Fix T91219: Crash canceling scale keyframes in dope sheet grease pencil

Caused by {rBb0d9e6797fb8}

Ideally `td->loc` should always be set and point to a 3d array.

2 files changed, 12 insertions, 10 deletions

diff --git a/source/blender/editors/transform/transform_convert_action.c b/source/blender/editors/transform/transform_convert_action.c
index 075db30fa61..a6658ae00a3 100644
--- a/source/blender/editors/transform/transform_convert_action.c
+++ b/source/blender/editors/transform/transform_convert_action.c
@@ -51,7 +51,10 @@
 
 /* helper struct for gp-frame transforms */
 typedef struct tGPFtransdata {
-  float val;  /* where transdata writes transform */
+  union {
+    float val;    /* where transdata writes transform */
+    float loc[3]; /* #td->val and #td->loc share the same pointer. */
+  };
   int *sdata; /* pointer to gpf->framenum */
 } tGPFtransdata;
 
@@ -245,8 +248,8 @@ static int GPLayerToTransData(TransData *td,
         tfd->val = (float)gpf->framenum;
         tfd->sdata = &gpf->framenum;
 
-        td->val = td->loc = &tfd->val; /* XXX: It's not a 3d array. */
-        td->ival = td->iloc[0] = (float)gpf->framenum;
+        td->val = td->loc = &tfd->val;
+        td->ival = td->iloc[0] = tfd->val;
 
         td->center[0] = td->ival;
         td->center[1] = ypos;
@@ -279,16 +282,15 @@ static int MaskLayerToTransData(TransData *td,
        masklay_shape = masklay_shape->next) {
     if (is_prop_edit || (masklay_shape->flag & MASK_SHAPE_SELECT)) {
       if (FrameOnMouseSide(side, (float)masklay_shape->frame, cfra)) {
-        /* memory is calloc'ed, so that should zero everything nicely for us */
-        td->val = &tfd->val;
-        td->ival = (float)masklay_shape->frame;
+        tfd->val = (float)masklay_shape->frame;
+        tfd->sdata = &masklay_shape->frame;
+
+        td->val = td->loc = &tfd->val;
+        td->ival = td->iloc[0] = tfd->val;
 
         td->center[0] = td->ival;
         td->center[1] = ypos;
 
-        tfd->val = (float)masklay_shape->frame;
-        tfd->sdata = &masklay_shape->frame;
-
         /* advance td now */
         td++;
         tfd++;
diff --git a/source/blender/editors/transform/transform_generics.c b/source/blender/editors/transform/transform_generics.c
index 9f5e74db501..0dfb229191c 100644
--- a/source/blender/editors/transform/transform_generics.c
+++ b/source/blender/editors/transform/transform_generics.c
@@ -791,7 +791,7 @@ static void restoreElement(TransData *td)
 {
   transdata_restore_basic((TransDataBasic *)td);
 
-  if (td->val) {
+  if (td->val && td->val != td->loc) {
     *td->val = td->ival;
   }