Cycles: Make hair, object and motion blur selective compiled into OpenCL

This features are now based on the scene settings, so scenes without those features
used are rendered even faster.

This gives about 30% speedup on the AMD A10 APU here, but at the same time it does
not mean such an improvement will happen on all the hardware. That being said, the
Tonga device here seems to have no measurable difference.

In any case it seems handy to have for the future, when we'll want to support SSS
in the kernel or to port selective compilation/split kernel to CUDA devices.

1 files changed, 19 insertions, 0 deletions

diff --git a/intern/cycles/render/session.cpp b/intern/cycles/render/session.cpp
index a9a03e54cf7..975fa5a76d1 100644
--- a/intern/cycles/render/session.cpp
+++ b/intern/cycles/render/session.cpp
@@ -22,6 +22,8 @@
 #include "device.h"
 #include "graph.h"
 #include "integrator.h"
+#include "mesh.h"
+#include "object.h"
 #include "scene.h"
 #include "session.h"
 #include "bake.h"
@@ -604,6 +606,7 @@ void Session::run_cpu()
 
 DeviceRequestedFeatures Session::get_requested_device_features()
 {
+	/* TODO(sergey): Consider moving this to the Scene level. */
 	DeviceRequestedFeatures requested_features;
 	requested_features.experimental = params.experimental;
 	if(!params.background) {
@@ -618,6 +621,22 @@ DeviceRequestedFeatures Session::get_requested_device_features()
 		        requested_features.max_nodes_group,
 		        requested_features.nodes_features);
 	}
+
+	/* This features are not being tweaked as often as shaders,
+	 * so could be done selective magic for the viewport as well.
+	 */
+	requested_features.use_hair = false;
+	requested_features.use_object_motion = false;
+	requested_features.use_camera_motion = scene->camera->use_motion;
+	foreach(Object *object, scene->objects) {
+		Mesh *mesh = object->mesh;
+		if(mesh->curves.size() > 0) {
+			requested_features.use_hair = true;
+		}
+		requested_features.use_object_motion |= object->use_motion | mesh->use_motion_blur;
+		requested_features.use_camera_motion |= mesh->use_motion_blur;
+	}
+
 	return requested_features;
 }