Fix T95467: Textures disappear when going to Edit Mesh on Solid Texture mode

The check for existence of custom data layers did not take wrapper nature of
mesh into account.

Quickest and safest for 3.1 solution is to take care of branching of checks
in the draw manager.

Ideally both wrapper and mesh access will happen via the same public API
without branching in the "user" code. That is something outside of the fix
for the coming release though.

Differential Revision: https://developer.blender.org/D14013

1 files changed, 28 insertions, 5 deletions

diff --git a/source/blender/draw/engines/workbench/workbench_engine.c b/source/blender/draw/engines/workbench/workbench_engine.c
index 0a0c20b0d6a..4a8c248a8e9 100644
--- a/source/blender/draw/engines/workbench/workbench_engine.c
+++ b/source/blender/draw/engines/workbench/workbench_engine.c
@@ -28,6 +28,7 @@
 
 #include "BLI_alloca.h"
 
+#include "BKE_editmesh.h"
 #include "BKE_modifier.h"
 #include "BKE_object.h"
 #include "BKE_paint.h"
@@ -239,6 +240,26 @@ static void workbench_cache_hair_populate(WORKBENCH_PrivateData *wpd,
   DRW_shgroup_hair_create_sub(ob, psys, md, grp, NULL);
 }
 
+static const CustomData *workbench_mesh_get_loop_custom_data(const Mesh *mesh)
+{
+  if (mesh->runtime.wrapper_type == ME_WRAPPER_TYPE_BMESH) {
+    BLI_assert(mesh->edit_mesh != NULL);
+    BLI_assert(mesh->edit_mesh->bm != NULL);
+    return &mesh->edit_mesh->bm->ldata;
+  }
+  return &mesh->ldata;
+}
+
+static const CustomData *workbench_mesh_get_vert_custom_data(const Mesh *mesh)
+{
+  if (mesh->runtime.wrapper_type == ME_WRAPPER_TYPE_BMESH) {
+    BLI_assert(mesh->edit_mesh != NULL);
+    BLI_assert(mesh->edit_mesh->bm != NULL);
+    return &mesh->edit_mesh->bm->vdata;
+  }
+  return &mesh->vdata;
+}
+
 /**
  * Decide what color-type to draw the object with.
  * In some cases it can be overwritten by #workbench_material_setup().
@@ -251,6 +272,8 @@ static eV3DShadingColorType workbench_color_type_get(WORKBENCH_PrivateData *wpd,
 {
   eV3DShadingColorType color_type = wpd->shading.color_type;
   const Mesh *me = (ob->type == OB_MESH) ? ob->data : NULL;
+  const CustomData *ldata = workbench_mesh_get_loop_custom_data(me);
+  const CustomData *vdata = workbench_mesh_get_vert_custom_data(me);
 
   const DRWContextState *draw_ctx = DRW_context_state_get();
   const bool is_active = (ob == draw_ctx->obact);
@@ -264,19 +287,19 @@ static eV3DShadingColorType workbench_color_type_get(WORKBENCH_PrivateData *wpd,
     if (ob->dt < OB_TEXTURE) {
       color_type = V3D_SHADING_MATERIAL_COLOR;
     }
-    else if ((me == NULL) || (me->mloopuv == NULL)) {
+    else if ((me == NULL) || !CustomData_has_layer(ldata, CD_MLOOPUV)) {
       /* Disable color mode if data layer is unavailable. */
       color_type = V3D_SHADING_MATERIAL_COLOR;
     }
   }
   else if (color_type == V3D_SHADING_VERTEX_COLOR) {
     if (U.experimental.use_sculpt_vertex_colors) {
-      if ((me == NULL) || !CustomData_has_layer(&me->vdata, CD_PROP_COLOR)) {
+      if ((me == NULL) || !CustomData_has_layer(vdata, CD_PROP_COLOR)) {
         color_type = V3D_SHADING_OBJECT_COLOR;
       }
     }
     else {
-      if ((me == NULL) || !CustomData_has_layer(&me->ldata, CD_MLOOPCOL)) {
+      if ((me == NULL) || !CustomData_has_layer(ldata, CD_MLOOPCOL)) {
         color_type = V3D_SHADING_OBJECT_COLOR;
       }
     }
@@ -291,13 +314,13 @@ static eV3DShadingColorType workbench_color_type_get(WORKBENCH_PrivateData *wpd,
 
   if (!is_sculpt_pbvh && !is_render) {
     /* Force texture or vertex mode if object is in paint mode. */
-    if (is_texpaint_mode && me && me->mloopuv) {
+    if (is_texpaint_mode && me && CustomData_has_layer(ldata, CD_MLOOPUV)) {
       color_type = V3D_SHADING_TEXTURE_COLOR;
       if (r_texpaint_mode) {
         *r_texpaint_mode = true;
       }
     }
-    else if (is_vertpaint_mode && me && me->mloopcol) {
+    else if (is_vertpaint_mode && me && CustomData_has_layer(ldata, CD_MLOOPCOL)) {
       color_type = V3D_SHADING_VERTEX_COLOR;
     }
   }