[c][cpp] Port of 4efd63f89cb995cbe4f30358d268a9d0eaf0c9be and 81baef0b5bb181376d15b0208697db8dabce095e

spine-c/spine-c/src/spine/Animation.c

@@ -2042,6 +2042,7 @@ void _spSequenceTimeline_apply(spTimeline *timeline, spSkeleton *skeleton, float
 
 	if (self->attachment->type == SP_ATTACHMENT_REGION) sequence = ((spRegionAttachment *) self->attachment)->sequence;
 	if (self->attachment->type == SP_ATTACHMENT_MESH) sequence = ((spMeshAttachment *) self->attachment)->sequence;
+	if (!sequence) return;
 	index = modeAndIndex >> 4;
 	count = sequence->regions->size;
 	mode = modeAndIndex & 0xf;
@@ -2056,7 +2057,7 @@ void _spSequenceTimeline_apply(spTimeline *timeline, spSkeleton *skeleton, float
 				break;
 			case SP_SEQUENCE_MODE_PINGPONG: {
 				int n = (count << 1) - 2;
-				index %= n;
+				index = n == 0 ? 0 : index % n;
 				if (index >= count) index = n - index;
 				break;
 			}
@@ -2068,7 +2069,7 @@ void _spSequenceTimeline_apply(spTimeline *timeline, spSkeleton *skeleton, float
 				break;
 			case SP_SEQUENCE_MODE_PINGPONGREVERSE: {
 				int n = (count << 1) - 2;
-				index = (index + count - 1) % n;
+				index = n == 0 ? 0 : (index + count - 1) % n;
 				if (index >= count) index = n - index;
 			}
 		}

spine-cpp/spine-cpp/src/spine/SequenceTimeline.cpp

@@ -89,6 +89,7 @@ void SequenceTimeline::apply(Skeleton &skeleton, float lastTime, float time, Vec
 	Sequence *sequence = NULL;
 	if (_attachment->getRTTI().instanceOf(RegionAttachment::rtti)) sequence = ((RegionAttachment *) _attachment)->getSequence();
 	if (_attachment->getRTTI().instanceOf(MeshAttachment::rtti)) sequence = ((MeshAttachment *) _attachment)->getSequence();
+	if (!sequence) return;
 	int index = modeAndIndex >> 4, count = (int) sequence->getRegions().size();
 	int mode = modeAndIndex & 0xf;
 	if (mode != SequenceMode::hold) {
@@ -102,7 +103,7 @@ void SequenceTimeline::apply(Skeleton &skeleton, float lastTime, float time, Vec
 				break;
 			case SequenceMode::pingpong: {
 				int n = (count << 1) - 2;
-				index %= n;
+				index = n == 0 ? 0 : index % n;
 				if (index >= count) index = n - index;
 				break;
 			}
@@ -114,10 +115,10 @@ void SequenceTimeline::apply(Skeleton &skeleton, float lastTime, float time, Vec
 				break;
 			case SequenceMode::pingpongReverse: {
 				int n = (count << 1) - 2;
-				index = (index + count - 1) % n;
+				index = n == 0 ? 0 : (index + count - 1) % n;
 				if (index >= count) index = n - index;
 			}
 		}
 	}
 	slot->setSequenceIndex(index);
-}
+}