How to scale rotate dwg data using four reference points?

[ssharma_panindia]

Hi guys please suggest how can we scale rotate the data using four reference point?

[imadHabash]

Hi and Welcome to AutoCAD Forum,

Would you please show us your CAD case, You may get more than answer.

[Valentin-WSP]

@ssharma_panindia ,

This may help - see the second video in this link:

• Rotate and Scale Objects by Reference | Autodesk

[Pointdump]

Hi @ssharma_panindia,
Welcome to the Autodesk Forums.
More details please. Screen shots or even post your drawing.
Dave

[cadffm]

Hi,

4 in a 3(D) world!?

Do you mean 2 ppints? 2 source and two target point = 4 ?

Use command ALIGN and skip the 3rd point

[autoid374ceb4990]

Sounds like you are looking for a least squares type fit where you have a set of control points and a set of reference points to be "fitted" into the control points.  Many years ago I was in the land surveying business and I wrote such a routine, but it was just for points, not entities like LINEs, PLINEs, etc.  Do you have 4 control points and 4 reference points?  How far different are the control and reference points?  Do you want to adjust more than AutoCAD POINTs?

[ssharma_panindia]

Hello sir,
Greetings of the day.
Thanks for your quick response.
My issue is , i have cadstral map in DWG file and ECW file of that location.
I want to georeference the DWG file according to ECW file.

DWG file contains line,polygon,and point.

Now I am doing georef using align,scale and rotate command which takes two
source point and two destination point.
But data are more scattered so I want if we can have a tool or command
which uses four souce point and four destination point. Which help our cad
data set georeference properly and conveniently on ECW image.

Looking forward to hearing from you.

Regards
Sachin Sharma

[Pointdump]

Hi Sachin,
Hoping you have Map 3D or Civil 3D. The Map command ADERSHEET will do what you want.
Dave

[ssharma_panindia]

Thanks for your suggestion for adersheet. we are using adersheet but the data shape is changing, so if it is possible to align the block data align with 4 source and 4 destination point  please suggest. so we need rotate, scale the data in block so that shape of the data will not change like align command.

in algin command it takes two source point and two destination point but we want align the block data with four source point and four destination point.

[ssharma_panindia]

Dear Sir,

What is possible block data align with 4 source and 4 destination point  please suggest. so we need rotate, scale the data in block so that shape of the data will not change like align command.

in algin command it takes two source point and two destination point but we want align the block data with four source point and four destination point.

[ssharma_panindia]

Thanks for your suggestion. I Mean this What is possible to align the block data align with 4 source and 4 destination point  please suggest. so we need rotate, scale the data in block so that shape of the data will not change like align command.

in algin command it takes two source point and two destination point but we want align the block data with four source point and four destination point.

[Pointdump]

Sachin,
"cadstral map in DWG file and ECW file"
"we are using adersheet but the data shape is changing"
Please zip everything together and post what you have.
Dave

[ssharma_panindia]

Dear Sir,

Due to security concern i am unable to send dwg and ecw.

I just want to know can we do align using 4 source point to 4 destination point.

if you could provide lisp file for this concern then it will help me.

[autoid374ceb4990]

What is the relationship of the 4 points in the DWG file to the 4 points in  the ECW file?  In other words if you draw a polyline through the 4 DWG points and another polyline through the 4 ECW files, could you put the two polylines in a DWG file and post them here?

Are the "block data" you keep referring to actual AutoCAD BLOCKs?

[richard_387]

To use four reference points is to admit that the geometry in the two sets of data are not equal.

Distortion of the data set is by using Align improperly in 3D as the data will be tilted.

You should use Align with two points, each with zero Z, to align in 2D and then move the data to a best fit in the Z.