Fix T56360: metaball viewport checkbox crash.

Do same as for other geometry types to compute bbox, instead of blindly
returning NULL `ob->bb`...

1 files changed, 17 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/mball.c b/source/blender/blenkernel/intern/mball.c
index bc2d7ed79d5..5e4f5614370 100644
--- a/source/blender/blenkernel/intern/mball.c
+++ b/source/blender/blenkernel/intern/mball.c
@@ -238,6 +238,23 @@ void BKE_mball_texspace_calc(Object *ob)
 	bb->flag &= ~BOUNDBOX_DIRTY;
 }
 
+/** Return or compute bbox for given metaball object. */
+BoundBox *BKE_mball_boundbox_get(Object *ob)
+{
+	BLI_assert(ob->type == OB_MBALL);
+
+	if (ob->bb != NULL && (ob->bb->flag & BOUNDBOX_DIRTY) == 0) {
+		return ob->bb;
+	}
+
+	/* This should always only be called with evaluated objects, but currently RNA is a problem here... */
+	if (ob->runtime.curve_cache != NULL) {
+		BKE_mball_texspace_calc(ob);
+	}
+
+	return ob->bb;
+}
+
 float *BKE_mball_make_orco(Object *ob, ListBase *dispbase)
 {
 	BoundBox *bb;