Slide mask spline segment to define it's curvature

This actually implements the idea used in Gimp which is grabbing
an arbitrary point on the spline and dragging it, ensuring spline
goes over this point. This is really useful way to tweak spline
curvature.

Currently only affects on a closest handle, meaning no weighting
on changes for both handles which are adjacent to the same segment
will happen just yet,

Another limitation is that currently such a slide is a big jumpy
when you start sliding. This is because projection is not used
to calculate u value because projection used to fail a lot for
me here and didn't find a nice solution for this yet. But this is
to be improved for sure!

1 files changed, 12 insertions, 0 deletions

diff --git a/source/blender/editors/mask/mask_intern.h b/source/blender/editors/mask/mask_intern.h
index 369d3aa1c6e..6899cf7e6f5 100644
--- a/source/blender/editors/mask/mask_intern.h
+++ b/source/blender/editors/mask/mask_intern.h
@@ -40,6 +40,17 @@ struct wmOperatorType;
 /* internal exports only */
 
 /* mask_add.c */
+bool ED_mask_find_nearest_diff_point(const struct bContext *C,
+                                     struct Mask *mask,
+                                     const float normal_co[2],
+                                     int threshold, bool feather,
+                                     struct MaskLayer **masklay_r,
+                                     struct MaskSpline **spline_r,
+                                     struct MaskSplinePoint **point_r,
+                                     float *u_r, float tangent[2],
+                                     const bool use_deform,
+                                     const bool use_project);
+
 void MASK_OT_add_vertex(struct wmOperatorType *ot);
 void MASK_OT_add_feather_vertex(struct wmOperatorType *ot);
 void MASK_OT_primitive_circle_add(struct wmOperatorType *ot);
@@ -55,6 +66,7 @@ void MASK_OT_layer_remove(struct wmOperatorType *ot);
 void MASK_OT_cyclic_toggle(struct wmOperatorType *ot);
 
 void MASK_OT_slide_point(struct wmOperatorType *ot);
+void MASK_OT_slide_spline_curvature(struct wmOperatorType *ot);
 
 void MASK_OT_delete(struct wmOperatorType *ot);