From 01cc1eec30b51832baf610267b9262cc3a8c1a44 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C3=A9sz=C3=A1ros=20Gergely?= <monk@geotronic.hu>
Date: Sun, 15 Aug 2021 04:41:59 +0200
Subject: [PATCH] effective distanceScale

---
 index.html                 | 20 ++++++++++++++------
 main.js                    |  1 +
 modules/river-generator.js |  8 ++++----
 modules/ui/submap.js       |  4 ++--
 modules/ui/units-editor.js |  2 ++
 5 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/index.html b/index.html
index 6fc0083b..a92f5148 100644
--- a/index.html
+++ b/index.html
@@ -3506,14 +3506,22 @@
     <div id="submapOptionsDialog" style="display: none; max-width:300px;" class="dialog">
       <p style="font-style: italic; color: red; font-weight:bold;">Original map will be destroyed! Don't forget to save your work!</p>
       <p>Population rate (Units editor -> population) and map pixel size will
-        be automatically update according to the current scale factor. Options are interpreted as usual.</p>
-      <hl />
+        be automatically updated according to the current scale factor. If you'd like
+        to generate a new parent-map, <b>don't forget to reset them!</b> Options are interpreted as usual.</p>
+      <hr />
       <div data-tip="All small cities of the parent map will be promoted to Capitals." >
-      <input id="submapPromoteTown" class="checkbox" type="checkbox">
-      <label for="submapPromoteTown" class="checkbox-label">Promote towns to cities.</label>
-      <input id="submapDepressRivers" class="checkbox" type="checkbox">
-      <label for="submapDepressRivers" class="checkbox-label">Errode riverbeds.</label>
+        <input id="submapPromoteTown" class="checkbox" type="checkbox">
+        <label for="submapPromoteTown" class="checkbox-label">Promote towns to cities.</label>
       </div>
+      <div data-tip="Rivers on the parent map errode land (helps to get similar river network.)" >
+        <input id="submapDepressRivers" class="checkbox" type="checkbox">
+        <label for="submapDepressRivers" class="checkbox-label">Errode riverbeds.</label>
+      </div>
+      <div data-tip="Add lakes in depressions. (Can be very slow on big landmass!)" >
+        <input id="submapAddLakeInDepression" class="checkbox" type="checkbox">
+        <label for="submapAddLakeInDepression" class="checkbox-label">Add lakes in depressions.</label>
+      </div>
+      <hr/>
       <button id="start" data-tip="Start submap resampling" class="options glow" onclick="generateSubmap()">Generate</button>
     </div>
 
diff --git a/main.js b/main.js
index 9b0ef9b8..f3845190 100644
--- a/main.js
+++ b/main.js
@@ -153,6 +153,7 @@ let mapCoordinates = {}; // map coordinates on globe
 options.winds = [225, 45, 225, 315, 135, 315]; // default wind directions
 
 let populationRate = +document.getElementById("populationRateInput").value;
+let distanceScale = +document.getElementById("distanceScaleInput").value;
 let urbanization = +document.getElementById("urbanizationInput").value;
 
 applyStoredOptions();
diff --git a/modules/river-generator.js b/modules/river-generator.js
index a17cff87..6e2ff7ef 100644
--- a/modules/river-generator.js
+++ b/modules/river-generator.js
@@ -31,14 +31,14 @@ window.Rivers = (function () {
     TIME && console.timeEnd("generateRivers");
 
     function drainWater() {
-      const MIN_FLUX_TO_FORM_RIVER = 30;
+      const MIN_FLUX_TO_FORM_RIVER = 10 * distanceScale;
       const prec = grid.cells.prec;
-      const area = pack.cells.area;
+      const area = c => pack.cells.area[c] * distanceScale * distanceScale;
       const land = cells.i.filter(i => h[i] >= 20).sort((a, b) => h[b] - h[a]);
       const lakeOutCells = Lakes.setClimateData(h);
 
       land.forEach(function (i) {
-        cells.fl[i] += prec[cells.g[i]] * area[i] / 100; // add flux from precipitation
+        cells.fl[i] += prec[cells.g[i]] * area(i) / 1000; // add flux from precipitation
 
         // create lake outlet if lake is not in deep depression and flux > evaporation
         const lakes = lakeOutCells[i] ? features.filter(feature => i === feature.outCell && feature.flux > feature.evaporation) : [];
@@ -166,7 +166,7 @@ window.Rivers = (function () {
         const mouth = riverCells[riverCells.length - 2];
         const parent = riverParents[key] || 0;
 
-        const widthFactor = !parent || parent === riverId ? 1.2 : 1;
+        const widthFactor = (!parent || parent === riverId ? 3.6 : 3) / distanceScale;
         const meanderedPoints = addMeandering(riverCells);
         const discharge = cells.fl[mouth]; // m3 in second
         const length = rn(getApproximateLength(meanderedPoints), 2);
diff --git a/modules/ui/submap.js b/modules/ui/submap.js
index 6a99461b..d89aa4df 100644
--- a/modules/ui/submap.js
+++ b/modules/ui/submap.js
@@ -33,8 +33,8 @@ const generateSubmap = debounce(async function () {
   }
 
   // fix scale
-  distanceScaleInput.value = distanceScaleOutput.value = distanceScaleOutput.value / scale;
-  populationRateInput.value = populationRateOutput.value = populationRateOutput.value / scale;
+  distanceScale = distanceScaleInput.value = distanceScaleOutput.value = distanceScaleOutput.value / scale;
+  populationRate = populationRateInput.value = populationRateOutput.value = populationRateOutput.value / scale;
   customization = 0;
 
   undraw();
diff --git a/modules/ui/units-editor.js b/modules/ui/units-editor.js
index 54571191..34725e33 100644
--- a/modules/ui/units-editor.js
+++ b/modules/ui/units-editor.js
@@ -55,6 +55,7 @@ function editUnits() {
   }
 
   function changeDistanceScale() {
+    distanceScale = +document.getElementById("distanceScaleInput").value;
     drawScaleBar();
     calculateFriendlyGridSize();
   }
@@ -95,6 +96,7 @@ function editUnits() {
 
   function restoreDefaultUnits() {
     // distanceScale
+    distanceScale = 3;
     document.getElementById("distanceScaleOutput").value = 3;
     document.getElementById("distanceScaleInput").value = 3;
     unlock("distanceScale");