fix some of the issues with camera motion blur (LuxCoreRender#16)

doc/luxcore_api_tips.md

@@ -1,6 +1,6 @@
 When one property of a key is set, all other (previously defined) properties of the key will be deleted.
 Example:
-Let"s say we have set the following properties:
+Let's say we have set the following properties:
 ```
 props.Set(pyluxcore.Property("scene.materials.test.type", "matte"))
 props.Set(pyluxcore.Property("scene.materials.test.kd", [0.7, 0.7, 0.7]))

export/__init__.py

@@ -203,6 +203,8 @@ def create_session(self, engine, scene, context=None):
 
             if enabled and blur_settings.shutter > 0:
                 motion_blur_props = motion_blur.convert(context, scene, objs, self.exported_objects)
+                if camera_blur:
+                    motion_blur_props.Set(camera_props)
                 scene_props.Set(motion_blur_props)
 
         # World

export/camera.py

@@ -35,7 +35,9 @@ def convert(scene, context=None):
         _clipping_plane(scene, definitions)
         _motion_blur(scene, definitions, context)
 
-        return utils.create_props(prefix, definitions)
+        p = utils.create_props(prefix, definitions)
+        print(p)
+        return p
     except Exception as error:
         msg = 'Camera: %s' % error
         scene.luxcore.errorlog.add_warning(msg)
@@ -207,21 +209,20 @@ def _motion_blur(scene, definitions, context):
         return
 
     # TODO why does this not work as expected?
-    # definitions["shutteropen"] = -moblur_settings.shutter * 0.5
-    # definitions["shutterclose"] = moblur_settings.shutter * 0.5
+    definitions["shutteropen"] = -moblur_settings.shutter * 0.5
+    definitions["shutterclose"] = moblur_settings.shutter * 0.5
 
     # # Don't export camera blur in viewport render
-    # if moblur_settings.camera_blur and not context and motion_blur.is_camera_moving(context, scene):
-    #     # Make sure lookup is defined - this function should be the last to modify it
-    #     assert "lookat.orig" in definitions
-    #     assert "lookat.target" in definitions
-    #     assert "up" in definitions
-    #     # Reset lookat - it's handled by motion.x.transformation
-    #     # TODO: seems like this is not needed - why?
-    #     definitions["lookat.orig"] = [0, 0, 0]
-    #     definitions["lookat.target"] = [0, 0, -1]
-    #     definitions["up"] = [0, 1, 0]
-    #     # Note: camera motion system is defined in export/motion_blur.py
+    if moblur_settings.camera_blur and not context and motion_blur.is_camera_moving(context, scene):
+        # Make sure lookup is defined - this function should be the last to modify it
+        assert "lookat.orig" in definitions
+        assert "lookat.target" in definitions
+        assert "up" in definitions
+        # Reset lookat - it's handled by motion.x.transformation
+        definitions["lookat.orig"] = [0, 0, 0]
+        definitions["lookat.target"] = [0, 0, -1]
+        definitions["up"] = [0, 1, 0]
+        # Note: camera motion system is defined in export/motion_blur.py
 
 
 def _calc_lookat(cam_matrix):

export/motion_blur.py

@@ -49,6 +49,7 @@ def convert(context, scene, objects, exported_objects):
                 "motion.%d.transformation" % step: transformation,
             }
             props.Set(utils.create_props(prefix, definitions))
+            print(props)
 
     return props
 
@@ -77,11 +78,13 @@ def _get_matrices(context, scene, steps, times, objects=None, exported_objects=N
             _append_object_matrices(objects, exported_objects, matrices, step)
 
         if motion_blur.camera_blur and not context:
-            matrix = scene.camera.matrix_world.copy()
+            matrix = scene.camera.matrix_world.inverted()
+
             # TODO: This is so stupid. I have no idea what I'm doing
-            rotate = Matrix.Rotation(math.radians(180), 4, "X")
-            scale = Matrix.Scale(-1, 4, (0, 1, 0))
-            matrix = matrix * rotate * scale
+            # rotate = Matrix.Rotation(math.radians(180), 4, "X")
+            # scale = Matrix.Scale(-1, 4, (0, 1, 0))
+            # matrix = matrix * rotate * scale
+
             prefix = "scene.camera."
             _append_matrix(matrices, prefix, matrix, step)
             print("appended camera matrix")