Fix editmesh GLSL tangent drawing

The generic tangent calculation relied on CDDM arrays which aren't available in edit-mode.

Add a tangent calculation callback, which has its own implementation for editmesh data.

1 files changed, 3 insertions, 1 deletions

diff --git a/source/blender/blenkernel/BKE_DerivedMesh.h b/source/blender/blenkernel/BKE_DerivedMesh.h
index 2eac1a07daf..e6d5b89e6ef 100644
--- a/source/blender/blenkernel/BKE_DerivedMesh.h
+++ b/source/blender/blenkernel/BKE_DerivedMesh.h
@@ -209,6 +209,8 @@ struct DerivedMesh {
 	void (*calcLoopNormalsSpaceArray)(DerivedMesh *dm, const bool use_split_normals, const float split_angle,
 	                                  struct MLoopNorSpaceArray *r_lnors_spacearr);
 
+	void (*calcLoopTangents)(DerivedMesh *dm);
+
 	/** Recalculates mesh tessellation */
 	void (*recalcTessellation)(DerivedMesh *dm);
 
@@ -771,7 +773,7 @@ void DM_vertex_attributes_from_gpu(
 
 void DM_draw_attrib_vertex(DMVertexAttribs *attribs, int a, int index, int vert, int loop);
 
-void DM_add_tangent_layer(DerivedMesh *dm);
+void DM_calc_loop_tangents(DerivedMesh *dm);
 void DM_calc_auto_bump_scale(DerivedMesh *dm);
 
 /** Set object's bounding box based on DerivedMesh min/max data */