1 files changed, 18 insertions, 13 deletions

diff --git a/source/blender/editors/mesh/editmesh_slide.c b/source/blender/editors/mesh/editmesh_slide.c
index bd1d13f3528..e42b95c6013 100644
--- a/source/blender/editors/mesh/editmesh_slide.c
+++ b/source/blender/editors/mesh/editmesh_slide.c
@@ -381,22 +381,23 @@ static BMEdge *vtx_slide_nrst_in_frame(VertexSlideOp *vso, const float mval[2])
 		BMEdge *edge = NULL;
 		
 		float v1_proj[3], v2_proj[3];
-		float dist = 0;
 		float min_dist = FLT_MAX;
 
 		for (i = 0; i < vso->disk_edges; i++) {
 			edge = vso->edge_frame[i];
 
 			mul_v3_m4v3(v1_proj, vso->obj->obmat, edge->v1->co);
-			ED_view3d_project_float_noclip(vso->active_region, v1_proj, v1_proj);
-
 			mul_v3_m4v3(v2_proj, vso->obj->obmat, edge->v2->co);
-			ED_view3d_project_float_noclip(vso->active_region, v2_proj, v2_proj);
 
-			dist = dist_to_line_segment_v2(mval, v1_proj, v2_proj);
-			if (dist < min_dist) {
-				min_dist = dist;
-				cl_edge = edge;
+			/* we could use ED_view3d_project_float_object here, but for now dont since we dont have the context */
+			if ((ED_view3d_project_float_global(vso->active_region, v1_proj, v1_proj, V3D_PROJ_TEST_NOP) == V3D_PROJ_RET_SUCCESS) &&
+			    (ED_view3d_project_float_global(vso->active_region, v2_proj, v2_proj, V3D_PROJ_TEST_NOP) == V3D_PROJ_RET_SUCCESS))
+			{
+				const float dist = dist_to_line_segment_v2(mval, v1_proj, v2_proj);
+				if (dist < min_dist) {
+					min_dist = dist;
+					cl_edge = edge;
+				}
 			}
 		}
 	}
@@ -448,17 +449,21 @@ static void vtx_slide_update(VertexSlideOp *vso, wmEvent *event)
 		/* Calculate interpolation value for preview */
 		float t_val;
 
-		float mval_float[] = { (float)event->mval[0], (float)event->mval[1]};
+		float mval_float[2] = { (float)event->mval[0], (float)event->mval[1]};
 		float closest_2d[2];
 
 		other = BM_edge_other_vert(edge, vso->start_vtx);
 
 		/* Project points onto screen and do interpolation in 2D */
 		mul_v3_m4v3(start_vtx_proj, vso->obj->obmat, vso->start_vtx->co);
-		ED_view3d_project_float_noclip(vso->active_region, start_vtx_proj, start_vtx_proj);
-
 		mul_v3_m4v3(edge_other_proj, vso->obj->obmat, other->co);
-		ED_view3d_project_float_noclip(vso->active_region, edge_other_proj, edge_other_proj);
+
+		if ((ED_view3d_project_float_global(vso->active_region, edge_other_proj, edge_other_proj, V3D_PROJ_TEST_NOP) != V3D_PROJ_RET_SUCCESS) ||
+		    (ED_view3d_project_float_global(vso->active_region, start_vtx_proj, start_vtx_proj, V3D_PROJ_TEST_NOP) != V3D_PROJ_RET_SUCCESS))
+		{
+			/* not much we can do here */
+			return;
+		}
 
 		closest_to_line_v2(closest_2d, mval_float, start_vtx_proj, edge_other_proj);
 
@@ -470,7 +475,7 @@ static void vtx_slide_update(VertexSlideOp *vso, wmEvent *event)
 		if (edge_len <= 0.0f)
 			edge_len = VTX_SLIDE_SNAP_THRSH;
 
-		edge_len =  (len_v3v3(edge->v1->co, edge->v2->co) * VTX_SLIDE_SNAP_THRSH) / edge_len;
+		edge_len =  (BM_edge_calc_length(edge) * VTX_SLIDE_SNAP_THRSH) / edge_len;
 
 		vso->snap_threshold =  edge_len;