Fix T73931: Stereo Viewport Color Management

Stereoscopic viewport didn't support Color Manangement due recent
changes in the color management pipeline. In order to solve the issue we
will migrate the strereo rendering into the GPUViewport. This will share
some textures and reduce required GPU memory.

Reviewed By: fclem, dfelinto

Differential Revision: https://developer.blender.org/D6922

1 files changed, 32 insertions, 41 deletions

diff --git a/source/blender/windowmanager/intern/wm_draw.c b/source/blender/windowmanager/intern/wm_draw.c
index 5289b747f05..38cd667c422 100644
--- a/source/blender/windowmanager/intern/wm_draw.c
+++ b/source/blender/windowmanager/intern/wm_draw.c
@@ -235,7 +235,7 @@ static void wm_region_test_render_do_draw(const Scene *scene,
   if (sa->spacetype == SPACE_VIEW3D && region->regiontype == RGN_TYPE_WINDOW) {
     RegionView3D *rv3d = region->regiondata;
     RenderEngine *engine = rv3d->render_engine;
-    GPUViewport *viewport = WM_draw_region_get_viewport(region, 0);
+    GPUViewport *viewport = WM_draw_region_get_viewport(region);
 
     if (engine && (engine->flag & RE_ENGINE_DO_DRAW)) {
       View3D *v3d = sa->spacedata.first;
@@ -332,10 +332,8 @@ static void wm_draw_callbacks(wmWindow *win)
 static void wm_draw_region_buffer_free(ARegion *region)
 {
   if (region->draw_buffer) {
-    for (int view = 0; view < 2; view++) {
-      if (region->draw_buffer->viewport[view]) {
-        GPU_viewport_free(region->draw_buffer->viewport[view]);
-      }
+    if (region->draw_buffer->viewport) {
+      GPU_viewport_free(region->draw_buffer->viewport);
     }
     if (region->draw_buffer->offscreen) {
       GPU_offscreen_free(region->draw_buffer->offscreen);
@@ -361,7 +359,6 @@ static void wm_draw_offscreen_texture_parameters(GPUOffScreen *offscreen)
   /* GL_TEXTURE_BASE_LEVEL = 0 by default */
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-
   glBindTexture(GL_TEXTURE_2D, 0);
 }
 
@@ -387,8 +384,8 @@ static void wm_draw_region_buffer_create(ARegion *region, bool stereo, bool use_
       /* Allocate viewport which includes an offscreen buffer with depth
        * multisample, etc. */
       region->draw_buffer = MEM_callocN(sizeof(wmDrawBuffer), "wmDrawBuffer");
-      region->draw_buffer->viewport[0] = GPU_viewport_create();
-      region->draw_buffer->viewport[1] = (stereo) ? GPU_viewport_create() : NULL;
+      region->draw_buffer->viewport = stereo ? GPU_viewport_stereo_create() :
+                                               GPU_viewport_create();
     }
     else {
       /* Allocate offscreen buffer if it does not exist. This one has no
@@ -417,8 +414,8 @@ static void wm_draw_region_bind(ARegion *region, int view)
     return;
   }
 
-  if (region->draw_buffer->viewport[view]) {
-    GPU_viewport_bind(region->draw_buffer->viewport[view], &region->winrct);
+  if (region->draw_buffer->viewport) {
+    GPU_viewport_bind(region->draw_buffer->viewport, view, &region->winrct);
   }
   else {
     GPU_offscreen_bind(region->draw_buffer->offscreen, false);
@@ -432,7 +429,7 @@ static void wm_draw_region_bind(ARegion *region, int view)
   region->draw_buffer->bound_view = view;
 }
 
-static void wm_draw_region_unbind(ARegion *region, int view)
+static void wm_draw_region_unbind(ARegion *region)
 {
   if (!region->draw_buffer) {
     return;
@@ -440,8 +437,8 @@ static void wm_draw_region_unbind(ARegion *region, int view)
 
   region->draw_buffer->bound_view = -1;
 
-  if (region->draw_buffer->viewport[view]) {
-    GPU_viewport_unbind(region->draw_buffer->viewport[view]);
+  if (region->draw_buffer->viewport) {
+    GPU_viewport_unbind(region->draw_buffer->viewport);
   }
   else {
     glDisable(GL_SCISSOR_TEST);
@@ -460,14 +457,14 @@ static void wm_draw_region_blit(ARegion *region, int view)
     view = 0;
   }
   else if (view > 0) {
-    if (region->draw_buffer->viewport[view] == NULL) {
+    if (region->draw_buffer->viewport == NULL) {
       /* Region does not need stereo or failed to allocate stereo buffers. */
       view = 0;
     }
   }
 
-  if (region->draw_buffer->viewport[view]) {
-    GPU_viewport_draw_to_screen(region->draw_buffer->viewport[view], &region->winrct);
+  if (region->draw_buffer->viewport) {
+    GPU_viewport_draw_to_screen(region->draw_buffer->viewport, view, &region->winrct);
   }
   else {
     GPU_offscreen_draw_to_screen(
@@ -481,8 +478,9 @@ GPUTexture *wm_draw_region_texture(ARegion *region, int view)
     return NULL;
   }
 
