Fix T84808: Individual projection works even when snap options don't affect the transform mode

Individual projection is a different branch of snap and always projects
the transformed elements on the surface of objects.

Perhaps this option should be limited to the Move mode due to similarity.

But in order not to change the current behavior too much, this commit only
disables this option in modes not affected by snap.

1 files changed, 64 insertions, 54 deletions

diff --git a/source/blender/editors/transform/transform_snap.c b/source/blender/editors/transform/transform_snap.c
index c19dd4598cf..508189c5d77 100644
--- a/source/blender/editors/transform/transform_snap.c
+++ b/source/blender/editors/transform/transform_snap.c
@@ -299,83 +299,93 @@ eRedrawFlag handleSnapping(TransInfo *t, const wmEvent *event)
 
 void applyProject(TransInfo *t)
 {
-  /* XXX FLICKER IN OBJECT MODE */
-  if ((t->tsnap.project) && activeSnap(t) && (t->flag & T_NO_PROJECT) == 0) {
-    float tvec[3];
-    int i;
+  if (!t->tsnap.project) {
+    return;
+  }
 
-    FOREACH_TRANS_DATA_CONTAINER (t, tc) {
-      TransData *td = tc->data;
-      for (i = 0; i < tc->data_len; i++, td++) {
-        float iloc[3], loc[3], no[3];
-        float mval_fl[2];
-        if (td->flag & TD_SKIP) {
-          continue;
-        }
+  if (!activeSnap(t) || (t->flag & T_NO_PROJECT)) {
+    return;
+  }
 
-        if ((t->flag & T_PROP_EDIT) && (td->factor == 0.0f)) {
-          continue;
-        }
+  if (doForceIncrementSnap(t)) {
+    return;
+  }
 
-        copy_v3_v3(iloc, td->loc);
-        if (tc->use_local_mat) {
-          mul_m4_v3(tc->mat, iloc);
-        }
-        else if (t->flag & T_OBJECT) {
-          BKE_object_eval_transform_all(t->depsgraph, t->scene, td->ob);
-          copy_v3_v3(iloc, td->ob->obmat[3]);
-        }
+  float tvec[3];
+  int i;
+
+  /* XXX FLICKER IN OBJECT MODE */
+  FOREACH_TRANS_DATA_CONTAINER (t, tc) {
+    TransData *td = tc->data;
+    for (i = 0; i < tc->data_len; i++, td++) {
+      float iloc[3], loc[3], no[3];
+      float mval_fl[2];
+      if (td->flag & TD_SKIP) {
+        continue;
+      }
+
+      if ((t->flag & T_PROP_EDIT) && (td->factor == 0.0f)) {
+        continue;
+      }
 
-        if (ED_view3d_project_float_global(t->region, iloc, mval_fl, V3D_PROJ_TEST_NOP) ==
-            V3D_PROJ_RET_OK) {
-          if (ED_transform_snap_object_project_view3d(
-                  t->tsnap.object_context,
-                  t->depsgraph,
-                  SCE_SNAP_MODE_FACE,
-                  &(const struct SnapObjectParams){
-                      .snap_select = t->tsnap.modeSelect,
-                      .use_object_edit_cage = (t->flag & T_EDIT) != 0,
-                      .use_occlusion_test = false,
-                      .use_backface_culling = t->tsnap.use_backface_culling,
-                  },
-                  mval_fl,
-                  NULL,
-                  0,
-                  loc,
-                  no)) {
+      copy_v3_v3(iloc, td->loc);
+      if (tc->use_local_mat) {
+        mul_m4_v3(tc->mat, iloc);
+      }
+      else if (t->flag & T_OBJECT) {
+        BKE_object_eval_transform_all(t->depsgraph, t->scene, td->ob);
+        copy_v3_v3(iloc, td->ob->obmat[3]);
+      }
+
+      if (ED_view3d_project_float_global(t->region, iloc, mval_fl, V3D_PROJ_TEST_NOP) ==
+          V3D_PROJ_RET_OK) {
+        if (ED_transform_snap_object_project_view3d(
+                t->tsnap.object_context,
+                t->depsgraph,
+                SCE_SNAP_MODE_FACE,
+                &(const struct SnapObjectParams){
+                    .snap_select = t->tsnap.modeSelect,
+                    .use_object_edit_cage = (t->flag & T_EDIT) != 0,
+                    .use_occlusion_test = false,
+                    .use_backface_culling = t->tsnap.use_backface_culling,
+                },
+                mval_fl,
+                NULL,
+                0,
+                loc,
+                no)) {
 #if 0
             if (tc->use_local_mat) {
               mul_m4_v3(tc->imat, loc);
             }
 #endif
 
-            sub_v3_v3v3(tvec, loc, iloc);
+          sub_v3_v3v3(tvec, loc, iloc);
 
-            mul_m3_v3(td->smtx, tvec);
+          mul_m3_v3(td->smtx, tvec);
 
-            add_v3_v3(td->loc, tvec);
+          add_v3_v3(td->loc, tvec);
 
-            if (t->tsnap.align && (t->flag & T_OBJECT)) {
-              /* handle alignment as well */
-              const float *original_normal;
-              float mat[3][3];
+          if (t->tsnap.align && (t->flag & T_OBJECT)) {
+            /* handle alignment as well */
+            const float *original_normal;
+            float mat[3][3];
 
-              /* In pose mode, we want to align normals with Y axis of bones... */
-              original_normal = td->axismtx[2];
+            /* In pose mode, we want to align normals with Y axis of bones... */
+            original_normal = td->axismtx[2];
 
-              rotation_between_vecs_to_mat3(mat, original_normal, no);
+            rotation_between_vecs_to_mat3(mat, original_normal, no);
 
-              transform_data_ext_rotate(td, mat, true);
+            transform_data_ext_rotate(td, mat, true);
 
-              /* TODO support constraints for rotation too? see ElementRotation */
-            }
+            /* TODO support constraints for rotation too? see ElementRotation */
           }
         }
+      }
 
 #if 0 /* TODO: sipport this? */
          constraintTransLim(t, td);
 #endif
-      }
     }
   }
 }