Snap and Placement Gizmo Refactor

Move most of the gizmo snap and placement code to `view_cursor_snap.c`.

Simplify and extend the snap API.

Differential Revision: https://developer.blender.org/D12868

2 files changed, 34 insertions, 23 deletions

diff --git a/source/blender/editors/transform/transform_snap.c b/source/blender/editors/transform/transform_snap.c
index 2e1e8eb4ca4..7f27d5fb180 100644
--- a/source/blender/editors/transform/transform_snap.c
+++ b/source/blender/editors/transform/transform_snap.c
@@ -48,6 +48,7 @@
 #include "ED_node.h"
 #include "ED_transform_snap_object_context.h"
 #include "ED_uvedit.h"
+#include "ED_view3d.h"
 
 #include "UI_resources.h"
 #include "UI_view2d.h"
@@ -247,7 +248,7 @@ void drawSnapping(const struct bContext *C, TransInfo *t)
         loc_cur = t->tsnap.snapPoint;
       }
 
-      ED_gizmotypes_snap_3d_draw_util(
+      ED_view3d_cursor_snap_draw_util(
           rv3d, loc_prev, loc_cur, normal, col, activeCol, t->tsnap.snapElem);
 
       GPU_depth_test(GPU_DEPTH_LESS_EQUAL);
@@ -1243,7 +1244,7 @@ short snapObjectsTransform(
     TransInfo *t, const float mval[2], float *dist_px, float r_loc[3], float r_no[3])
 {
   float *target = (t->tsnap.status & TARGET_INIT) ? t->tsnap.snapTarget : t->center_global;
-  return ED_transform_snap_object_project_view3d_ex(
+  return ED_transform_snap_object_project_view3d(
       t->tsnap.object_context,
       t->depsgraph,
       t->region,
@@ -1259,10 +1260,7 @@ short snapObjectsTransform(
       target,
       dist_px,
       r_loc,
-      r_no,
-      NULL,
-      NULL,
-      NULL);
+      r_no);
 }
 
 /** \} */
diff --git a/source/blender/editors/transform/transform_snap_object.c b/source/blender/editors/transform/transform_snap_object.c
index 5f9250e87f7..17326001a99 100644
--- a/source/blender/editors/transform/transform_snap_object.c
+++ b/source/blender/editors/transform/transform_snap_object.c
@@ -3020,7 +3020,8 @@ static short transform_snap_context_project_view3d_mixed_impl(
     float r_no[3],
     int *r_index,
     Object **r_ob,
-    float r_obmat[4][4])
+    float r_obmat[4][4],
+    float r_face_nor[3])
 {
   BLI_assert((snap_to_flag & (SCE_SNAP_MODE_VERTEX | SCE_SNAP_MODE_EDGE | SCE_SNAP_MODE_FACE |
                               SCE_SNAP_MODE_EDGE_MIDPOINT | SCE_SNAP_MODE_EDGE_PERPENDICULAR)) !=
@@ -3067,22 +3068,27 @@ static short transform_snap_context_project_view3d_mixed_impl(
                              &ob_eval,
                              obmat,
                              NULL);
+    if (has_hit) {
+      if (r_face_nor) {
+        copy_v3_v3(r_face_nor, no);
+      }
 
-    if (has_hit && (snap_to_flag & SCE_SNAP_MODE_FACE)) {
-      retval = SCE_SNAP_MODE_FACE;
+      if ((snap_to_flag & SCE_SNAP_MODE_FACE)) {
+        retval = SCE_SNAP_MODE_FACE;
 
-      copy_v3_v3(r_loc, loc);
-      if (r_no) {
-        copy_v3_v3(r_no, no);
-      }
-      if (r_ob) {
-        *r_ob = ob_eval;
-      }
-      if (r_obmat) {
-        copy_m4_m4(r_obmat, obmat);
-      }
-      if (r_index) {
-        *r_index = index;
+        copy_v3_v3(r_loc, loc);
+        if (r_no) {
+          copy_v3_v3(r_no, no);
+        }
+        if (r_ob) {
+          *r_ob = ob_eval;
+        }
+        if (r_obmat) {
+          copy_m4_m4(r_obmat, obmat);
+        }
+        if (r_index) {
+          *r_index = index;
+        }
       }
     }
   }
@@ -3182,6 +3188,10 @@ static short transform_snap_context_project_view3d_mixed_impl(
       if (r_index) {
         *r_index = index;
       }
+      if (r_face_nor && !has_hit) {
+        /* Fallback. */
+        copy_v3_v3(r_face_nor, no);
+      }
 
       *dist_px = dist_px_tmp;
     }
@@ -3203,7 +3213,8 @@ short ED_transform_snap_object_project_view3d_ex(SnapObjectContext *sctx,
                                                  float r_no[3],
                                                  int *r_index,
                                                  Object **r_ob,
-                                                 float r_obmat[4][4])
+                                                 float r_obmat[4][4],
+                                                 float r_face_nor[3])
 {
   return transform_snap_context_project_view3d_mixed_impl(sctx,
                                                           depsgraph,
@@ -3218,7 +3229,8 @@ short ED_transform_snap_object_project_view3d_ex(SnapObjectContext *sctx,
                                                           r_no,
                                                           r_index,
                                                           r_ob,
-                                                          r_obmat);
+                                                          r_obmat,
+                                                          r_face_nor);
 }
 
 /**
@@ -3259,6 +3271,7 @@ bool ED_transform_snap_object_project_view3d(SnapObjectContext *sctx,
                                                     r_no,
                                                     NULL,
                                                     NULL,
+                                                    NULL,
                                                     NULL) != 0;
 }