Remove import of chroma.io.root in the __init__.py module and also the

global import of RootReader in the chroma.camera module.

Bringing in ROOT adds 14 seconds to the import time, which really
sucks if you don't need it.

2 files changed, 3 insertions, 2 deletions

diff --git a/chroma/__init__.py b/chroma/__init__.py
index c3f4243..b409871 100644
--- a/chroma/__init__.py
+++ b/chroma/__init__.py
@@ -4,7 +4,6 @@ except ImportError:
     pass # Allow chroma usage when pygame not present
 from chroma import geometry
 from chroma import event
-from chroma.io import root
 from chroma import generator
 from chroma.generator import constant_particle_gun
 from chroma import gpu
diff --git a/chroma/camera.py b/chroma/camera.py
index 4929519..09463d1 100644
--- a/chroma/camera.py
+++ b/chroma/camera.py
@@ -17,7 +17,6 @@ from chroma.geometry import Mesh, Solid, Geometry, vacuum
 from chroma.transform import rotate, make_rotation_matrix
 from chroma.sample import uniform_sphere
 from chroma.project import from_film
-from chroma.io.root import RootReader
 from chroma import make
 from chroma import gpu
 
@@ -686,6 +685,9 @@ class EventViewer(Camera):
 
     def __init__(self, geometry, filename, **kwargs):
         Camera.__init__(self, geometry, **kwargs)
+        # This is really slow, so we do it here in the constructor to 
+        # avoid slowing down the import of this module
+        from chroma.io.root import RootReader
         self.rr = RootReader(filename)
         self.display_mode = EventViewer.CHARGE
         self.sum_mode = False