[Bf-blender-cvs] [b6279b74156] blender-v2.83-release: Fix T75794: Light point gizmo translate jumps

[Campbell Barton]

Commit: b6279b74156e1f6d17dc0fa324aee347b26c9bd0
Author: Campbell Barton
Date:   Fri Apr 17 18:48:33 2020 +1000
Branches: blender-v2.83-release
https://developer.blender.org/rBb6279b74156e1f6d17dc0fa324aee347b26c9bd0

Fix T75794: Light point gizmo translate jumps

Holding Ctrl while dragging the light point gizmo would use
uninitialized stack memory if the normal had not been
initialized by a surface.

Now holding Ctrl can be used to drag,
even when there is no surface to orient to.

===================================================================

M	source/blender/editors/object/object_transform.c

===================================================================

diff --git a/source/blender/editors/object/object_transform.c b/source/blender/editors/object/object_transform.c
index 46245d21d5b..7b3955a0cf8 100644
--- a/source/blender/editors/object/object_transform.c
+++ b/source/blender/editors/object/object_transform.c
@@ -1912,7 +1912,7 @@ static int object_transform_axis_target_modal(bContext *C, wmOperator *op, const
               normal_found = true;
             }
 
-            if (normal_found) {
+            {
 #ifdef USE_RELATIVE_ROTATION
               if (is_translate_init && xfd->object_data_len > 1) {
                 float xform_rot_offset_inv_first[3][3];
@@ -1941,16 +1941,26 @@ static int object_transform_axis_target_modal(bContext *C, wmOperator *op, const
                   item->xform_dist = len_v3v3(item->ob->obmat[3], location_world);
                   normalize_v3_v3(ob_axis, item->ob->obmat[2]);
                   /* Scale to avoid adding distance when moving between surfaces. */
-                  float scale = fabsf(dot_v3v3(ob_axis, normal));
-                  item->xform_dist *= scale;
+                  if (normal_found) {
+                    float scale = fabsf(dot_v3v3(ob_axis, normal));
+                    item->xform_dist *= scale;
+                  }
                 }
 
                 float target_normal[3];
-                copy_v3_v3(target_normal, normal);
+
+                if (normal_found) {
+                  copy_v3_v3(target_normal, normal);
+                }
+                else {
+                  normalize_v3_v3(target_normal, item->ob->obmat[2]);
+                }
 
 #ifdef USE_RELATIVE_ROTATION
-                if (i != 0) {
-                  mul_m3_v3(item->xform_rot_offset, target_normal);
+                if (normal_found) {
+                  if (i != 0) {
+                    mul_m3_v3(item->xform_rot_offset, target_normal);
+                  }
                 }
 #endif
                 {
@@ -1967,8 +1977,10 @@ static int object_transform_axis_target_modal(bContext *C, wmOperator *op, const
                     item->ob, item->rot_mat, item->rot_mat[2], location_world);
                 WM_event_add_notifier(C, NC_OBJECT | ND_TRANSFORM, item->ob);
               }
-              copy_v3_v3(xfd->prev.normal, normal);
-              xfd->prev.is_normal_valid = true;
+              if (normal_found) {
+                copy_v3_v3(xfd->prev.normal, normal);
+                xfd->prev.is_normal_valid = true;
+              }
             }
           }
           else {