Added glaciers, and re-organized noise definitions

noises.lua

@@ -0,0 +1,37 @@
+mapgen_rivers.noise_params = {
+	distort_x = {
+		offset = 0,
+		scale = 1,
+		seed = -4574,
+		spread = {x=64, y=32, z=64},
+		octaves = 3,
+		persistence = 0.75,
+		lacunarity = 2,
+	},
+
+	distort_z = {
+		offset = 0,
+		scale = 1,
+		seed = -7940,
+		spread = {x=64, y=32, z=64},
+		octaves = 3,
+		persistence = 0.75,
+		lacunarity = 2,
+	},
+
+	distort_amplitude = {
+		offset = 0,
+		scale = 10,
+		seed = 676,
+		spread = {x=1024, y=1024, z=1024},
+		octaves = 5,
+		persistence = 0.5,
+		lacunarity = 2,
+		flags = "absvalue",
+	},
+
+	heat = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat'),
+	heat_blend = minetest.get_mapgen_setting_noiseparams('mg_biome_np_heat_blend'),
+}
+
+mapgen_rivers.noise_params.heat.offset = mapgen_rivers.noise_params.heat.offset + mapgen_rivers.sea_level*mapgen_rivers.elevation_chill