From 2979b66351bb819d3e615730b8922d16c92e73eb Mon Sep 17 00:00:00 2001
From: Tobias Berger <tobi.berger13@gmail.com>
Date: Mon, 5 Sep 2022 21:11:36 +0200
Subject: [PATCH] Tweak rainfall generation

fd6c7dfe5931f5d183c939f48c515ad6bf92d1b1
---
 Cargo.lock        |  1 -
 Cargo.toml        |  2 +-
 save/src/world.rs | 22 ++++++++++++++++------
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 43cc013..de93e3e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -371,7 +371,6 @@ dependencies = [
  "bevy_ptr",
  "bevy_reflect",
  "bevy_render",
- "bevy_scene",
  "bevy_sprite",
  "bevy_tasks",
  "bevy_text",
diff --git a/Cargo.toml b/Cargo.toml
index 1c6f8bb..0ceca43 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,7 +5,7 @@ edition = "2021"
 
 [features]
 debug = ["save/debug"]
-render = ["bevy/bevy_asset", "bevy/bevy_winit", "bevy/bevy_scene", "bevy/render", "save/render"]
+render = ["bevy/bevy_asset", "bevy/bevy_winit", "bevy/render", "save/render"]
 default = ["render"]
 
 [dependencies.save]
diff --git a/save/src/world.rs b/save/src/world.rs
index 6965899..2e15f84 100644
--- a/save/src/world.rs
+++ b/save/src/world.rs
@@ -280,12 +280,12 @@ impl World {
     }
 
     fn generate_rainfall_alt(&mut self) -> Result<(), CartesianError> {
-        const MAX_CYCLES: u8 = 25;
+        let max_cycles = self.width;
 
-        const ACCUMULATED_RAIN_FACTOR: f32 = 2.0;
-        const RAINFALL_FACTOR: f32 = 0.1;
+        const ACCUMULATED_RAIN_FACTOR: f32 = 0.002;
+        const RAINFALL_FACTOR: f32 = 0.025;
 
-        for _ in 0..MAX_CYCLES {
+        for _ in 0..max_cycles {
             for x in 0..self.width {
                 let prev_x = (x + 1) % self.width;
 
@@ -302,9 +302,19 @@ impl World {
 
                     let prev_cell = self.terrain[y as usize][prev_x as usize];
 
+                    let altitude_difference = f32::max(
+                        0.0,
+                        f32::max(0.0, cell.altitude) - f32::max(0.0, prev_cell.altitude),
+                    );
+                    let final_rain_factor = f32::min(
+                        0.1,
+                        RAINFALL_FACTOR + (altitude_difference / Self::MAX_ALTITUDE) * 0.1,
+                    );
+
                     cell.rain_accumulated += prev_cell.rain_accumulated;
-                    cell.rainfall += cell.rain_accumulated * RAINFALL_FACTOR;
-                    cell.rain_accumulated -= cell.rainfall;
+                    let rain_accumulated = cell.rain_accumulated * final_rain_factor;
+                    cell.rainfall += rain_accumulated / (width_factor + 0.001);
+                    cell.rain_accumulated -= rain_accumulated;
 
                     cell.rain_accumulated = f32::max(cell.rain_accumulated, 0.0);