-  if (region->draw_buffer->viewport[view]) {
-    return GPU_viewport_color_texture(region->draw_buffer->viewport[view]);
+  GPUViewport *viewport = region->draw_buffer->viewport;
+  if (viewport) {
+    return GPU_viewport_color_texture(viewport, view);
   }
   else {
     return GPU_offscreen_color_texture(region->draw_buffer->offscreen);
@@ -573,13 +571,14 @@ void wm_draw_region_blend(ARegion *region, int view, bool blend)
   }
 }
 
-GPUViewport *WM_draw_region_get_viewport(ARegion *region, int view)
+GPUViewport *WM_draw_region_get_viewport(ARegion *region)
 {
   if (!region->draw_buffer) {
     return NULL;
   }
 
-  return region->draw_buffer->viewport[view];
+  GPUViewport *viewport = region->draw_buffer->viewport;
+  return viewport;
 }
 
 GPUViewport *WM_draw_region_get_bound_viewport(ARegion *region)
@@ -588,8 +587,8 @@ GPUViewport *WM_draw_region_get_bound_viewport(ARegion *region)
     return NULL;
   }
 
-  int view = region->draw_buffer->bound_view;
-  return region->draw_buffer->viewport[view];
+  GPUViewport *viewport = region->draw_buffer->viewport;
+  return viewport;
 }
 
 static void wm_draw_window_offscreen(bContext *C, wmWindow *win, bool stereo)
@@ -650,14 +649,18 @@ static void wm_draw_window_offscreen(bContext *C, wmWindow *win, bool stereo)
 
             wm_draw_region_bind(region, view);
             ED_region_do_draw(C, region);
-            wm_draw_region_unbind(region, view);
+            wm_draw_region_unbind(region);
+          }
+          if (use_viewport) {
+            GPUViewport *viewport = region->draw_buffer->viewport;
+            GPU_viewport_stereo_composite(viewport, win->stereo3d_format);
           }
         }
         else {
           wm_draw_region_buffer_create(region, false, use_viewport);
           wm_draw_region_bind(region, 0);
           ED_region_do_draw(C, region);
-          wm_draw_region_unbind(region, 0);
+          wm_draw_region_unbind(region);
         }
 
         region->do_draw = false;
@@ -686,7 +689,7 @@ static void wm_draw_window_offscreen(bContext *C, wmWindow *win, bool stereo)
       glClearColor(0, 0, 0, 0);
       glClear(GL_COLOR_BUFFER_BIT);
       ED_region_do_draw(C, region);
-      wm_draw_region_unbind(region, 0);
+      wm_draw_region_unbind(region);
 
       region->do_draw = false;
       CTX_wm_menu_set(C, NULL);
@@ -715,19 +718,8 @@ static void wm_draw_window_onscreen(bContext *C, wmWindow *win, int view)
   {
     for (ARegion *region = sa->regionbase.first; region; region = region->next) {
       if (region->visible && region->overlap == false) {
-        if (view == -1 && region->draw_buffer && region->draw_buffer->stereo) {
-          /* Stereo drawing from textures. */
-          if (win->stereo3d_format->display_mode == S3D_DISPLAY_ANAGLYPH) {
-            wm_stereo3d_draw_anaglyph(win, region);
-          }
-          else {
-            wm_stereo3d_draw_interlace(win, region);
-          }
-        }
-        else {
-          /* Blit from offscreen buffer. */
-          wm_draw_region_blit(region, view);
-        }
+        /* Blit from offscreen buffer. */
+        wm_draw_region_blit(region, view);
       }
     }
   }
@@ -789,7 +781,6 @@ static void wm_draw_window(bContext *C, wmWindow *win)
 {
   bScreen *screen = WM_window_get_active_screen(win);
   bool stereo = WM_stereo3d_enabled(win, false);
-
   /* Draw area regions into their own framebuffer. This way we can redraw
    * the areas that need it, and blit the rest from existing framebuffers. */
   wm_draw_window_offscreen(C, win, stereo);
@@ -1028,7 +1019,7 @@ void wm_draw_region_test(bContext *C, ScrArea *sa, ARegion *region)
   wm_draw_region_buffer_create(region, false, use_viewport);
   wm_draw_region_bind(region, 0);
   ED_region_do_draw(C, region);
-  wm_draw_region_unbind(region, 0);
+  wm_draw_region_unbind(region);
   region->do_draw = false;
 }
 
@@ -1068,7 +1059,7 @@ void WM_draw_region_viewport_bind(ARegion *region)
 
 void WM_draw_region_viewport_unbind(ARegion *region)
 {
-  wm_draw_region_unbind(region, 0);
+  wm_draw_region_unbind(region);
 }
 
 /** \} */