Cycles: optimize 3D viewport rendering with camera passepartout

If the area outside the camera is fully opaque, don't render it.

Contributed by Kdaf.

Differential Revision: https://developer.blender.org/D11182

3 files changed, 25 insertions, 18 deletions

diff --git a/intern/cycles/blender/blender_camera.cpp b/intern/cycles/blender/blender_camera.cpp
index b31841801d8..6954c5c2f26 100644
--- a/intern/cycles/blender/blender_camera.cpp
+++ b/intern/cycles/blender/blender_camera.cpp
@@ -83,6 +83,8 @@ struct BlenderCamera {
   BoundBox2D pano_viewplane;
   BoundBox2D viewport_camera_border;
 
+  float passepartout_alpha;
+
   Transform matrix;
 
   float offscreen_dicing_scale;
@@ -125,6 +127,7 @@ static void blender_camera_init(BlenderCamera *bcam, BL::RenderSettings &b_rende
   bcam->pano_viewplane.top = 1.0f;
   bcam->viewport_camera_border.right = 1.0f;
   bcam->viewport_camera_border.top = 1.0f;
+  bcam->passepartout_alpha = 0.5f;
   bcam->offscreen_dicing_scale = 1.0f;
   bcam->matrix = transform_identity();
 
@@ -212,6 +215,8 @@ static void blender_camera_from_object(BlenderCamera *bcam,
 
     bcam->lens = b_camera.lens();
 
+    bcam->passepartout_alpha = b_camera.show_passepartout() ? b_camera.passepartout_alpha() : 0.0f;
+
     if (b_camera.dof().use_dof()) {
       /* allow f/stop number to change aperture_size but still
        * give manual control over aperture radius */
@@ -834,15 +839,19 @@ static void blender_camera_border(BlenderCamera *bcam,
                                full_border,
                                &bcam->viewport_camera_border);
 
-  if (!b_render.use_border()) {
+  if (b_render.use_border()) {
+    bcam->border.left = b_render.border_min_x();
+    bcam->border.right = b_render.border_max_x();
+    bcam->border.bottom = b_render.border_min_y();
+    bcam->border.top = b_render.border_max_y();
+  }
+  else if (bcam->passepartout_alpha == 1.0f) {
+    bcam->border = full_border;
+  }
+  else {
     return;
   }
 
-  bcam->border.left = b_render.border_min_x();
-  bcam->border.right = b_render.border_max_x();
-  bcam->border.bottom = b_render.border_min_y();
-  bcam->border.top = b_render.border_max_y();
-
   /* Determine viewport subset matching camera border. */
   blender_camera_border_subset(b_engine,
                                b_render,
@@ -885,8 +894,7 @@ void BlenderSync::sync_view(BL::SpaceView3D &b_v3d,
   }
 }
 
-BufferParams BlenderSync::get_buffer_params(BL::RenderSettings &b_render,
-                                            BL::SpaceView3D &b_v3d,
+BufferParams BlenderSync::get_buffer_params(BL::SpaceView3D &b_v3d,
                                             BL::RegionView3D &b_rv3d,
                                             Camera *cam,
                                             int width,
@@ -902,7 +910,8 @@ BufferParams BlenderSync::get_buffer_params(BL::RenderSettings &b_render,
   if (b_v3d && b_rv3d && b_rv3d.view_perspective() != BL::RegionView3D::view_perspective_CAMERA)
     use_border = b_v3d.use_render_border();
   else
-    use_border = b_render.use_border();
+    /* the camera can always have a passepartout */
+    use_border = true;
 
   if (use_border) {
     /* border render */
diff --git a/intern/cycles/blender/blender_session.cpp b/intern/cycles/blender/blender_session.cpp
index 89854f6a0e5..29de886e4ff 100644
--- a/intern/cycles/blender/blender_session.cpp
+++ b/intern/cycles/blender/blender_session.cpp
@@ -155,7 +155,7 @@ void BlenderSession::create_session()
 
   /* set buffer parameters */
   BufferParams buffer_params = BlenderSync::get_buffer_params(
-      b_render, b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
+      b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
   session->reset(buffer_params, session_params.samples);
 
   b_engine.use_highlight_tiles(session_params.progressive_refine == false);
@@ -242,8 +242,7 @@ void BlenderSession::reset_session(BL::BlendData &b_data, BL::Depsgraph &b_depsg
 
   BL::SpaceView3D b_null_space_view3d(PointerRNA_NULL);
   BL::RegionView3D b_null_region_view3d(PointerRNA_NULL);
-  BufferParams buffer_params = BlenderSync::get_buffer_params(b_render,
-                                                              b_null_space_view3d,
+  BufferParams buffer_params = BlenderSync::get_buffer_params(b_null_space_view3d,
                                                               b_null_region_view3d,
                                                               scene->camera,
                                                               width,
@@ -486,7 +485,7 @@ void BlenderSession::render(BL::Depsgraph &b_depsgraph_)
   SessionParams session_params = BlenderSync::get_session_params(
       b_engine, b_userpref, b_scene, background, b_view_layer);
   BufferParams buffer_params = BlenderSync::get_buffer_params(
-      b_render, b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
+      b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
 
   /* temporary render result to find needed passes and views */
   BL::RenderResult b_rr = begin_render_result(
@@ -810,7 +809,7 @@ void BlenderSession::synchronize(BL::Depsgraph &b_depsgraph_)
 
   /* get buffer parameters */
   BufferParams buffer_params = BlenderSync::get_buffer_params(
-      b_render, b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
+      b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
 
   if (!buffer_params.denoising_data_pass) {
     session_params.denoising.use = false;
@@ -889,7 +888,7 @@ bool BlenderSession::draw(int w, int h)
       SessionParams session_params = BlenderSync::get_session_params(
           b_engine, b_userpref, b_scene, background);
       BufferParams buffer_params = BlenderSync::get_buffer_params(
-          b_render, b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
+          b_v3d, b_rv3d, scene->camera, width, height, session_params.denoising.use);
       bool session_pause = BlenderSync::get_session_pause(b_scene, background);
 
       if (session_pause == false) {
@@ -907,7 +906,7 @@ bool BlenderSession::draw(int w, int h)
 
   /* draw */
   BufferParams buffer_params = BlenderSync::get_buffer_params(
-      b_render, b_v3d, b_rv3d, scene->camera, width, height, session->params.denoising.use);
+      b_v3d, b_rv3d, scene->camera, width, height, session->params.denoising.use);
   DeviceDrawParams draw_params;
 
   if (session->params.display_buffer_linear) {
diff --git a/intern/cycles/blender/blender_sync.h b/intern/cycles/blender/blender_sync.h
index 8cd65f13f70..1c98e529190 100644
--- a/intern/cycles/blender/blender_sync.h
+++ b/intern/cycles/blender/blender_sync.h
@@ -104,8 +104,7 @@ class BlenderSync {
       bool background,
       BL::ViewLayer b_view_layer = BL::ViewLayer(PointerRNA_NULL));
   static bool get_session_pause(BL::Scene &b_scene, bool background);
-  static BufferParams get_buffer_params(BL::RenderSettings &b_render,
-                                        BL::SpaceView3D &b_v3d,
+  static BufferParams get_buffer_params(BL::SpaceView3D &b_v3d,
                                         BL::RegionView3D &b_rv3d,
                                         Camera *cam,
                                         int width,