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, 16 insertions, 13 deletions

diff --git a/source/blender/compositor/operations/COM_VariableSizeBokehBlurOperation.cpp b/source/blender/compositor/operations/COM_VariableSizeBokehBlurOperation.cpp
index 4b81001fdab..4809efd7436 100644
--- a/source/blender/compositor/operations/COM_VariableSizeBokehBlurOperation.cpp
+++ b/source/blender/compositor/operations/COM_VariableSizeBokehBlurOperation.cpp
@@ -137,30 +137,33 @@ void VariableSizeBokehBlurOperation::executePixel(float output[4], int x, int y,
 		copy_v4_fl(multiplier_accum, 1.0f);
 		float size_center = tempSize[0] * scalar;
 		
-		const int addXStep = QualityStepHelper::getStep() * COM_NUMBER_OF_CHANNELS;
-		
+		const int addXStepValue = QualityStepHelper::getStep();
+		const int addYStepValue = addXStepValue;
+		const int addXStepColor = addXStepValue * COM_NUM_CHANNELS_COLOR;
+
 		if (size_center > this->m_threshold) {
-			for (int ny = miny; ny < maxy; ny += QualityStepHelper::getStep()) {
+			for (int ny = miny; ny < maxy; ny += addYStepValue) {
 				float dy = ny - y;
-				int offsetNy = ny * inputSizeBuffer->getWidth() * COM_NUMBER_OF_CHANNELS;
-				int offsetNxNy = offsetNy + (minx * COM_NUMBER_OF_CHANNELS);
-				for (int nx = minx; nx < maxx; nx += QualityStepHelper::getStep()) {
+				int offsetValueNy = ny * inputSizeBuffer->getWidth();
+				int offsetValueNxNy = offsetValueNy + (minx);
+				int offsetColorNxNy = offsetValueNxNy * COM_NUM_CHANNELS_COLOR;
+				for (int nx = minx; nx < maxx; nx += addXStepValue) {
 					if (nx != x || ny != y) {
-						float size = min(inputSizeFloatBuffer[offsetNxNy] * scalar, size_center);
+						float size = min(inputSizeFloatBuffer[offsetValueNxNy] * scalar, size_center);
 						if (size > this->m_threshold) {
 							float dx = nx - x;
 							if (size > fabsf(dx) && size > fabsf(dy)) {
 								float uv[2] = {
-								    (float)(COM_BLUR_BOKEH_PIXELS / 2) + (dx / size) * (float)((COM_BLUR_BOKEH_PIXELS / 2) - 1),
-								    (float)(COM_BLUR_BOKEH_PIXELS / 2) + (dy / size) * (float)((COM_BLUR_BOKEH_PIXELS / 2) - 1)};
-								inputBokehBuffer->readNoCheck(bokeh, uv[0], uv[1]);
-								madd_v4_v4v4(color_accum, bokeh, &inputProgramFloatBuffer[offsetNxNy]);
+									(float)(COM_BLUR_BOKEH_PIXELS / 2) + (dx / size) * (float)((COM_BLUR_BOKEH_PIXELS / 2) - 1),
+									(float)(COM_BLUR_BOKEH_PIXELS / 2) + (dy / size) * (float)((COM_BLUR_BOKEH_PIXELS / 2) - 1)};
+								inputBokehBuffer->read(bokeh, uv[0], uv[1]);
+								madd_v4_v4v4(color_accum, bokeh, &inputProgramFloatBuffer[offsetColorNxNy]);
 								add_v4_v4(multiplier_accum, bokeh);
 							}
 						}
 					}
-					offsetNxNy += addXStep;
-				}
+					offsetColorNxNy += addXStepColor;
+					offsetValueNxNy += addXStepValue;				}
 			}
 		}