 def generate_plates(seed, world_name, output_dir, width, height,
                     num_plates=10):
     """
@@ -322,9 +327,10 @@ def main():
                                default=True)
     g_generate.add_argument('--scatter', dest='scatter_plot',
                             action="store_true", help="generate scatter plot")
-
     g_generate.add_argument('--sat', dest='satelite_map',
                             action="store_true", help="generate satellite map")
+    g_generate.add_argument('--ice', dest='icecaps_map',
+                            action="store_true", help="generate ice caps map")
 
     # -----------------------------------------------------
     g_ancient_map = parser.add_argument_group(
@@ -480,6 +486,7 @@ def main():
         print(' black and white maps : %s' % args.black_and_white)
         print(' step                 : %s' % step.name)
         print(' greyscale heightmap  : %s' % args.grayscale_heightmap)
+        print(' icecaps heightmap    : %s' % args.icecaps_map)
         print(' rivers map           : %s' % args.rivers_map)
         print(' scatter plot         : %s' % args.scatter_plot)
         print(' satellite map        : %s' % args.satelite_map)
@@ -543,7 +550,10 @@ def main():
             '%s/%s_scatter.png' % (args.output_dir, world_name))    
         if args.satelite_map:
             draw_satellite_map(world,
-            '%s/%s_satellite.png' % (args.output_dir, world_name))    
+            '%s/%s_satellite.png' % (args.output_dir, world_name))
+        if args.icecaps_map:
+            draw_icecaps_map(world,
+            '%s/%s_icecaps.png' % (args.output_dir, world_name))
 
     elif operation == 'plates':
         print('')  # empty line

worldengine/draw.py

@@ -395,6 +395,7 @@ def draw_satellite(world, target):
             target.set_pixel(x, y, (r, g, b, 255))
 
     # Paint frozen areas.
+    ice_color_variation = int(30)  # 0 means perfectly white ice; must be in [0, 255]; only affects R- and G-channel
     for y in range(world.height):
         for x in range(world.width):
             if world.icecap[y, x] > 0.0:
@@ -817,3 +818,8 @@ def draw_satellite_on_file(world, filename):
     img = PNGWriter.rgba_from_dimensions(world.width, world.height, filename)
     draw_satellite(world, img)
     img.complete()
+
+
+def draw_icecaps_on_file(world, filename):
+    img = PNGWriter.grayscale_from_array(world.icecap, filename, scale_to_range=True)
+    img.complete()

worldengine/simulations/icecap.py

@@ -15,8 +15,6 @@ def is_applicable(world):
 
     def execute(self, world, seed):
         world.icecap = self._calculate(world, seed)
-        print("icecap written!!!!!!!!")
-        print(hasattr(world, 'icecap'))
 
     @staticmethod
     def _calculate(world, seed):
@@ -31,14 +29,14 @@ def _calculate(world, seed):
         temperature = world.temperature['data']
 
         # primary constants (could be used as global variables at some point); all values should be in [0, 1]
-        max_freeze_percentage = 0.50  # only the coldest x% of the cold area will freeze (0 = no ice, 1 = all ice)
-        freeze_chance_window = 0.10  # the warmest x% of freezable area won't completely freeze (RNG decides)
+        max_freeze_percentage = 0.60  # only the coldest x% of the cold area will freeze (0 = no ice, 1 = all ice)
+        freeze_chance_window = 0.20  # the warmest x% of freezable area won't completely freeze (RNG decides)
         surrounding_tile_influence = 0.5  # chance-modifier to freeze a slightly warm tile when neighbors are frozen
 
         # secondary constants
         temp_min = temperature.min()  # coldest spot in the world
         freeze_threshold = world.temperature['thresholds'][0][1]  # upper temperature-limit for freezing effects
-        # Cold biomes:
+        # Cold biomes: TODO: find and pick most appropriate threshold
         #    polar: self.temperature['thresholds'][0][1]
         #   alpine: self.temperature['thresholds'][1][1]
         #   boreal: self.temperature['thresholds'][2][1]
@@ -65,13 +63,14 @@ def _calculate(world, seed):
                         # *can* freeze for freeze_chance_threshold < t < freeze_threshold
 
                         # count number of frozen/solid tiles around this one
-                        surr_tiles = solid_map[max(y-1, 0):min(y+2, world.height), max(x-1, 0):min(x+2, world.width)]
-                        chance_mod = numpy.count_nonzero(surr_tiles)
-                        chance_mod -= 1 if solid_map[y, x] else 0  # remove center-tile (i.e. the current tile)
-
-                        # map amount of tiles to chance-modifier, [-1.0, 1.0]
-                        chance_mod = numpy.interp(chance_mod, [0, 4, 8], [-1.0, 0.0, 1.0])  # 0 to 8 tiles are frozen
-                        chance += chance_mod * surrounding_tile_influence
+                        if 0 < x < world.width - 1 and 0 < y < world.height - 1:  # exclude borders
+                            surr_tiles = solid_map[y-1:y+2, x-1:x+2]
+                            chance_mod = numpy.count_nonzero(surr_tiles)
+                            chance_mod -= 1 if solid_map[y, x] else 0  # remove center-tile (i.e. the current tile)
+
+                            # map amount of tiles to chance-modifier, [-1.0, 1.0]
+                            chance_mod = numpy.interp(chance_mod, [0, surr_tiles.size - 1], [-1.0, 1.0])
+                            chance += chance_mod * surrounding_tile_influence
 
                         if rng.rand() <= chance:  # always freeze for chance >= 1.0, never for <= 0.0
                             solid_map[y, x] = True  # mark tile as frozen