5 files changed, 67 insertions, 3 deletions

diff --git a/intern/cycles/blender/addon/properties.py b/intern/cycles/blender/addon/properties.py
index 0a3cffd5071..46a49f52de0 100644
--- a/intern/cycles/blender/addon/properties.py
+++ b/intern/cycles/blender/addon/properties.py
@@ -155,6 +155,10 @@ class CyclesWorldSettings(bpy.types.PropertyGroup):
     @classmethod
     def register(cls):
         bpy.types.World.cycles = PointerProperty(type=cls, name="Cycles World Settings", description="Cycles world settings")
+        cls.sample_as_light = BoolProperty(name="Sample as Lamp", description="Use direct light sampling for the environment, enabling for non-solid colors is recommended",
+            default=False)
+        cls.sample_map_resolution = IntProperty(name="Map Resolution", description="Importance map size is resolution x resolution; higher values potentially produce less noise, at the cost of memory and speed",
+            default=256, min=4, max=8096)
 
     @classmethod
     def unregister(cls):
diff --git a/intern/cycles/blender/addon/ui.py b/intern/cycles/blender/addon/ui.py
index 70f38fa7e8c..67ff79a2037 100644
--- a/intern/cycles/blender/addon/ui.py
+++ b/intern/cycles/blender/addon/ui.py
@@ -453,10 +453,38 @@ class CyclesWorld_PT_surface(CyclesButtonsPanel, Panel):
         layout = self.layout
 
         world = context.world
+
         if not panel_node_draw(layout, world, 'OUTPUT_WORLD', 'Surface'):
             layout.prop(world, "horizon_color", text="Color")
 
 
+class CyclesWorld_PT_settings(CyclesButtonsPanel, Panel):
+    bl_label = "Settings"
+    bl_context = "world"
+    bl_options = {'DEFAULT_CLOSED'}
+
+    @classmethod
+    def poll(cls, context):
+        return context.world and CyclesButtonsPanel.poll(context)
+
+    def draw(self, context):
+        layout = self.layout
+
+        world = context.world
+        cworld = world.cycles
+
+        split = layout.split()
+        col = split.column()
+
+        col.prop(cworld, "sample_as_light")
+        row = col.row()
+        row.active = cworld.sample_as_light
+        row.prop(cworld, "sample_map_resolution")
+
+        col = split.column()
+        col.label()
+
+
 class CyclesWorld_PT_volume(CyclesButtonsPanel, Panel):
     bl_label = "Volume"
     bl_context = "world"
diff --git a/intern/cycles/blender/blender_object.cpp b/intern/cycles/blender/blender_object.cpp
index 608cb33eadd..bc7868e0192 100644
--- a/intern/cycles/blender/blender_object.cpp
+++ b/intern/cycles/blender/blender_object.cpp
@@ -16,10 +16,13 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
+#include "graph.h"
 #include "light.h"
 #include "mesh.h"
 #include "object.h"
 #include "scene.h"
+#include "nodes.h"
+#include "shader.h"
 
 #include "blender_sync.h"
 #include "blender_util.h"
@@ -152,6 +155,35 @@ void BlenderSync::sync_light(BL::Object b_parent, int b_index, BL::Object b_ob,
 	light->tag_update(scene);
 }
 
+void BlenderSync::sync_background_light()
+{
+	BL::World b_world = b_scene.world();
+
+	PointerRNA cworld = RNA_pointer_get(&b_world.ptr, "cycles");
+	bool sample_as_light = get_boolean(cworld, "sample_as_light");
+
+	if(sample_as_light) {
+		/* test if we need to sync */
+		Light *light;
+		ObjectKey key(b_world, 0, b_world);
+
+		if(light_map.sync(&light, b_world, b_world, key) ||
+		   world_recalc ||
+		   b_world.ptr.data != world_map)
+		{
+			light->type = LIGHT_BACKGROUND;
+			light->map_resolution  = get_int(cworld, "sample_map_resolution");
+			light->shader = scene->default_background;
+
+			light->tag_update(scene);
+			light_map.set_recalc(b_world);
+		}
+	}
+
+	world_map = b_world.ptr.data;
+	world_recalc = false;
+}
+
 /* Object */
 
 void BlenderSync::sync_object(BL::Object b_parent, int b_index, BL::Object b_ob, Transform& tfm, uint layer_flag)
@@ -263,6 +295,8 @@ void BlenderSync::sync_objects(BL::SpaceView3D b_v3d)
 		}
 	}
 
+	sync_background_light();
+
 	/* handle removed data and modified pointers */
 	if(light_map.post_sync())
 		scene->light_manager->tag_update(scene);
diff --git a/intern/cycles/blender/blender_shader.cpp b/intern/cycles/blender/blender_shader.cpp
index f5ffc321476..1ce134f3094 100644
--- a/intern/cycles/blender/blender_shader.cpp
+++ b/intern/cycles/blender/blender_shader.cpp
@@ -700,9 +700,6 @@ void BlenderSync::sync_world()
 
 	if(background->modified(prevbackground))
 		background->tag_update(scene);
-
-	world_map = b_world.ptr.data;
-	world_recalc = false;
 }
 
 /* Sync Lamps */
diff --git a/intern/cycles/blender/blender_sync.h b/intern/cycles/blender/blender_sync.h
index 7b65376bd84..5e76a0a0b1e 100644
--- a/intern/cycles/blender/blender_sync.h
+++ b/intern/cycles/blender/blender_sync.h
@@ -80,6 +80,7 @@ private:
 	Mesh *sync_mesh(BL::Object b_ob, bool object_updated);
 	void sync_object(BL::Object b_parent, int b_index, BL::Object b_object, Transform& tfm, uint layer_flag);
 	void sync_light(BL::Object b_parent, int b_index, BL::Object b_ob, Transform& tfm);
+	void sync_background_light();
 
 	/* util */
 	void find_shader(BL::ID id, vector<uint>& used_shaders, int default_shader);