From aea6a53cf26a5feb09f5a496b098195f60f29b81 Mon Sep 17 00:00:00 2001
From: Fr3deric <frederic@localhost.localdomain>
Date: Sun, 3 Mar 2019 19:50:21 +0100
Subject: [PATCH] add new crown shape: ellipse

---
 baumgen.js | 62 ++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 55 insertions(+), 7 deletions(-)

diff --git a/baumgen.js b/baumgen.js
index 787d274..b81fee7 100644
--- a/baumgen.js
+++ b/baumgen.js
@@ -7,23 +7,29 @@ function gen_tree(pos) {
 
     baum.length = (20 + Math.random() * 20);
 
-    var shapernd = Math.random();
-    if(shapernd < 0.5) {
+    var shapernd = Math.random() * 3;
+    if(shapernd < 1) {
         baum.crown = new KiteCrown(
             70 + Math.random() * 30,
             0.4 + Math.random() * 0.2,
             {bisect: 0.2 + Math.random() * 0.2},
-        )
-    } else {
+        );
+    } else if(shapernd < 2) {
         baum.crown = new TriangleCrown(
             70 + Math.random() * 30,
             0.4 + Math.random() * 0.2,
-        )
+        );
+    } else {
+        baum.crown = new EllipseCrown(
+            70 + Math.random() * 30,
+            0.4 + Math.random() * 0.2,
+            {bisect: 0.1 + Math.random() * 0.4},
+        );
     }
 
     baum.angle = Math.PI / 2; // + Math.random() * 0.2 - 0.1;
 
-    if((baum.crown.shape == "kite") && (Math.random() < 0.5)) {
+    if((baum.crown.shape != "triangle") && (Math.random() < 0.5)) {
         var crown = baum.crown.clone();
         crown.length *= 0.4;
         var b = {
@@ -83,7 +89,7 @@ class Crown {
 
 
 class KiteCrown extends Crown {
-    constructor(length, width, {bisect = 0.3}) {
+    constructor(length, width, {bisect = 0.3}={}) {
         super(length, width, 'kite');
         this.bisect = bisect;
     }
@@ -138,6 +144,48 @@ class TriangleCrown extends Crown {
 }
 
 
+class EllipseCrown extends Crown {
+    constructor(length, width, {bisect = 0.5}={}) {
+        super(length, width, 'ellipse');
+        this.bisect = bisect;
+    }
+
+    clone() {
+        return new EllipseCrown(this.length, this.width, {bisect: this.bisect});
+    }
+
+    draw(branch, bvec, cpos) {
+        this.undraw();
+        var cvec = bvec.multiply(1/bvec.length * this.length);
+        var bswidth = this.length * this.width;
+        var bsvec = new Point(Math.sin(branch.angle) * bswidth / 2,
+                              Math.cos(branch.angle) * bswidth / 2);
+        this._path = new Path();
+        this._path.strokeColor = 'black';
+        this._path.fillColor = 'white';
+        this._path.strokeWidth = 2;
+        this._path.closed = true;
+        var cmid = cpos.add(cvec.multiply(this.bisect));
+        this._path.add(new Segment(cpos,
+                                   bsvec.multiply(0.5),
+                                   bsvec.multiply(-0.5),
+                                   ));
+        this._path.add(new Segment(cmid.subtract(bsvec),
+                                   bvec.multiply(-0.5),
+                                   bvec.multiply(0.5),
+                                   ));
+        this._path.add(new Segment(cpos.add(cvec),
+                                   bsvec.multiply(-0.5),
+                                   bsvec.multiply(0.5),
+                                   ));
+        this._path.add(new Segment(cmid.add(bsvec),
+                                   bvec.multiply(0.5),
+                                   bvec.multiply(-0.5),
+                                   ));
+    }
+}
+
+
 class Branch {
     constructor(data, parentBranch=null) {
         //this.parentBranch = parentBranch;