Outliner: Allow select on row icons

Allow selection of subtree elements on a collapsed element's
row. Because subtree elements are aggregated by type, a select on
an icon that represents multiple subtree elements will invoke a
popup menu to select the specific subtree element.

Also draws highlights on cursor hover over a row icon.

Any child elements that are linked to multiple collections will
only be listed in the popup one time, and selection from the
popup will select the first instance in the subtree.

1 files changed, 14 insertions, 3 deletions

diff --git a/source/blender/editors/space_outliner/outliner_draw.c b/source/blender/editors/space_outliner/outliner_draw.c
index a2fe131198d..a3b1c03a1b8 100644
--- a/source/blender/editors/space_outliner/outliner_draw.c
+++ b/source/blender/editors/space_outliner/outliner_draw.c
@@ -2590,7 +2590,11 @@ static void tselem_draw_icon(uiBlock *block,
     return;
   }
 
+  /* Icon is covered by restrict buttons */
   if (!is_clickable || x >= xmax) {
+    /* Reduce alpha to match icon buttons */
+    alpha *= 0.8f;
+
     /* placement of icons, copied from interface_widgets.c */
     float aspect = (0.8f * UI_UNIT_Y) / ICON_DEFAULT_HEIGHT;
     x += 2.0f * aspect;
@@ -2698,7 +2702,6 @@ static void outliner_draw_iconrow_doit(uiBlock *block,
     float ufac = UI_UNIT_X / 20.0f;
     float icon_color[4], icon_border[4];
     outliner_icon_background_colors(icon_color, icon_border);
-    icon_color[3] *= alpha_fac;
     if (active == OL_DRAWSEL_ACTIVE) {
       UI_GetThemeColor4fv(TH_EDITED_OBJECT, icon_color);
       icon_border[3] = 0.3f;
@@ -2723,6 +2726,9 @@ static void outliner_draw_iconrow_doit(uiBlock *block,
     GPU_blend(true); /* Roundbox disables. */
   }
 
+  if (tselem->flag & TSE_HIGHLIGHTED) {
+    alpha_fac += 0.5;
+  }
   tselem_draw_icon(block, xmax, (float)*offsx, (float)ys, tselem, te, alpha_fac, false);
   te->xs = *offsx;
   te->ys = ys;
@@ -2730,7 +2736,12 @@ static void outliner_draw_iconrow_doit(uiBlock *block,
 
   if (num_elements > 1) {
     outliner_draw_iconrow_number(fstyle, *offsx, ys, num_elements);
+    te->flag |= TE_ICONROW_MERGED;
   }
+  else {
+    te->flag |= TE_ICONROW;
+  }
+
   (*offsx) += UI_UNIT_X;
 }
 
@@ -2740,7 +2751,7 @@ static void outliner_draw_iconrow_doit(uiBlock *block,
  * We use a continuum of indices until we get to the object data-blocks
  * and we then make room for the object types.
  */
-static int tree_element_id_type_to_index(TreeElement *te)
+int tree_element_id_type_to_index(TreeElement *te)
 {
   TreeStoreElem *tselem = TREESTORE(te);
 
@@ -2870,7 +2881,7 @@ static void outliner_set_coord_tree_element(TreeElement *te, int startx, int sta
   TreeElement *ten;
 
   /* closed items may be displayed in row of parent, don't change their coordinate! */
-  if ((te->flag & TE_ICONROW) == 0) {
+  if ((te->flag & TE_ICONROW) == 0 && (te->flag & TE_ICONROW_MERGED) == 0) {
     /* store coord and continue, we need coordinates for elements outside view too */
     te->xs = startx;
     te->ys = starty;