GP: New Cutter, Constraints and Segment selection

This commit groups a set of new tools that were tested in grease pencil object branch before moving to master. We decide to do all the development in a separated branch because it could break master during days or weeks before the new tools were ready to deploy.

The commit includes:

- New Cutter tool to trim strokes and help cleaning up drawings.

- New set of constraints and guides to draw different types of shapes. All the credits for this development goes to Charlie Jolly (@charlie), thanks for your help!

- Segment selection mode to select strokes between intersections.

- New operator to change strokes cap mode.

- New option to display only keyframed frames. This option is very important when fill strokes with color.

- Multiple small fixes and tweaks.

Thanks to @pepeland and @mendio for their ideas, tests, reviews and support.

Note: Still pending the final icons for Cutter in Toolbar and Segment Selection in Topbar. @billreynish could help us here?

1 files changed, 13 insertions, 0 deletions

diff --git a/source/blender/editors/include/ED_gpencil.h b/source/blender/editors/include/ED_gpencil.h
index c231d0dc355..808e8461471 100644
--- a/source/blender/editors/include/ED_gpencil.h
+++ b/source/blender/editors/include/ED_gpencil.h
@@ -259,4 +259,17 @@ void ED_gpencil_tpoint_to_point(struct ARegion *ar, float origin[3], const struc
 void ED_gpencil_calc_stroke_uv(struct Object *ob, struct bGPDstroke *gps);
 void ED_gpencil_update_color_uv(struct Main *bmain, struct Material *mat);
 
+/* extend selection to stroke intersections
+ * returns:
+ * 0 - No hit
+ * 1 - Hit in point A
+ * 2 - Hit in point B
+ * 3 - Hit in point A and B
+*/
+int ED_gpencil_select_stroke_segment(
+	struct bGPDlayer *gpl,
+	struct bGPDstroke *gps, struct bGPDspoint *pt,
+	bool select, bool insert, const float scale,
+	float r_hita[3], float r_hitb[3]);
+
 #endif /*  __ED_GPENCIL_H__ */