From 19a0a725459a2679b6e7392350f771e04813528f Mon Sep 17 00:00:00 2001
From: Solara570 <thuxuzhang@163.com>
Date: Wed, 20 Dec 2017 20:31:02 +0800
Subject: [PATCH] 3D Hilbert Curve Implemented

---
 topics/fractals.py | 41 +++++++++++++++++++++++++++++++----------
 1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/topics/fractals.py b/topics/fractals.py
index 93825822..7a43ffab 100644
--- a/topics/fractals.py
+++ b/topics/fractals.py
@@ -423,18 +423,39 @@ class HilbertCurve(SelfSimilarSpaceFillingCurve):
 
 class HilbertCurve3D(SelfSimilarSpaceFillingCurve):
     CONFIG = {
-        "offsets" : [ 
-           LEFT+DOWN+OUT,
-           LEFT+UP+OUT,
-           LEFT+UP+IN,
-           LEFT+DOWN+IN,
-           RIGHT+DOWN+IN,                                               
-           RIGHT+UP+IN,
-           RIGHT+UP+OUT,
-           RIGHT+DOWN+OUT,
+        "offsets" : [
+            RIGHT+DOWN+IN,
+            LEFT+DOWN+IN,
+            LEFT+DOWN+OUT,
+            RIGHT+DOWN+OUT,
+            RIGHT+UP+OUT,
+            LEFT+UP+OUT,
+            LEFT+UP+IN,
+            RIGHT+UP+IN,
         ],
-        "offset_to_rotation_axis" : {}#TODO
+        "offset_to_rotation_axis_and_angle" : {
+            str(RIGHT+DOWN+IN)  : (LEFT+UP+OUT  , 2*np.pi/3),
+            str(LEFT+DOWN+IN)   : (RIGHT+DOWN+IN, 2*np.pi/3),
+            str(LEFT+DOWN+OUT)  : (RIGHT+DOWN+IN, 2*np.pi/3),
+            str(RIGHT+DOWN+OUT) : (UP           , np.pi    ),
+            str(RIGHT+UP+OUT)   : (UP           , np.pi    ),
+            str(LEFT+UP+OUT)    : (LEFT+DOWN+OUT, 2*np.pi/3),
+            str(LEFT+UP+IN)     : (LEFT+DOWN+OUT, 2*np.pi/3),
+            str(RIGHT+UP+IN)    : (RIGHT+UP+IN  , 2*np.pi/3),
+        },
     }
+    # Rewrote transform method to include the rotation angle
+    def transform(self, points, offset):
+        copy = np.array(points)
+        copy = rotate(
+            copy, 
+            axis = self.offset_to_rotation_axis_and_angle[str(offset)][0],
+            angle = self.offset_to_rotation_axis_and_angle[str(offset)][1],
+        )
+        copy /= self.scale_factor,
+        copy += offset*self.radius*self.radius_scale_factor
+        return copy
+
 
 class PeanoCurve(SelfSimilarSpaceFillingCurve):
     CONFIG = {