2 files changed, 29 insertions, 12 deletions

diff --git a/drivers/gles3/storage/mesh_storage.cpp b/drivers/gles3/storage/mesh_storage.cpp
index 25e020b892..e5080b39a3 100644
--- a/drivers/gles3/storage/mesh_storage.cpp
+++ b/drivers/gles3/storage/mesh_storage.cpp
@@ -351,6 +351,7 @@ void MeshStorage::mesh_add_surface(RID p_mesh, const RS::SurfaceData &p_surface)
 
 	s->aabb = new_surface.aabb;
 	s->bone_aabbs = new_surface.bone_aabbs; //only really useful for returning them.
+	s->mesh_to_skeleton_xform = p_surface.mesh_to_skeleton_xform;
 
 	s->uv_scale = new_surface.uv_scale;
 
@@ -572,6 +573,7 @@ RS::SurfaceData MeshStorage::mesh_get_surface(RID p_mesh, int p_surface) const {
 	}
 
 	sd.bone_aabbs = s.bone_aabbs;
+	sd.mesh_to_skeleton_xform = s.mesh_to_skeleton_xform;
 
 	if (mesh->blend_shape_count) {
 		sd.blend_shape_data = Vector<uint8_t>();
@@ -625,15 +627,16 @@ AABB MeshStorage::mesh_get_aabb(RID p_mesh, RID p_skeleton) {
 
 	for (uint32_t i = 0; i < mesh->surface_count; i++) {
 		AABB laabb;
-		if ((mesh->surfaces[i]->format & RS::ARRAY_FORMAT_BONES) && mesh->surfaces[i]->bone_aabbs.size()) {
-			int bs = mesh->surfaces[i]->bone_aabbs.size();
-			const AABB *skbones = mesh->surfaces[i]->bone_aabbs.ptr();
+		const Mesh::Surface &surface = *mesh->surfaces[i];
+		if ((surface.format & RS::ARRAY_FORMAT_BONES) && surface.bone_aabbs.size()) {
+			int bs = surface.bone_aabbs.size();
+			const AABB *skbones = surface.bone_aabbs.ptr();
 
 			int sbs = skeleton->size;
 			ERR_CONTINUE(bs > sbs);
 			const float *baseptr = skeleton->data.ptr();
 
-			bool first = true;
+			bool found_bone_aabb = false;
 
 			if (skeleton->use_2d) {
 				for (int j = 0; j < bs; j++) {
@@ -653,11 +656,13 @@ AABB MeshStorage::mesh_get_aabb(RID p_mesh, RID p_skeleton) {
 					mtx.basis.rows[1][1] = dataptr[5];
 					mtx.origin.y = dataptr[7];
 
-					AABB baabb = mtx.xform(skbones[j]);
+					// Transform bounds to skeleton's space before applying animation data.
+					AABB baabb = surface.mesh_to_skeleton_xform.xform(skbones[j]);
+					baabb = mtx.xform(baabb);
 
-					if (first) {
+					if (!found_bone_aabb) {
 						laabb = baabb;
-						first = false;
+						found_bone_aabb = true;
 					} else {
 						laabb.merge_with(baabb);
 					}
@@ -685,21 +690,29 @@ AABB MeshStorage::mesh_get_aabb(RID p_mesh, RID p_skeleton) {
 					mtx.basis.rows[2][2] = dataptr[10];
 					mtx.origin.z = dataptr[11];
 
-					AABB baabb = mtx.xform(skbones[j]);
-					if (first) {
+					// Transform bounds to skeleton's space before applying animation data.
+					AABB baabb = surface.mesh_to_skeleton_xform.xform(skbones[j]);
+					baabb = mtx.xform(baabb);
+
+					if (!found_bone_aabb) {
 						laabb = baabb;
-						first = false;
+						found_bone_aabb = true;
 					} else {
 						laabb.merge_with(baabb);
 					}
 				}
 			}
 
+			if (found_bone_aabb) {
+				// Transform skeleton bounds back to mesh's space if any animated AABB applied.
+				laabb = surface.mesh_to_skeleton_xform.affine_inverse().xform(laabb);
+			}
+
 			if (laabb.size == Vector3()) {
-				laabb = mesh->surfaces[i]->aabb;
+				laabb = surface.aabb;
 			}
 		} else {
-			laabb = mesh->surfaces[i]->aabb;
+			laabb = surface.aabb;
 		}
 
 		if (i == 0) {
diff --git a/drivers/gles3/storage/mesh_storage.h b/drivers/gles3/storage/mesh_storage.h
index f52a60d067..217c4dabf0 100644
--- a/drivers/gles3/storage/mesh_storage.h
+++ b/drivers/gles3/storage/mesh_storage.h
@@ -106,6 +106,10 @@ struct Mesh {
 
 		Vector<AABB> bone_aabbs;
 
+		// Transform used in runtime bone AABBs compute.
+		// As bone AABBs are saved in Mesh space, but bones animation is in Skeleton space.
+		Transform3D mesh_to_skeleton_xform;
+
 		Vector4 uv_scale;
 
 		struct BlendShape {