restored unit support for ellipses -- and added examples/units/ellipse_with_units.py

jdh2358 · jdh2358 · commit f04f5667cf78 · 2007-10-16T13:45:59.000Z
svn path=/trunk/matplotlib/; revision=3954
diff --git a/examples/units/ellipse_with_units.py b/examples/units/ellipse_with_units.py
@@ -0,0 +1,49 @@
+"""
+Compare the ellipse generated with arcs versus a polygonal approximation 
+"""
+from basic_units import cm
+import numpy as npy
+from matplotlib import patches
+from pylab import figure, show
+
+xcenter, ycenter = 0.38*cm, 0.52*cm
+#xcenter, ycenter = 0., 0.
+width, height = 1e-1*cm, 3e-1*cm
+angle = -30
+
+theta = npy.arange(0.0, 360.0, 1.0)*npy.pi/180.0
+x = 0.5 * width * npy.cos(theta)
+y = 0.5 * height * npy.sin(theta)
+
+rtheta = angle*npy.pi/180.
+R = npy.array([
+    [npy.cos(rtheta),  -npy.sin(rtheta)],
+    [npy.sin(rtheta), npy.cos(rtheta)],
+    ])
+
+
+x, y = npy.dot(R, npy.array([x, y]))
+x += xcenter
+y += ycenter
+
+fig = figure()
+ax = fig.add_subplot(211, aspect='auto')
+ax.fill(x, y, alpha=0.2, facecolor='yellow', edgecolor='yellow', linewidth=1, zorder=1)
+
+e1 = patches.Ellipse((xcenter, ycenter), width, height,
+             angle=angle, linewidth=2, fill=False, zorder=2)
+
+ax.add_patch(e1)
+
+ax = fig.add_subplot(212, aspect='equal')
+ax.fill(x, y, alpha=0.2, facecolor='green', edgecolor='green', zorder=1)
+e2 = patches.Ellipse((xcenter, ycenter), width, height,
+             angle=angle, linewidth=2, fill=False, zorder=2)
+
+
+ax.add_patch(e2)
+
+#fig.savefig('ellipse_compare.png')
+fig.savefig('ellipse_compare')
+
+show()
diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
@@ -820,6 +820,8 @@ def get_verts(self):
             [npy.sin(rtheta), npy.cos(rtheta)],
             ])
 
+        x = self.convert_xunits(x)
+        y = self.convert_yunits(y)
 
         x, y = npy.dot(R, npy.array([x, y]))
         x += xcenter
@@ -845,9 +847,6 @@ def draw(self, renderer):
         if self._hatch:
             gc.set_hatch(self._hatch )
 
-        offset = self.offset
-
-        
 
         if not hasattr(renderer, 'draw_path'):
             verbose.report('patches.Ellipse renderer does not support path drawing; falling back on vertex approximation for nonlinear transformation')
@@ -856,15 +855,23 @@ def draw(self, renderer):
         
 
         x, y = self.center
+        x = self.convert_xunits(x)
+        y = self.convert_yunits(y)
+
         theta = self.angle * npy.pi/180.
         T = npy.array([
             [1, 0, x],
             [0, 1, y],
             [0, 0, 1]])
 
+        w, h = self.width/2, self.height/2.
+        w = self.convert_xunits(w)
+        h = self.convert_yunits(h)
+
+        
         S = npy.array([
-            [self.width/2., 0, 0],
-            [0, self.height/2., 0],
+            [w, 0, 0],
+            [0, h, 0],
             [0, 0, 1]])
 
 
