Add custom indexes for edges and faces (Viewer Index node) (#4595)

* add custom indexes for edges and faces

* fix problem not displaying custom text when node.draw_bface property was disabled

* update documentation

* fix list doc element

docs/nodes/viz/viewer_idx28.rst

@@ -10,19 +10,46 @@ This node's primary purpose is for display the index information of geometry and
 - Edge indices are drawn on midpoint of the Edge
 - Face indices are drawn at the average location of the Vertices associated with the face.
 
-Additionally 
+Additionally
+
 - the input geometry can be transformed using the Matrix socket.
-- the Node can draw arbitrary (non renderable) text into the 3dview at the location of incoming verts. There must be a one-to-one supply of vertices and text to draw, else the node will decide where to draw the excess text elements.
+- the Node can draw arbitrary (non renderable) text into the 3dview at the
+  location of incoming verts, edges and faces. If incoming data is shorter than
+  number of elements the last element will be displayed on rest elements.
 
-.. image:: https://user-images.githubusercontent.com/619340/127735798-4c3a4222-28ce-418a-b3f0-13c8149a590c.png
+Because it can be difficult to read indices when there are many geometric elements visible there is an option to draw a small background under the text element.
 
-- (available from N Panel) the Node can display the Object index associated with the element ( the first object, first index will be drawn as ``0: 0`` )
+Parameters
+----------
 
-Because it can be difficult to read indices when there are many geometric elements visible there is an option to draw a small background under the text element.
+Activate
+  Enabling the node.
+
+Draw background
+  Hide background around text.
+
+Draw bface
+  (using the Ghost icon in the Node UI) if you attach verts + faces, you can
+  also hide backfacing indices from being displayed. Adding the faces
+  information gives the node enough information to detect what can be seen
+  directly by the viewport "eye" location.
 
-- (using the Ghost icon in the Node UI) if you attach verts + faces, you can also hide backfacing indices from being displayed. Adding the faces information gives the node enough information to detect what can be seen directly by the viewport "eye" location.
+Draw object index
+  (available from N Panel) the Node can display the Object index associated
+  with the element ( the first object, first index will be drawn as ``0: 0`` )
+
+Examples
+--------
+
+Hide text behind geometry
 
 .. image:: https://user-images.githubusercontent.com/619340/127735702-7db6c27a-9f59-4ad4-83f8-44fe96fcbd0c.png
+   :width: 800px
+
+Show custom text
+
+.. image:: https://user-images.githubusercontent.com/619340/127735798-4c3a4222-28ce-418a-b3f0-13c8149a590c.png
+   :width: 800px
 
 
 

nodes/viz/viewer_idx28.py

@@ -203,8 +203,33 @@ def get_geometry(self):
 
             setattr(geom, socket, input_stream)
 
+        prefix_if_needed = lambda obj_index, chars: (f'{obj_index}: {chars}') if self.draw_obj_idx else chars
+
+        fixed_text = []
+        if geom.text:
+            for obj_index, final_verts in enumerate(geom.verts):
+                text_size = max(len(final_verts),
+                                len(geom.edges[obj_index]),
+                                len(geom.faces[obj_index]))
+                text_items = self.get_text_of_correct_length(obj_index, geom, text_size)
+                for text_item in text_items:
+
+                    # yikes, don't feed this function nonsense :)
+
+                    if isinstance(text_item, float):
+                        chars = prefix_if_needed(obj_index, text_item)
+                    elif isinstance(text_item, list) and len(text_item) == 1:
+                        chars = prefix_if_needed(obj_index, text_item[0])
+
+                    else:
+                        # in case it receives [0, 0, 0] or (0, 0, 0).. etc
+                        chars = prefix_if_needed(obj_index, text_item)
+
+                    fixed_text.append(chars)
+
         if not self.draw_bface:
             geom.face_medians, geom.face_normals = self.get_face_extras(geom)
+            geom.text_data = fixed_text
             return geom
 
         else:
@@ -213,15 +238,11 @@ def get_geometry(self):
             display_topology.vert_data = []
             display_topology.edge_data = []
             display_topology.face_data = []
-            display_topology.text_data = []
+            display_topology.text_data = fixed_text
 
             concat_vert = display_topology.vert_data.append
             concat_edge = display_topology.edge_data.append
             concat_face = display_topology.face_data.append
-            concat_text = display_topology.text_data.append
-
-            prefix_if_needed = lambda obj_index, chars: (f'{obj_index}: {chars}') if self.draw_obj_idx else chars
-
 
             for obj_index, final_verts in enumerate(geom.verts):
 
@@ -231,23 +252,6 @@ def get_geometry(self):
                         chars = prefix_if_needed(obj_index, idx)
                         concat_vert((chars, vpos))
 
