D627: Memory usage optimization for the compositor.

The compostor used a fixed size of 4 floats to hold pixel data. this
patch will select size of a pixel based on its type.
It uses 1 float for Value, 3 float for vector and 4 floats for color
data types.

When benchmarking on shots (opening shot of caminandes) we get a
reduction of memory of 30% and a tiny speedup as less data
transformations needs to take place (but these are negligable.

More information of the patch can be found on
https://developer.blender.org/D627 and
http://wiki.blender.org/index.php/Dev:Ref/Proposals/Compositor2014_p1.1_TD

Developers: jbakker & mdewanchand
Thanks for Sergey for his indept review.

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/compositor/operations/COM_QualityStepHelper.cpp b/source/blender/compositor/operations/COM_QualityStepHelper.cpp
index d99d6f28eff..4d9c15f9747 100644
--- a/source/blender/compositor/operations/COM_QualityStepHelper.cpp
+++ b/source/blender/compositor/operations/COM_QualityStepHelper.cpp
@@ -37,15 +37,15 @@ void QualityStepHelper::initExecution(QualityHelper helper)
 				case COM_QUALITY_HIGH:
 				default:
 					this->m_step = 1;
-					this->m_offsetadd = 4;
+					this->m_offsetadd = 1;
 					break;
 				case COM_QUALITY_MEDIUM:
 					this->m_step = 2;
-					this->m_offsetadd = 8;
+					this->m_offsetadd = 2;
 					break;
 				case COM_QUALITY_LOW:
 					this->m_step = 3;
-					this->m_offsetadd = 12;
+					this->m_offsetadd = 3;
 					break;
 			}
 			break;