From: Daid <daid303@gmail.com>
Date: Sat, 28 Jul 2012 09:04:04 +0000 (+0200)
Subject: Faster generation of normals with numpy.
X-Git-Tag: 12.08~15
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=c92cc07afd8af81434d1c46867136d481e0ed833;p=cura.git

Faster generation of normals with numpy.
---

diff --git a/Cura/util/mesh.py b/Cura/util/mesh.py
index 128d362e..dc01198c 100644
--- a/Cura/util/mesh.py
+++ b/Cura/util/mesh.py
@@ -63,13 +63,14 @@ class mesh(object):
 			mat = numpy.array([mat[0],mat[2],mat[1]])
 		self.vertexes = (numpy.matrix(self.origonalVertexes, copy = False) * numpy.matrix(mat)).getA()
 
-		for i in xrange(0, len(self.origonalVertexes), 3):
-			v1 = self.vertexes[i]
-			v2 = self.vertexes[i+1]
-			v3 = self.vertexes[i+2]
-			self.normal[i/3] = numpy.cross((v2 - v1), (v3 - v1))
-			self.normal[i/3] /= (self.normal[i/3] * self.normal[i/3]).sum()
-
+		tris = self.vertexes.reshape(self.vertexCount / 3, 3, 3)
+		normals = numpy.cross( tris[::,1 ] - tris[::,0]  , tris[::,2 ] - tris[::,0] )
+		lens = numpy.sqrt( normals[:,0]**2 + normals[:,1]**2 + normals[:,2]**2 )
+		normals[:,0] /= lens
+		normals[:,1] /= lens
+		normals[:,2] /= lens
+		self.normal = normals
+		
 		self.getMinimumZ()
 
 	def splitToParts(self):