From 7fa736fbeb6ad48945ee54f3aee878c2dd4ab836 Mon Sep 17 00:00:00 2001
From: Frederic <frederic@git.blinkenbunt.org>
Date: Sun, 14 Jul 2019 15:05:55 +0200
Subject: [PATCH] indicate stack size with color, some refactoring

---
 lindenmayer-system/lindenmeyer-system.html |  1 -
 lindenmayer-system/lindenmeyer-system.js   | 91 +++++++++++++++-------
 2 files changed, 62 insertions(+), 30 deletions(-)

diff --git a/lindenmayer-system/lindenmeyer-system.html b/lindenmayer-system/lindenmeyer-system.html
index 8ab6f9b..c24bf8c 100644
--- a/lindenmayer-system/lindenmeyer-system.html
+++ b/lindenmayer-system/lindenmeyer-system.html
@@ -272,7 +272,6 @@ function sierpinski(noise) {
      p.scale(80);
      p.translate(new Point(300, 300));
      p.strokeWidth = 1;
-     p.strokeColor = '#ff00ff';
  }
 
 
diff --git a/lindenmayer-system/lindenmeyer-system.js b/lindenmayer-system/lindenmeyer-system.js
index 5c3d708..0391bd4 100644
--- a/lindenmayer-system/lindenmeyer-system.js
+++ b/lindenmayer-system/lindenmeyer-system.js
@@ -27,7 +27,6 @@ function generate(start, rules, iterations) {
                     ruleres = rule[1]();
                 } else if(typeof rule[1] == 'object') {
                     var r = Math.floor(Math.random() * rule[1].length);
-                    console.log(r);
                     ruleres = rule[1][r];
                 }else {
                     ruleres = rule[1];
@@ -46,24 +45,42 @@ function generate(start, rules, iterations) {
         word = newword;
         consumed = newconsumed;
     }
-    
+
     return generate(newword, rules, iterations - 1);
 }
 
 
-function draw_initstate(p, state) {
+function draw_initstate(grp, state) {
     if(!('dir' in state)) {
         state.dir = 0;
         state.turnnoise = 0;
         state.lennoise = 0;
-    }
-    if(!('stepsize' in state)) {
+        state.pos = new paper.Point(0, 0);
+        state.pathstack = [];
         state.stepsize = 1;
+        state.stack = [];
+        state.curpath = null;
     }
-    if(!('curpath' in state)) {
-        p.addChild(new paper.Path());
-        state.curpath = p.lastChild;
-    }
+
+    /*
+      for(let i=0; i<10; i++) {
+      var color = new paper.Color(255,255,255);
+      color.saturation = 1;
+      color.brightness = 1;
+      color.hue = 36 * (10-i); // TODO remove constant
+      state.palette.push(color);
+      }
+    */
+    state.palette = [
+        new paper.Color('#ff0000'),
+        new paper.Color('#ff0000'),
+        new paper.Color('#ff00ff'),
+        new paper.Color('#ff00ff'),
+        new paper.Color('#0000ff'),
+        new paper.Color('#0000ff'),
+        new paper.Color('#00ff00'),
+        new paper.Color('#00ff00'),
+    ];
 }
 
 
@@ -89,18 +106,30 @@ function draw_set_length_noise(level) {
 
 
 function draw_forward(factor=1) {
-    return function(p, state) {
-        draw_initstate(p, state);
-        if(state.curpath.segments.length == 0) {
-            state.curpath.add(new paper.Point(0, 0));
-            console.log('---------------------------');
+    return function(grp, state) {
+        if(state.curpath == null) {
+            var p = new paper.Path();
+            p.add(state.pos);
+            state.curpath = p;
+            // index 0 corresponds to empty state.stack
+            if(state.pathstack[state.stack.length] == null) {
+                var cp = new paper.CompoundPath();
+                cp.addChild(p);
+                cp.strokeColor = state.palette[state.stack.length];
+                state.pathstack[state.stack.length] = cp;
+                grp.addChild(cp);
+            }
+            state.pathstack[state.stack.length].addChild(p);
         }
+
         var lastp = state.curpath.segments[state.curpath.segments.length - 1].point;
         var noise = 1 + (Math.random() - 0.5) * state.lennoise;
         state.curpath.add(lastp.add(new paper.Point(
               Math.sin(state.dir) * state.stepsize * factor * noise,
               Math.cos(state.dir) * state.stepsize * factor * noise
         )));
+        var lastseg = state.curpath.segments[state.curpath.segments.length - 1];
+        state.pos = lastseg.point;
     };
 }
 
@@ -112,7 +141,6 @@ function draw_stepsize_mul(factor) {
         } else {
             var f = factor;
         }
-        draw_initstate(p, state);
         state.stepsize *= f;
     };
 }
@@ -120,7 +148,6 @@ function draw_stepsize_mul(factor) {
 
 function draw_turn(angle) {
     return function(p, state) {
-        draw_initstate(p, state);
         state.dir += angle;
     };
 }
@@ -128,7 +155,6 @@ function draw_turn(angle) {
 
 function draw_angle_turn(fac) {
     return function(p, state) {
-        draw_initstate(p, state);
         var a = state.angle * (1 + (Math.random() - 0.5) * state.turnnoise);
         state.dir += a * fac;
     };
@@ -150,38 +176,45 @@ function draw_angle_add(delta) {
 
 
 function draw_state_push() {
-    return function(p, state) {
-        if(typeof state.stack == 'undefined') {
-            state.stack = new Array();
-        }
+    return function(grp, state) {
         state.stack.push({
-            pos: state.curpath.segments[state.curpath.segments.length - 1].point,
+            pos: state.pos,
             dir: state.dir,
             stepsize: state.stepsize,
         });
+        state.curpath = null;
+        /*
+        if(state.palette[state.stack.length] !=
+           state.palette[state.stack.length - 1]) {
+            p.addChild(new paper.Path());
+            state.curpath = p.lastChild;
+            state.curpath.add(pos);
+            state.curpath.strokeColor = state.palette[state.stack.length];
+        }
+        */
     };
 }
 
 
 function draw_state_pop() {
-    return function(p, state) {
+    return function(grp, state) {
         var s = state.stack.pop();
         state.dir = s.dir;
         state.stepsize = s.stepsize;
-        p.addChild(new paper.Path());
-        state.curpath = p.lastChild;
-        state.curpath.add(s.pos);
+        state.pos = s.pos;
+        state.curpath = null;
     };
 }
 
 
 function draw(word, actions) {
-    var p = new paper.CompoundPath();
+    var grp = new paper.Group();
     var state = {};
+    draw_initstate(grp, state);
     for(let w of word) {
         if(w in actions) {
-            actions[w](p, state);
+            actions[w](grp, state);
         }
     }
-    return p;
+    return grp;
 }