Modifying Line's endpoint via chook

[MRB]

I want to write a chook that would select a line and modify its endpoint in real time, 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.

Please let me know how I can do this. Thanks very much.

 

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Code so far

 

select_ent("Select a line", &oEntity, .....);

p_3d aStartPoint, aEndPoint;

curve_endpoints(&oEntity, aStartPoint, aEndPoint);

 

while(true)

{

p_3d oNewSelectedPoint;

point_proc ("Pick new position, Escape to finish", &Option, oNewSelectedPoint, &bSuccess);

 

//Make and store new line using above point

 

}

 

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

[Pete Rimkus from CNC Software Inc.]

//Make and store new line using above point

 

// erase the line

draw_ent(&oEntity, gr_back_color)

// modify one of its endpts (.e1 or .e2)

// with the new position

copy_p_3d(oEntity.u.li.e1, oNewSelectedPoint);

//save the modified line in the database

rewrite_ent(&oEntity);

// draw it

draw_ent(&oEntity, oEntity.color);

[Pete Rimkus from CNC Software Inc.]

Also note that there is now a Developer's Forum on this site. That would actually be the best place to ask questions like this.

 

HTH

[MRB]

Thanks for replying, Pete. It's good to know that there's a now a Developer's forum.

 

I should have pasted my entire code before. I did make a line using oNewSelectedPoint, but the point is not in the desired 3d space. Let's say I was to tweak the endpoint such that the new line is only 5 degrees from the original line. The point_proc() method is giving me a point which 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;

oint_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();

 

}

 

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

 

Should I be converting the new point to View or World coordinates, or is there a different method that needs to be used. Is there a way to do this dynamically?

 

Thanks again Pete.

[MRB]

I'm moving this question the Developer's forum