[Bf-blender-cvs] [fdb16b162e0] soc-2022-many-lights-sampling: implement initial bounding computations for point lights

[Jebbly]

Commit: fdb16b162e0437d9ae4db8920077b4c6b73b89f9
Author: Jebbly
Date:   Wed Jun 8 00:49:47 2022 -0400
Branches: soc-2022-many-lights-sampling
https://developer.blender.org/rBfdb16b162e0437d9ae4db8920077b4c6b73b89f9

implement initial bounding computations for point lights

===================================================================

M	intern/cycles/scene/light_tree.cpp
M	intern/cycles/scene/light_tree.h

===================================================================

diff --git a/intern/cycles/scene/light_tree.cpp b/intern/cycles/scene/light_tree.cpp
index 6340440b81b..dc713c229f9 100644
--- a/intern/cycles/scene/light_tree.cpp
+++ b/intern/cycles/scene/light_tree.cpp
@@ -53,6 +53,37 @@ OrientationBounds merge(const OrientationBounds& cone_a,
   }
 }
 
+/* to-do: right now, this is assuming that the primitive is a point light.
+/* The plan is to progressively add support for more primitives. 
+/* Some of the logic is different from the past GSoC work, so 
+/* will have to see which logic is more correct. */
+BoundBox LightTreePrimitive::calculate_bbox(Scene *scene) const
+{
+  BoundBox bbox = BoundBox::empty;
+  Light *lamp = scene->lights[lamp_id];
+  /* A point light should occupy no space, but the bounding box
+  /* should at least contain the position of the point. */
+  bbox.grow(lamp->get_co());
+  return bbox;
+}
+
+OrientationBounds LightTreePrimitive::calculate_bcone(Scene *scene) const
+{
+  OrientationBounds bcone;
+  Light *lamp = scene->lights[lamp_id];
+  bcone.axis = lamp->get_dir() / len(lamp->get_dir());
+  bcone.theta_o = M_PI_F;
+  bcone.theta_e = M_PI_2_F;
+  return bcone;
+}
+
+float LightTreePrimitive::calculate_energy(Scene *scene) const
+{
+  Light *lamp = scene->lights[lamp_id];
+  /* Past GSoC work also divides this by pi, but will need to test which is more accurate. */
+  return scene->shader_manager->linear_rgb_to_gray(lamp->get_strength());
+}
+
 void LightTreeBuildNode::init_leaf(
     uint offset, uint n, const BoundBox &b, const OrientationBounds &c, float e, float e_var)
 {
diff --git a/intern/cycles/scene/light_tree.h b/intern/cycles/scene/light_tree.h
index 8c68eefe9af..25e3bfba318 100644
--- a/intern/cycles/scene/light_tree.h
+++ b/intern/cycles/scene/light_tree.h
@@ -4,6 +4,7 @@
 #ifndef __LIGHT_TREE_H__
 #define __LIGHT_TREE_H__
 
+#include "scene/light.h"
 #include "scene/scene.h"
 
 #include "util/boundbox.h"