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steveFitz

340 post(s)
#16-Apr-14 00:55

Hi,

When I export labels to dxf the appear very large in AutoCad.

This may be a symptom of my lack of AutoCad experience or maybe there is something that can be done to prepare the label component for export so the labels are a suitable scale on export.

Any help (CAD or Manifold) would be great!

Steve

oisink
370 post(s)
#16-Apr-14 09:11

The labels are sized in ACAD according to their size in Manifold, but there is a weird scale factor. By trial and error worked out that height = point size * 3.78?! (This is in British National Grid).

In ACAD, you cannot use the SCALE command in ACAD, as this will move the labels towards your base point. Using QuickSelect to select all the labels and changing their height in the PROPERTIES dialog (CTRL+1) is only useful if the labels are the same size.

The alternative is to size the labels in Manifold first to get the right size in ACAD. You may need to work out your own scale factor by sizing some labels in Manifold first, exporting them and measuring their height in ACAD and Manifold to find your scale factor.

Urghh, its all very messy. I would like an option in Manifold to size labels by height and not by point size.

Regards

Oisin

adamw


10,447 post(s)
#16-Apr-14 09:27

I would like an option in Manifold to size labels by height and not by point size.

Could you elaborate on that a bit? What units should height be expressed in?

A point is 1/72 of an inch.

oisink
370 post(s)
#16-Apr-14 13:16

Hi Adam

I didn't know 1 point = 1/72 of an inch!

Does that mean if I make a label have point size 72 and render it at 1:1000, its scaled height on plan should be 1000 inches? It doesn't seem that's what I get! No doubt I'm misunderstanding something.

Oisin

adamw


10,447 post(s)
#16-Apr-14 13:44

I take it you meant 1000:1, not 1:1000. If you set label font size to 72 points, then fix the render zoom for the labels at 1:1 (View - Properties, Zooms, Render zoom), and zoom to 1:1 as well (use the combo in the Navigation toolbar, for example), the label should be roughly 1 physical inch high, accounting for vertical space used by the font above and below the letters. If you zoom further to 1000:1, the label will be 1000 inches high. If you zoom back to 1:1000, it will be 0.001 inches high. This will carry over to printing, too.

oisink
370 post(s)
#16-Apr-14 15:57

Thanks Adam

I think we're at cross-purposes. Yes, its about an inch high allowing for vertical space. So rendered at 1:1000, and printed at 1:1000 a 72 point label's size on printed paper will about an inch, representing a scaled height of 1000 inches.

Returning to Steve's query. the render zoom has no effect on what is exported in DXF format. So Steve has to size his labels on the basis of 1 point = 1/72" before export to get them at the desired size.

My point was that I would like to specify the actual height of the labels in map units (not paper units). i.e. if I say a label should be 2m high, at 1:500 this would appear as 4mm height, as printed. I hope this makes sense. Of course, knowing what I know now I can reverse engineer this. It would be nice however to be able to specify label height directly in this manner.

Regards

Oisin

adamw


10,447 post(s)
#16-Apr-14 16:11

Yes, this makes sense. Thanks for the explanation.

There has to be a way to honor render zoom when exporting labels to DXF (same for drawings). I will investigate that and file a suggestion or two into the wishlist.

Thanks again.

JonS1 post(s)
#21-Apr-14 10:52

There is the "scaletext" command in CAD.

This has the option of scaling by a factor or setting all to one height.

Jon

valimai
14 post(s)
#21-Apr-14 12:24

I'm new in CAD. Where to find scaletest command?

steveFitz

340 post(s)
#22-Apr-14 01:11

Oisink & adamw,

Thanks for that. Makes sense. I'll think about a script to work out the maths part perhaps and help choose font sizes equivalent to metric scaled units.

JonS - thanks for that too.

Valimai - enter the command scaletext in the AutoCad command line at the bottom (or where ever your AutoCad command line is).

Regards,

Steve

oisink
370 post(s)
#22-Apr-14 18:58

My algebra is rusty, but let's give it a go....

Remembering each Point = 1/72 of an inch

Let

  • Ha = Height of labels as represented by the map at given scale (in metres!)
  • Hp = Height of labels on the paper / screen (in millimetres)
  • P = Point Size
  • Sr = Render Scale expressed, for example, as 1000 for 1:1000 (remember, in the absence of explicitly stated Render Scale, Sr = Sm)
  • Sm = Map Scale expressed, for example, as 1000 for 1:1000

Now Isolating Ha and Hm

  • Ha = P/72 * 25.4/1000 * Sr
  • Hm = P/72 * 25.4 * Sr/Sm

or isolating P

  • P= 72000/25.4 * Ha/Sr
  • P = 72/25.4 * Hm * Sm/Sr

Is this correct?

Oisin

adamw


10,447 post(s)
#23-Apr-14 07:30

Looks correct, yes (I take it, Hm should be Hp).

oisink
370 post(s)
#23-Apr-14 08:27

Yes, Hm should be Hp.

Thanks O

steveFitz

340 post(s)
#24-Apr-14 00:02

Oisink,

Thanks for doing the heavy lifting.

I'll have a crack at some kind of script when I can work out exactly what I want it to do (!?).

I'll post back then...

Steve

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