Fix transform crash in rare cases

In some cases transform modes would use the custom-data pointer,
other times the transform conversion functions would.

However with some combinations (bone mirror + bend for eg),
both conversion & transform mode would use this pointer causing a crash.

Fix this by having 2 custom-data pointers:
one for the mode, another for the data-type.

This also simplifies time-slide which was conditionally mixing mode/type data in the one array.

1 files changed, 24 insertions, 5 deletions

diff --git a/source/blender/editors/transform/transform.h b/source/blender/editors/transform/transform.h
index f6b4d7da57f..c6d801f7160 100644
--- a/source/blender/editors/transform/transform.h
+++ b/source/blender/editors/transform/transform.h
@@ -357,6 +357,12 @@ typedef struct MouseInput {
 	} virtual_mval;
 } MouseInput;
 
+typedef struct TransCustomData {
+	void       *data;
+	void      (*free_cb)(struct TransInfo *, struct TransCustomData *);
+	unsigned int use_free : 1;
+} TransCustomData;
+
 typedef struct TransInfo {
 	int         mode;           /* current mode                         */
 	int	        flag;           /* generic flags for special behaviors  */
@@ -408,8 +414,22 @@ typedef struct TransInfo {
 
 	struct Object *poseobj;		/* if t->flag & T_POSE, this denotes pose object */
 
-	void       *customData;		/* Per Transform custom data */
-	void  	  (*customFree)(struct TransInfo *); /* if a special free function is needed */
+	/**
+	 * Rule of thumb for choosing between mode/type:
+	 * - If transform mode uses the data, assign to `mode`
+	 *   (typically in transform.c).
+	 * - If conversion uses the data as an extension to the #TransData, assign to `type`
+	 *   (typically in transform_conversion.c).
+	 */
+	struct {
+		/* owned by the mode (grab, scale, bend... )*/
+		union {
+			TransCustomData mode, first_elem;
+		};
+		/* owned by the type (mesh, armature, nla...) */
+		TransCustomData type;
+	} custom;
+#define TRANS_CUSTOM_DATA_ELEM_MAX (sizeof(((TransInfo *)NULL)->custom) / sizeof(TransCustomData))
 
 	/*************** NEW STUFF *********************/
 	short		launch_event; 	/* event type used to launch transform */
@@ -484,7 +504,6 @@ typedef struct TransInfo {
 #define T_2D_EDIT			(1 << 15)
 #define T_CLIP_UV			(1 << 16)
 
-#define T_FREE_CUSTOMDATA	(1 << 17)
 	/* auto-ik is on */
 #define T_AUTOIK			(1 << 18)
 
@@ -758,11 +777,11 @@ int getTransformOrientation_ex(const struct bContext *C, float normal[3], float
 int getTransformOrientation(const struct bContext *C, float normal[3], float plane[3]);
 
 void freeEdgeSlideTempFaces(EdgeSlideData *sld);
-void freeEdgeSlideVerts(TransInfo *t);
+void freeEdgeSlideVerts(TransInfo *t, TransCustomData *custom_data);
 void projectEdgeSlideData(TransInfo *t, bool is_final);
 
 void freeVertSlideTempFaces(VertSlideData *sld);
-void freeVertSlideVerts(TransInfo *t);
+void freeVertSlideVerts(TransInfo *t, TransCustomData *custom_data);
 void projectVertSlideData(TransInfo *t, bool is_final);