topic Re: Dynamic input of dynamic block in Dynamic Blocks Forum

Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 08:18:05 GMT

Attached is a simple dynamic block that stretches both ends from one grip.

When stretching, the dynamic input is as shown on the attached image.

Is it possible to have the dynamic input as indicated in red?

Thanks.

Re: Dynamic input of dynamic block

h_s_walker — Wed, 21 Feb 2024 09:50:46 GMT

Is the red distance going to be consistent all the time. If so why not move the arrow grips the back the distance it needs to be? Just like I've done in the attached drawing

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 09:51:21 GMT

Depending on what you finally need there are several ways.

One of them is attached.

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 10:21:37 GMT

Maybe I wasn't very clear in my request...

Initially I'll stretch by the right hand grip to a new overall length

Then what I need is to grab the left hand grip, stretch to the left and type in however much I need to stretch by.

eg. I type in 0.05 and the block stretches by 0.05 at both ends.

Currently I need to type in "original length + stretch amount".

Hopefully that makes sense (I'm pretty much a beginner when it comes to dynamic blocks).

Thanks.

Re: Dynamic input of dynamic block

h_s_walker — Wed, 21 Feb 2024 10:59:18 GMT

What version of AutoCAD do you have? It may be a better idea to use constraints. Linear parameters can not start with a 0 length, they have to be a distance which is not 0

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 11:27:26 GMT

Test the attached block WCILL - pa1.

Re: Dynamic input of dynamic block

h_s_walker — Wed, 21 Feb 2024 11:40:24 GMT

@j.palmeL29YX That was my first thought

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 12:09:16 GMT

WCILL - pa1 only seems to have one grip for overall length and when I try and open it in the Block Editor I get ; error: bad argument type: lentityp nil...

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 12:43:03 GMT

@dlbsurveysuk wrote:

WCILL - pa1 only seems to have one grip for overall length .

That is what you asked for in post #4 ("I'll stretch by the right hand grip to a new overall length").

"Then what I need is to grab the left hand grip, stretch to the left and type in however much I need to stretch by."

(view in My Videos)

What/where is my misunderstanding?

when I try and open it in the Block Editor I get ; error:

Try it again, here are no problems

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 13:02:56 GMT

Hi, thanks for your response.

I meant that there is only the overall length grip. There is no grip on the left for stretching.

Attached image shows block.

Could there be some AutoCad setting/variable that I need to change?

Thanks.

PS Your video shows exactly what I want.

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 13:16:34 GMT

Here a new upload.

HTH

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 13:35:31 GMT

This time I get errors (see attached). After recover it is the same problem as before.

PS I am running full AutoCad 2022

Maybe a quick description of how you did it, and I could try and figure out constructing the block myself?

Re: Dynamic input of dynamic block

h_s_walker — Wed, 21 Feb 2024 13:35:43 GMT

Say no to the errors then copy and paste the block into a new totally blank drawing. Do you still get the errors?

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 13:44:01 GMT

@dlbsurveysuk wrote:

I get errors

Ok I can (must 😞 ) confirm that. To open this block in ACAD 2022.1.3 shows the same problem here too.
I'll try to find how to avoid that - it will need a while ...

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 13:46:03 GMT

If I say no to the errors then copy paste into a blank drawing there is still no grip on the left and I get ; error: bad argument type: lentityp nil in the block editor as before.

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 13:46:37 GMT

OK thanks for your time.

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 13:57:40 GMT

After recovering the file it works also in ACAD 2022.

To do that:

- Open a new file

- command RECOVER

- select the new uploaded file

You will get a message that 2 objects were erased (I don't know which objects, they have nothing to do with our block definition). => Now the block works well (here, I hope for you too).

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 14:06:52 GMT

OK. All working now. Thanks very much for your time.

Re: Dynamic input of dynamic block

dlbsurveysuk — Wed, 21 Feb 2024 17:58:11 GMT

OK, so I've just been looking at the block to see how it was constructed for future reference.

Just to confirm - everything is the same as the original block I supplied apart from, you have given the linear parameter 2 the same point as start and end, so that it has a zero start length, and describes the stretch distance only?

So you can have a zero start length for a linear parameter?

Re: Dynamic input of dynamic block

j.palmeL29YX — Wed, 21 Feb 2024 19:10:42 GMT

@dlbsurveysuk wrote:

Just to confirm ... you have given the linear parameter 2 the same point as start and end, so that it has a zero start length?

So you can have a zero start length for a linear parameter?

No and no. As @h_s_walker correctly wrote, a dynamic parameter can never have length = 0.

I tricked a little - if you zoom close to the parameter (and set the precision of the units to 8 decimal places), you will see that the start and end points are 0.000001 units apart. That's why I wrote above, test the block (whether it meets your practical needs and whether you can live with such a small inaccuracy).

Sorry for the small cheating, but first I wanted to understand how you want the block to work. Perhaps there are other ways (e.g. using constraints) to achieve your requests. I did not yet try ...