Changes between Version 9 and Version 10 of Examples/Brain

Timestamp:

04/11/17 13:48:24 (7 years ago)

Author:

Herwig Zilken

Comment:

--

Examples/Brain

@@ -231 +231 @@
 }}}
 
-Resulting movie sniplet:
+Resulting movie snippet:
 [raw-attachment:orbit.wmv Camera Orbit]
 
@@ -278 +278 @@
   animationScene.GoToNext()
 }}}
-Resulting movie sniplet:
+Resulting movie snippet:
 [raw-attachment:camera_flight.wmv Camera Flight]
+
+=== Animation of Color and Opacity
+As seen above, the color and opacity maps are stored in Python as lists.
+Given a start and a end color/opacity list, it is very easy to implement a small python funtion to calculate a linear interpolation. In the following example, images for interpolated opacity values are rendered.
+{{{
+#!python
+# t: timestep, in range [0.0, 1.0]
+def interpolate(t, list1, list2):
+  if len(list1) != len(list2):
+    return []
+  result = []
+  for i in range(len(list1)):
+    diff = list2[i]-list1[i]
+    result.append(list1[i] + diff*t)
+  return result
+
+
+# start opacity list, t=0.0
+pLIPWF1 = [0.0, 0.0, 0.5, 0.0,   0.0, 0.0, 0.5, 0.0,  254.0, 1.0, 0.5, 0.0]
+#end opacity list, t=1.0
+pLIPWF2 = [0.0, 0.0, 0.5, 0.0,  25.0, 0.0, 0.5, 0.0,  254.0, 1.0, 0.5, 0.0]
+
+camera.SetPosition(0.0, 0.0, 1.488)
+camera.SetFocalPoint(0.0, 0.0, 0.0)
+camera.SetViewUp(-1.0, 0.0, 0.0)
+imageNum = 0
+
+for i in range(30):
+  pLIPWF.Points = interpolate (i/29.0, pLIPWF1, pLIPWF2)
+  print ("opacity interpolation: rendering image %04d" % (imageNum))
+  Render()
+  WriteImage("opacity_image_%04d.png" % (imageNum))
+  imageNum = imageNum + 1
+
+}}}
+Resulting movie snippet:
+[raw-attachment:opacity.wmv Animation of opacity]
+