Cycles: Reduce verbosity of logging

Mainly makes logging less verbose when doing progressive sampling in viewport.

Such kind of verbosity is not really possible to be filtered out with `grep`
so let's reshuffle few lines of code.

intern/cycles/render/light.cpp

@@ -771,11 +771,11 @@ void LightManager::device_update_points(Device *device,
 
 void LightManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
-	VLOG(1) << "Total " << scene->lights.size() << " lights.";
-
 	if(!need_update)
 		return;
 
+	VLOG(1) << "Total " << scene->lights.size() << " lights.";
+
 	device_free(device, dscene);
 
 	use_light_visibility = false;

intern/cycles/render/mesh.cpp

@@ -1232,11 +1232,11 @@ void MeshManager::device_update_displacement_images(Device *device,
 
 void MeshManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
-	VLOG(1) << "Total " << scene->meshes.size() << " meshes.";
-
 	if(!need_update)
 		return;
 
+	VLOG(1) << "Total " << scene->meshes.size() << " meshes.";
+
 	/* update normals */
 	foreach(Mesh *mesh, scene->meshes) {
 		foreach(uint shader, mesh->used_shaders) {

intern/cycles/render/object.cpp

@@ -480,11 +480,11 @@ void ObjectManager::device_update_transforms(Device *device,
 
 void ObjectManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
-	VLOG(1) << "Total " << scene->objects.size() << " objects.";
-
 	if(!need_update)
 		return;
-	
+
+	VLOG(1) << "Total " << scene->objects.size() << " objects.";
+
 	device_free(device, dscene);
 
 	if(scene->objects.size() == 0)

intern/cycles/render/osl.cpp

@@ -75,11 +75,11 @@ void OSLShaderManager::reset(Scene * /*scene*/)
 
 void OSLShaderManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
-	VLOG(1) << "Total " << scene->shaders.size() << " shaders.";
-
 	if(!need_update)
 		return;
 
+	VLOG(1) << "Total " << scene->shaders.size() << " shaders.";
+
 	device_free(device, dscene, scene);
 
 	/* determine which shaders are in use */

intern/cycles/render/particles.cpp

@@ -93,12 +93,12 @@ void ParticleSystemManager::device_update_particles(Device *device, DeviceScene
 
 void ParticleSystemManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
+	if(!need_update)
+		return;
+
 	VLOG(1) << "Total " << scene->particle_systems.size()
 	        << " particle systems.";
 
-	if(!need_update)
-		return;
-	
 	device_free(device, dscene);
 
 	progress.set_status("Updating Particle Systems", "Copying Particles to device");

intern/cycles/render/scene.cpp

@@ -135,7 +135,9 @@ void Scene::device_update(Device *device_, Progress& progress)
 {
 	if(!device)
 		device = device_;
-	
+
+	bool print_stats = need_data_update();
+
 	/* The order of updates is important, because there's dependencies between
 	 * the different managers, using data computed by previous managers.
 	 *
@@ -239,9 +241,11 @@ void Scene::device_update(Device *device_, Progress& progress)
 		device->const_copy_to("__data", &dscene.data, sizeof(dscene.data));
 	}
 
-	VLOG(1) << "System memory statistics after full device sync:\n"
-	        << "  Usage: " << util_guarded_get_mem_used() << "\n"
-	        << "  Peak: " << util_guarded_get_mem_peak();
+	if(print_stats) {
+		VLOG(1) << "System memory statistics after full device sync:\n"
+		        << "  Usage: " << util_guarded_get_mem_used() << "\n"
+		        << "  Peak: " << util_guarded_get_mem_peak();
+	}
 }
 
 Scene::MotionType Scene::need_motion(bool advanced_shading)
@@ -278,11 +282,10 @@ bool Scene::need_update()
 	return (need_reset() || film->need_update);
 }
 
-bool Scene::need_reset()
+bool Scene::need_data_update()
 {
 	return (background->need_update
 		|| image_manager->need_update
-		|| camera->need_update
 		|| object_manager->need_update
 		|| mesh_manager->need_update
 		|| light_manager->need_update
@@ -295,6 +298,11 @@ bool Scene::need_reset()
 		|| film->need_update);
 }
 
+bool Scene::need_reset()
+{
+	return need_data_update() || camera->need_update;
+}
+
 void Scene::reset()
 {
 	shader_manager->reset(this);

intern/cycles/render/scene.h

@@ -213,6 +213,11 @@ public:
 	void device_free();
 
 protected:
+	/* Check if some heavy data worth logging was updated.
+	 * Mainly used to suppress extra annoying logging.
+	 */
+	bool need_data_update();
+
 	void free_memory(bool final);
 };
 

intern/cycles/render/svm.cpp

@@ -46,11 +46,11 @@ void SVMShaderManager::reset(Scene * /*scene*/)
 
 void SVMShaderManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
 {
-	VLOG(1) << "Total " << scene->shaders.size() << " shaders.";
-
 	if(!need_update)
 		return;
 
+	VLOG(1) << "Total " << scene->shaders.size() << " shaders.";
+
 	/* test if we need to update */
 	device_free(device, dscene, scene);
 

intern/cycles/render/tables.cpp

@@ -37,11 +37,11 @@ LookupTables::~LookupTables()
 
 void LookupTables::device_update(Device *device, DeviceScene *dscene)
 {
-	VLOG(1) << "Total " << lookup_tables.size() << " lookup tables.";
-
 	if(!need_update)
 		return;
 
+	VLOG(1) << "Total " << lookup_tables.size() << " lookup tables.";
+
 	device->tex_free(dscene->lookup_table);
 
 	if(lookup_tables.size() > 0)