-                    if geom.text:
-                        text_items = self.get_text_of_correct_length(obj_index, geom, len(final_verts))
-                        for text_item, vpos in zip(text_items, final_verts):
-
-                            # yikes, don't feed this function nonsense :)
-
-                            if isinstance(text_item, float):
-                                chars = prefix_if_needed(obj_index, text_item)
-                            elif isinstance(text_item, list) and len(text_item) == 1:
-                                chars = prefix_if_needed(obj_index, text_item[0])
-
-                            else:
-                                # in case it receives [0, 0, 0] or (0, 0, 0).. etc
-                                chars = prefix_if_needed(obj_index, text_item)
-
-                            concat_text((chars))
-
                 if self.display_edge_index and obj_index < len(geom.edges):
                     for edge_index, (idx1, idx2) in enumerate(geom.edges[obj_index]):
                         loc = final_verts[idx1].lerp(final_verts[idx2], 0.5)

utils/sv_idx_viewer28_draw.py

@@ -120,12 +120,20 @@ def draw_index(index, vec):
                 draw_index(*vidx)
 
         blf.color(font_id, *edge_idx_color)
-        for eidx in geom.edge_data:
-            draw_index(*eidx)
+        if geom.text_data:
+            for text_item, (_, location) in zip(geom.text_data, geom.edge_data):
+                draw_index(text_item, location)
+        else:
+            for eidx in geom.edge_data:
+                draw_index(*eidx)
 
         blf.color(font_id, *face_idx_color)
-        for fidx in geom.face_data:
-            draw_index(*fidx)
+        if geom.text_data:
+            for text_item, (_, location) in zip(geom.text_data, geom.face_data):
+                draw_index(text_item, location)
+        else:
+            for fidx in geom.face_data:
+                draw_index(*fidx)
 
         # if drawing all geometry, we end early.
         return
@@ -169,7 +177,8 @@ def draw_index(index, vec):
                 if hit:
                     if hit[2] == idx:
                         if display_face_index:
-                            draw_index(idx, world_coordinate)
+                            text = geom.text_data[idx] if geom.text_data else idx
+                            draw_index(text, world_coordinate)
 
                         if display_vert_index:
                             for j in polygon:
@@ -183,15 +192,17 @@ def draw_index(index, vec):
 
             blf.color(font_id, *vert_idx_color)
             for idx in cache_vert_indices:
-                draw_index(idx, vertices[idx])
+                text = geom.text_data[idx] if geom.text_data else idx
+                draw_index(text, vertices[idx])
 
             blf.color(font_id, *edge_idx_color)
             for idx, edge in enumerate(edges):
                 sorted_edge = tuple(sorted(edge))
                 if sorted_edge in cache_edge_indices:
                     idx1, idx2 = sorted_edge
                     loc = vertices[idx1].lerp(vertices[idx2], 0.5)
-                    draw_index(idx, loc)
+                    text = geom.text_data[idx] if geom.text_data else idx
+                    draw_index(text, loc)
                     cache_edge_indices.remove(sorted_edge)
 
     except Exception as err:
@@ -308,12 +319,20 @@ def gather_index(index, vec, type_draw):
                 gather_index(vidx[0], vidx[1], 'verts')
 
         # blf.color(font_id, *edge_idx_color)
-        for eidx in geom.edge_data:
-            gather_index(eidx[0], eidx[1], 'edges')
+        if geom.text_data:
+            for text_item, eidx in zip(geom.text_data, geom.edge_data):
+                gather_index(text_item, eidx[1], 'edges')
+        else:
+            for eidx in geom.edge_data:
+                gather_index(eidx[0], eidx[1], 'edges')
 
         # blf.color(font_id, *face_idx_color)
-        for fidx in geom.face_data:
-            gather_index(fidx[0], fidx[1], 'faces')
+        if geom.text_data:
+            for text_item, fidx in zip(geom.text_data, geom.face_data):
+                gather_index(text_item, fidx[1], 'faces')
+        else:
+            for fidx in geom.face_data:
+                gather_index(fidx[0], fidx[1], 'faces')
 
         draw_all_text_at_once(final_draw_data)
         # if drawing all geometry, we end early.
@@ -360,7 +379,8 @@ def gather_index(index, vec, type_draw):
                 if hit:
                     if hit[2] == idx:
                         if display_face_index:
-                            gather_index(idx, world_coordinate, 'faces')
+                            text = geom.text_data[idx] if geom.text_data else idx
+                            gather_index(text, world_coordinate, 'faces')
 
                         if display_vert_index:
                             for j in polygon:
@@ -374,15 +394,17 @@ def gather_index(index, vec, type_draw):
 
             # blf.color(font_id, *vert_idx_color)
             for idx in cache_vert_indices:
-                gather_index(idx, vertices[idx], 'verts')
+                text = geom.text_data[idx] if geom.text_data else idx
+                gather_index(text, vertices[idx], 'verts')
 
             # blf.color(font_id, *edge_idx_color)
             for idx, edge in enumerate(edges):
                 sorted_edge = tuple(sorted(edge))
                 if sorted_edge in cache_edge_indices:
                     idx1, idx2 = sorted_edge
                     loc = vertices[idx1].lerp(vertices[idx2], 0.5)
-                    gather_index(idx, loc, 'edges')
+                    text = geom.text_data[idx] if geom.text_data else idx
+                    gather_index(text, loc, 'edges')
                     cache_edge_indices.remove(sorted_edge)
 
         draw_all_text_at_once(final_draw_data)