From 1fb449fdf6025ed4826b79107295e79ececc946c Mon Sep 17 00:00:00 2001
From: Justin Lin <justin.sdk@gmail.com>
Date: Fri, 27 May 2022 09:10:35 +0800
Subject: [PATCH] refactor and add smooth params

---
 examples/differential_line_growth.scad        | 25 ++++++++++++-------
 .../_impl/_differential_line_growth.scad      | 22 +++++++++-------
 2 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/examples/differential_line_growth.scad b/examples/differential_line_growth.scad
index a84eb683..938eb006 100644
--- a/examples/differential_line_growth.scad
+++ b/examples/differential_line_growth.scad
@@ -1,18 +1,25 @@
 use <shape_circle.scad>;
 use <experimental/differential_line_growth.scad>;
-    
+use <midpt_smooth.scad>;
+
 $fn = 24;
-r = 20;
-times = 50;
+r = 10;
+times = 80;
 thickness = 2;
+smooth = true;
+smooth_times = 2;
 node_option = [
-    0.5,    // maxForce 
-    0.7,    // maxSpeed
-    12,     // separationDistance
-    1.5,    // separationCohesionRatio 
-    10      // maxEdgeLength
+    0.4,    // maxForce 
+    0.5,    // maxSpeed
+    5,      // separationDistance
+    1.2,    // separationCohesionRatio 
+    4       // maxEdgeLength
 ];
 
 init_shape = shape_circle(r);
+poly = differential_line_growth(init_shape, node_option, times);
+
 linear_extrude(thickness)
-    polygon(differential_line_growth(init_shape, node_option, times));
+    polygon(
+        smooth ? midpt_smooth(poly, smooth_times, true) : poly 
+    );
diff --git a/src/experimental/_impl/_differential_line_growth.scad b/src/experimental/_impl/_differential_line_growth.scad
index 7b673760..d5a61446 100644
--- a/src/experimental/_impl/_differential_line_growth.scad
+++ b/src/experimental/_impl/_differential_line_growth.scad
@@ -89,18 +89,22 @@ function updateAllSeperation(allSeperation, allSeperationFrom_i_1, leng, n) = [
 function differentiate(nodes, leng) = 
     [
         for(i = 0,
-            allSep = [for(i = [0:leng - 1]) ZERO_VT],
-            allSeperationFrom_i_1 = allSeperationFrom(nodes, leng, nodes[i], i + 1); 
-            i < leng;
-            allSep = updateAllSeperation(allSep, allSeperationFrom_i_1, leng, i + 1), 
+            j = 1,
+            allSeperationFrom_i_1 = allSeperationFrom(nodes, leng, nodes[i], j),
+            allSep = [ZERO_VT, each -allSeperationFrom_i_1],
+            running = i < leng; 
+            running; 
             i = i + 1,
-            allSeperationFrom_i_1 = i < leng ? allSeperationFrom(nodes, leng, nodes[i], i + 1) : undef
+            j = j + 1,
+            running = i < leng,
+            allSeperationFrom_i_1 = running ? allSeperationFrom(nodes, leng, nodes[i], j) : undef,
+            allSep = running ? updateAllSeperation(allSep, allSeperationFrom_i_1, leng, j) : undef
         )
-        let(
-            seperation_i = sum([allSep[i], each allSeperationFrom_i_1]),
-            cohesion_i = cohesion(nodes, leng, i)
+        applyForceTo(
+            nodes[i], 
+            sum([allSep[i], each allSeperationFrom_i_1]), 
+            cohesion(nodes, leng, i)
         )
-        applyForceTo(nodes[i], seperation_i, cohesion_i)
     ];
     
 function _differential_line_growth(nodes) =