From 2a7c5e4d2e998420a6417156e428e45ce14b2462 Mon Sep 17 00:00:00 2001
From: Shaheen Gandhi <shaheen@fb.com>
Date: Sun, 18 Aug 2013 18:03:12 -0700
Subject: [PATCH] [Helix][perf] Do not process points outside of the coil area

---
 ShaheenGandhi.pde | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/ShaheenGandhi.pde b/ShaheenGandhi.pde
index 5e2c88c..ff6ce2e 100644
--- a/ShaheenGandhi.pde
+++ b/ShaheenGandhi.pde
@@ -106,9 +106,16 @@ class HelixPattern extends SCPattern {
     }
 
     color colorOfPoint(final PVector p) {
+      float t = axis.getTValue(p);
+
+      // For performance reasons, cut out points that are outside of
+      // the tube where the toroidal coil lives.
+      if (abs(PVector.dist(p, axis.getPointAt(t)) - radius) > girth*.5f) {
+        return color(0,0,0);
+      }
+
       // Find the appropriate point for the current rotation
       // of the helix.
-      float t = axis.getTValue(p);
       PVector toroidPoint = pointOnToroidalAxis(t);
 
       // The rotated point represents the middle of the girth of
-- 
2.34.1