tree f31aaadd1c18fe15ab9a63ba221693fb77507161
parent 2298938cef8d5aa2211ef08e27553354918e5554
author ztenghui <ztenghui@google.com> 1412360471 -0700
committer ztenghui <ztenghui@google.com> 1412375453 -0700

Use float instead of double to increase spot shadow perf

This is helping spot shadow for 15%-20% increase.
With the new algorithm, we are less sensitive to the floating point error.

b/16712006

Change-Id: Ie30a6ce01e73d56054a0cf65a84549454339a7fd