Fix T97330: UV points missing with some modifiers

When extracting UV point indices, only the vertex points coming from the
original geometry should be drawn. For this, the routines (for subdivision
and coarse meshes) would only consider a vertex to be real if the extraction
type is `MAPPED`, and that an origin index layer on the vertices exist
with a valid origin index for the current vertex.

However, if the extraction type is `MESH`, which can happen with for
example an empty Geometry Node modifier, or with deferred subdivision,
this would consider every vertex to not be "real" and therefore hidden from
the UV editor.

This reworks the condition for "realness" to also consider a vertex to be
real if there is no origin layer on the vertices. The check on the extraction
type is removed as it becomes redundant.

This only modifies the check in the UV data extraction for point indices,
however similar checks exist throughout the extraction code, these will
be dealt with separately in master.

Differential Revision: https://developer.blender.org/D14773

1 files changed, 5 insertions, 9 deletions

diff --git a/source/blender/draw/intern/mesh_extractors/extract_mesh_ibo_edituv.cc b/source/blender/draw/intern/mesh_extractors/extract_mesh_ibo_edituv.cc
index 43aa52f08c8..2c4e7bfa802 100644
--- a/source/blender/draw/intern/mesh_extractors/extract_mesh_ibo_edituv.cc
+++ b/source/blender/draw/intern/mesh_extractors/extract_mesh_ibo_edituv.cc
@@ -387,8 +387,7 @@ static void extract_edituv_points_iter_poly_mesh(const MeshRenderData *mr,
   for (int ml_index = mp->loopstart; ml_index < ml_index_end; ml_index += 1) {
     const MLoop *ml = &mloop[ml_index];
 
-    const bool real_vert = (mr->extract_type == MR_EXTRACT_MAPPED && (mr->v_origindex) &&
-                            mr->v_origindex[ml->v] != ORIGINDEX_NONE);
+    const bool real_vert = !mr->v_origindex || mr->v_origindex[ml->v] != ORIGINDEX_NONE;
     edituv_point_add(
         data, ((mp->flag & ME_HIDE) != 0) || !real_vert, (mp->flag & ME_FACE_SEL) != 0, ml_index);
   }
@@ -449,9 +448,8 @@ static void extract_edituv_points_iter_subdiv_mesh(const DRWSubdivCache *subdiv_
   uint end_loop_idx = (subdiv_quad_index + 1) * 4;
   for (uint i = start_loop_idx; i < end_loop_idx; i++) {
     const int vert_origindex = subdiv_loop_vert_index[i];
-    const bool real_vert = (mr->extract_type == MR_EXTRACT_MAPPED && (mr->v_origindex) &&
-                            vert_origindex != -1 &&
-                            mr->v_origindex[vert_origindex] != ORIGINDEX_NONE);
+    const bool real_vert = !mr->v_origindex || (vert_origindex != -1 &&
+                                                mr->v_origindex[vert_origindex] != ORIGINDEX_NONE);
     edituv_point_add(data,
                      ((coarse_quad->flag & ME_HIDE) != 0) || !real_vert,
                      (coarse_quad->flag & ME_FACE_SEL) != 0,
@@ -543,8 +541,7 @@ static void extract_edituv_fdots_iter_poly_mesh(const MeshRenderData *mr,
     for (int ml_index = mp->loopstart; ml_index < ml_index_end; ml_index += 1) {
       const MLoop *ml = &mloop[ml_index];
 
-      const bool real_fdot = (mr->extract_type == MR_EXTRACT_MAPPED && mr->p_origindex &&
-                              mr->p_origindex[mp_index] != ORIGINDEX_NONE);
+      const bool real_fdot = !mr->p_origindex || (mr->p_origindex[mp_index] != ORIGINDEX_NONE);
       const bool subd_fdot = BLI_BITMAP_TEST(facedot_tags, ml->v);
       edituv_facedot_add(data,
                          ((mp->flag & ME_HIDE) != 0) || !real_fdot || !subd_fdot,
@@ -553,8 +550,7 @@ static void extract_edituv_fdots_iter_poly_mesh(const MeshRenderData *mr,
     }
   }
   else {
-    const bool real_fdot = (mr->extract_type == MR_EXTRACT_MAPPED && mr->p_origindex &&
-                            mr->p_origindex[mp_index] != ORIGINDEX_NONE);
+    const bool real_fdot = !mr->p_origindex || (mr->p_origindex[mp_index] != ORIGINDEX_NONE);
     edituv_facedot_add(
         data, ((mp->flag & ME_HIDE) != 0) || !real_fdot, (mp->flag & ME_FACE_SEL) != 0, mp_index);
   }