Cycles: pointcloud rendering

This add support for rendering of the point cloud object in Blender, as a native
geometry type in Cycles that is more memory and time efficient than instancing
sphere meshes. This can be useful for rendering sand, water splashes, particles,
motion graphics, etc.

Points are currently always rendered as spheres, with backface culling. More
shapes are likely to be added later, but this is the most important one and can
be customized with shaders.

For CPU rendering the Embree primitive is used, for GPU there is our own
intersection code. Motion blur is suppored. Volumes inside points are not
currently supported.

Implemented with help from:
* Kévin Dietrich: Alembic procedural integration
* Patrick Mourse: OptiX integration
* Josh Whelchel: update for cycles-x changes

Ref T92573

Differential Revision: https://developer.blender.org/D9887

1 files changed, 22 insertions, 0 deletions

diff --git a/intern/cycles/scene/scene.cpp b/intern/cycles/scene/scene.cpp
index 452b5215836..1963ebbbb19 100644
--- a/intern/cycles/scene/scene.cpp
+++ b/intern/cycles/scene/scene.cpp
@@ -30,6 +30,7 @@
 #include "scene/object.h"
 #include "scene/osl.h"
 #include "scene/particles.h"
+#include "scene/pointcloud.h"
 #include "scene/procedural.h"
 #include "scene/scene.h"
 #include "scene/shader.h"
@@ -64,6 +65,8 @@ DeviceScene::DeviceScene(Device *device)
       curve_keys(device, "__curve_keys", MEM_GLOBAL),
       curve_segments(device, "__curve_segments", MEM_GLOBAL),
       patches(device, "__patches", MEM_GLOBAL),
+      points(device, "__points", MEM_GLOBAL),
+      points_shader(device, "__points_shader", MEM_GLOBAL),
       objects(device, "__objects", MEM_GLOBAL),
       object_motion_pass(device, "__object_motion_pass", MEM_GLOBAL),
       object_motion(device, "__object_motion", MEM_GLOBAL),
@@ -523,6 +526,9 @@ void Scene::update_kernel_features()
     else if (geom->is_hair()) {
       kernel_features |= KERNEL_FEATURE_HAIR;
     }
+    else if (geom->is_pointcloud()) {
+      kernel_features |= KERNEL_FEATURE_POINTCLOUD;
+    }
   }
 
   if (bake_manager->get_baking()) {
@@ -575,6 +581,7 @@ static void log_kernel_features(const uint features)
   VLOG(2) << "Use Path Tracing " << string_from_bool(features & KERNEL_FEATURE_PATH_TRACING)
           << "\n";
   VLOG(2) << "Use Hair " << string_from_bool(features & KERNEL_FEATURE_HAIR) << "\n";
+  VLOG(2) << "Use Pointclouds " << string_from_bool(features & KERNEL_FEATURE_POINTCLOUD) << "\n";
   VLOG(2) << "Use Object Motion " << string_from_bool(features & KERNEL_FEATURE_OBJECT_MOTION)
           << "\n";
   VLOG(2) << "Use Camera Motion " << string_from_bool(features & KERNEL_FEATURE_CAMERA_MOTION)
@@ -757,6 +764,15 @@ template<> Volume *Scene::create_node<Volume>()
   return node;
 }
 
+template<> PointCloud *Scene::create_node<PointCloud>()
+{
+  PointCloud *node = new PointCloud();
+  node->set_owner(this);
+  geometry.push_back(node);
+  geometry_manager->tag_update(this, GeometryManager::POINT_ADDED);
+  return node;
+}
+
 template<> Object *Scene::create_node<Object>()
 {
   Object *node = new Object();
@@ -844,6 +860,12 @@ template<> void Scene::delete_node_impl(Volume *node)
   geometry_manager->tag_update(this, GeometryManager::MESH_REMOVED);
 }
 
+template<> void Scene::delete_node_impl(PointCloud *node)
+{
+  delete_node_from_array(geometry, static_cast<Geometry *>(node));
+  geometry_manager->tag_update(this, GeometryManager::POINT_REMOVED);
+}
+
 template<> void Scene::delete_node_impl(Geometry *node)
 {
   uint flag;