Dynamically modifying line's endpoint via chook

[MRB]

I'm trying to write a chook that would select a line and modify its endpoint dynamically, or by sketching/selecting a point in graphics space. This functionality would be similar to Mastercam's 'Edit->Modify NURBS' functionality.

 

I'm searching for chook functions that would help me do this. Currently, I'm using point_proc(), and it doesn't sketch a point in desired 3d space.

The point_proc() method gives a point that is lying in a plane normal to the selected original line.

 

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//Select the line

 

select_ent("Select a line to modify", &oEntity, &oDBEntity, oPtSelect, dTParam, ALIVE_BIT, ALL_ENTITIES_MASK, select_color, &bSuccess);

 

// Get the curve endpoints

p_3d aStartPoint, aEndPoint;

curve_endpoints(&oEntity, aStartPoint, aEndPoint);

 

 

// Ask for new point

while(true)

{

 

ent oLineVector;

DB_LIST_ENT_PTR d_ptr;

 

char Option;

p_3d oNewSelectedPoint;

Point_proc ("Select new position, Escape to finish", &Option, oNewSelectedPoint, &bSuccess);

 

if(!bSuccess) break;

 

oLineVector.id = L_ID;

vec_3d(aStartPoint[X], aStartPoint[Y], aStartPoint[Z], oLineVector.u.li.e1);

 

vec_3d(oNewSelectedPoint[X], oNewSelectedPoint[Y], oNewSelectedPoint[Z], oLineVector.u.li.e2);

 

store_ent(&oLineVector, &d_ptr, 0, main_color, main_level, main_attrib, &bSuccess);

 

repaint_graphics();

 

}

 

-----------------------------------------

 

Thanks in advance for any help.

[bryan314]

I'm guessing unless you're selecting your point off another entity when you select a point off 'in space' Mastercam will interpret your point to be in a plane defined by the Z construction Level.

 

Also as a side note; in select_ent above you can force it too select only lines by changing ALL_ENTITIES_MASK to L_ID. That is, unless you're trying to get splines and stuff too, then my bad. sorry.