Cycles: Display RenderPass in Viewport

This change allows the user to select a renderpass in the 3d viewport.

Added support for external renderers to extend the `View3DShading` struct.
This way Blender doesn't need to know the features an external render engine wants to support.
Note that the View3DShading is also available in the scene->display.shading; although this is
supported, it does not make sense for render engines to put something here as it is really
scene/workbench related.

Currently cycles assumes that it always needs to calculate the combined pass; it ignores the
`pass_flag` in KernelFilm. We could optimize this but that was not in scope of this change

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D5689

2 files changed, 22 insertions, 0 deletions

diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index bd2580dba74..e9d4af447e0 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -6353,6 +6353,14 @@ static void direct_link_lightcache(FileData *fd, LightCache *cache)
   cache->grid_data = newdataadr(fd, cache->grid_data);
 }
 
+static void direct_link_view3dshading(FileData *fd, View3DShading *shading)
+{
+  if (shading->prop) {
+    shading->prop = newdataadr(fd, shading->prop);
+    IDP_DirectLinkGroup_OrFree(&shading->prop, (fd->flags & FD_FLAGS_SWITCH_ENDIAN), fd);
+  }
+}
+
 /* check for cyclic set-scene,
  * libs can cause this case which is normally prevented, see (T#####) */
 #define USE_SETSCENE_CHECK
@@ -6987,6 +6995,8 @@ static void direct_link_scene(FileData *fd, Scene *sce)
     }
   }
 
+  direct_link_view3dshading(fd, &sce->display.shading);
+
   sce->layer_properties = newdataadr(fd, sce->layer_properties);
   IDP_DirectLinkGroup_OrFree(&sce->layer_properties, (fd->flags & FD_FLAGS_SWITCH_ENDIAN), fd);
 }
@@ -7255,6 +7265,8 @@ static void direct_link_area(FileData *fd, ScrArea *area)
         v3d->fx_settings.ssao = newdataadr(fd, v3d->fx_settings.ssao);
       }
 
+      direct_link_view3dshading(fd, &v3d->shading);
+
       blo_do_versions_view3d_split_250(v3d, &sl->regionbase);
     }
     else if (sl->spacetype == SPACE_GRAPH) {
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index c9c3a96fb32..d698c94dbfb 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -2413,6 +2413,13 @@ static void write_view_settings(WriteData *wd, ColorManagedViewSettings *view_se
   }
 }
 
+static void write_view3dshading(WriteData *wd, View3DShading *shading)
+{
+  if (shading->prop) {
+    IDP_WriteProperty(shading->prop, wd);
+  }
+}
+
 static void write_paint(WriteData *wd, Paint *p)
 {
   if (p->cavity_curve) {
@@ -2684,6 +2691,8 @@ static void write_scene(WriteData *wd, Scene *sce)
     write_lightcache(wd, sce->eevee.light_cache);
   }
 
+  write_view3dshading(wd, &sce->display.shading);
+
   /* Freed on doversion. */
   BLI_assert(sce->layer_properties == NULL);
 }
@@ -2850,6 +2859,7 @@ static void write_area_regions(WriteData *wd, ScrArea *area)
       if (v3d->fx_settings.dof) {
         writestruct(wd, DATA, GPUDOFSettings, 1, v3d->fx_settings.dof);
       }
+      write_view3dshading(wd, &v3d->shading);
     }
     else if (sl->spacetype == SPACE_GRAPH) {
       SpaceGraph *sipo = (SpaceGraph *)sl;