New compositor node "Sun Beams"

This allows adding a "fake" sun beam effect, simulating crepuscular rays
from light being scattered in a medium like the atmosphere or deep water.
Such effects can be created also by renderers using volumetric lighting,
but the compositor feature is a lot cheaper and is independent from 3D
rendering. This makes it ideally suited for motion graphics.

The implementation uses am optimized accumulation method for gathering
color values along a line segment. The inner buffer loop uses fixed
offset increments to avoid unnecessary multiplications and avoids
variables by using compile-time specialization (see inline comments
for further details).

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_node_types.h b/source/blender/makesdna/DNA_node_types.h
index b13353609c6..e0d25e763d4 100644
--- a/source/blender/makesdna/DNA_node_types.h
+++ b/source/blender/makesdna/DNA_node_types.h
@@ -852,6 +852,12 @@ typedef struct NodeShaderUVMap {
 	char uv_map[64];
 } NodeShaderUVMap;
 
+typedef struct NodeSunBeams {
+	float source[2];
+
+	float ray_length;
+} NodeSunBeams;
+
 /* script node mode */
 #define NODE_SCRIPT_INTERNAL		0
 #define NODE_SCRIPT_EXTERNAL		1