How to rescale model

I have created model with format: decimal, meters, 0,000m.
I have created a terrain model. Then I have found that the map #1 which I used to generate terrain model is wrong scale. I inserted new map (#2) into the model, changed size to fit the original map (#1). Now I have this: 600m on the map #2 is equal to 740,253. Is it possible to rescale whole model so that I will have 600x600m square equal to 600m? The map and the square with scale are in separate groups. I am using SU 8.


Use Tape Measure tool

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Thank you, this seems to be easy with 2D model. But one problem.

What if I need to rescale 3D terrain, where the countours are made with 3m heights (3m gaps between each other on y axis). I need to rescale only the width and depth (x,z axis), not to modify the y axis. I think I can use Scale, but the Scale tool is not exact… Maybe this is not big deal in this model because the original map / terrain is in small scale and the newer map is much higher resolution. But I am curious.

It’s exact, just type the dimension and unit.

You could use Tape Measure tool + Scale tool

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It’s not quite clear to me how to rescale the model. I have to calculate the dimensions manually because I don’t know the correct result measures. H

how to calculate them?

On the image I have selected the things I will scale. The second not selected is the map I am using for orientation. This is the goal size.

You see the selected image has a white space on the right.

My measures:
x1: 1999,608 (good size)
x2: 1243,4 (wrong size)
ratio: 1,608177578
xMax2: 1667,754
xMax2 correct: 2682,044588
There xMax2 correct is the size after rescaled x axis.
But I need to calculate this on z axis too. This is crazy!

Look carefully at the tutorial from my first post.
You have a known dimension in the picture - 250 m. You will use it to scale your plan.

But if you have the correct plan in vector format, after importing it into SketchUp you should no longer need to scale it.

Tape tool will rescale the y axis. Am I right?

Tape Measure tool will scale model as a whole.

In SketchUp:

  • X axis is red
  • Y axis is green
  • Z axis is blue

And that is the problem. When I want to rescale the terrain, I need to rescale x and z only. Notice that I have selected map to be rescaled and terrain with the map on once try.

Scale tool works differently. It is not so comfort.

So I think I only can to calculate manually. I need to use the result ratio to calculate z size. It may cause some desort maybe on some levely of high precision model.

I already showed you in the second animated GIF how to scale the model correctly on X and Y (+temp Z).

With Tape Measure tool you’ll scale the whole model and determine the correct length and width (based on a known dimension, in your case - 250 m), and with Scale tool you will then resize for the Z axis, to have the desired distance between the level curves.

The plan I used contained mistakes. This is why I need to correct.

Did you see the image I attached with dimension arrows?

You see that I need to calculate the size. I don’t know the result measure, I need to calculate it.

The only thing you have to calculate is the total height. You use the 250 m that you know and you will have the correct length and width of the plane (the horizontal plane XY).

Use first Tape Measure tool (whole model), and then Scale tool only for Z axis.

That is wrong scale.

250 is incorrect? What is incorrect? You need to know one correct length to set the scale of anything. Do you know the scale you want to be at?

There is one map which is hidden. I didn’t want to confuse. The hidden map is correct and more precision than this one. The image which is not selected is already resized to the correct map. Both images are low precision and no one contains correct scale. The correct scale is on the hidden map.

It looks like whatever I do there is risk of deformation/ disortion.

Use one dimension you know is correct.

In this example I used the length of the orange square as a known dimension.

Apply what I already explained.

First I tried rescale using scale tool red,green. But I did not got the correct dimensions which I typed in. Changed to cm to achieve better precision.

but typing this takes so much time and result is invalid.

So now I am going to use scale green and scale red (2x scaling). The measures are already calculated so should be fine.

Ok, I hit problem. I will paste two images here.

Why the hell when I drag right, the box will drop down like this:

It seems that either while I am writing the value or while I switch to Excel, it will drop down. So it will rescale y axis… Hell…

Exactly, I cannot enter the value because the box will drop down.

So I have found that Fredo Tool - FredoScale is much better then the Scale.

FredoScale is the best…
I just pasted the new dimensions from the table.

I have created component from the corrected map. I called it <scale>. It is correct size/scale now. There is also the map with the original scale which is 100% correct. Seems like 250m on the wrong scale map is equal to 320m on the corrected map.

Now I insert it into terrain model, which is wrong size. This wrong model contains map and the terrain. It’s wrapped in “rescale” group. Now I have used FredoScale to correct the size of “rescale” group. I did not used units to fix exactly, but the height is OK. The top right corner with orange color is at 780m ASL.

map terrain with colors - rescale.skp (12.9 MB)