topic Re: LASTANGLE for custom objects in ObjectARX Forum

LASTANGLE for custom objects

thierry_prince — Wed, 23 Mar 2016 14:35:54 GMT

Hi,

We have a custom object that is similar to a polyline and, while in its construction command (and also when the command is finished), we need to update the LASTPOINT and the LASTANGLE system variables.

No problem with the LASPOINT variable, but the LASTANGLE variable is read-only. (Why ?)

An example for this need is to launch a transparent command while in the object construction command to calculate the next point with the last one and the orientation of the last segment.

Any suggestion ?

(Other than to draw a new line with 'acedCommandS' API function to force the update of the variable, and deleting the line after that.)

Thanks.

Thierry

Re: LASTANGLE for custom objects

tbrammer — Thu, 24 Mar 2016 14:10:01 GMT

I agree that using acedCommandS(L"_line") is a bad idea.

Have you tried to create a new AcDbLine and add it to the modelspace using ARX? You can make the line invisible before you add it to the DB.

This shouldn't disturb your command flow.

Re: LASTANGLE for custom objects

thierry_prince — Thu, 24 Mar 2016 14:34:25 GMT

Hi,

Thanks for your answer, but I can't believe that creating a new AcDbLine and adding it to the model space will update the LASTANGLE value.

I'll try it but with very few hope...

Cheers,

Thierry

Re: LASTANGLE for custom objects

Anonymous — Thu, 24 Mar 2016 16:12:18 GMT

maybe, to get last entity in any of the spaces (model, paper) that it is a curve (AcDbCurve) and calculate the angle.

Re: LASTANGLE for custom objects

thierry_prince — Thu, 24 Mar 2016 16:35:36 GMT

Sorry LE3, but I don't need to calculate the angle : I would set it in the LASTANGLE system variable 🙂

Re: LASTANGLE for custom objects

tbrammer — Thu, 24 Mar 2016 17:31:26 GMT

I just tried it myself. You're right. It doesn't work.

Neither by appending a new AcDbLine to the modelspace nor using acdbEntMake(resbuf);

Sorry. No more ideas right now 😞

Re: LASTANGLE for custom objects

owenwengerd — Thu, 24 Mar 2016 21:49:46 GMT

I think the correct way is to use a jig for creating your entity. As far as I know, this should set both LASTPOINT and LASTANGLE (LASTANGLE I guess only if acquireAngle() is called). Note that this behavior may be influenced by the kDontUpdateLastPoint flag.

Re: LASTANGLE for custom objects

thierry_prince — Fri, 25 Mar 2016 09:18:39 GMT

Hi Owen,

Thanks for your answer. I think we are not so far to an acceptable solution.

Effectively, when using a Jig to get a point, the LASTPOINT system variable can be updated or not, regarding of the use of the kDontUpdateLastPoint flag.

But if we consider that our object is similar to a polyline, the AcEdJig::acquireAngle() can't be used to input a vertex, because it returns only an angle.

We need that every acquired point update the LASPOINT variable and, starting from the second point, that every new point also update the LASTANGLE variable.

So writen, it seems to be very simple... 🙂

Re: LASTANGLE for custom objects

owenwengerd — Fri, 25 Mar 2016 20:12:12 GMT

@thierry_prince wrote:

We need that every acquired point update the LASPOINT variable and, starting from the second point, that every new point also update the LASTANGLE variable.

Have you tested whether acquirePoint() with a basepoint updates LASTANGLE?

Re: LASTANGLE for custom objects

thierry_prince — Mon, 28 Mar 2016 08:33:10 GMT

Hi Owen,

Yes I do that.

I also read carefully the ObjectArx documentation and nowhere is writen about LASTANGLE.

Even the API function acquireAngle() doesn't update the LASTANGLE variable. It updates only LASTPOINT !

I try to update many time the LASTPOINT variable for the case it will update the LASTANGLE automaticly. But not.

Cheers