Make knotholders for LPE items finally work; each effect can now overload the addKnotHolderHandles() method to add handles which control its parameters.

There is now also a virtual onKnotUngrabbed() method for each knotholder entity which can be used to do cleanup tasks (for LPE parameters it currently writes the value to SVG, although this should probably happen automatically)

(bzr r5855)

1 files changed, 6 insertions, 0 deletions

diff --git a/src/knot-holder-entity.h b/src/knot-holder-entity.h
index 5c273fe29..f0862c874 100644
--- a/src/knot-holder-entity.h
+++ b/src/knot-holder-entity.h
@@ -43,11 +43,17 @@ public:
                         SPKnotModeType mode = SP_KNOT_MODE_XOR,
                         guint32 color = 0xffffff00);
 
+    /* derived classes like PointParam for LPEs use this, e.g., to indicate that we must not call
+       delete on their pointer when a knotholder is destroyed */
+    virtual bool isLPEParam() { return false; }
+
     /* the get/set/click handlers are virtual functions; each handler class for a knot
        should be derived from KnotHolderEntity and override these functions */
     virtual void knot_set(NR::Point const &p, NR::Point const &origin, guint state) = 0;
     virtual NR::Point knot_get() = 0;
     virtual void knot_click(guint /*state*/) {}
+    virtual void onKnotUngrabbed() {} // this is called 'manually' from KnotHolder; would it be
+                                      // more efficient to establish another signal connection?
 
     void update_knot();