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Line Types in ArchiCAD
Written by László Nagy
Introduction
This explanation augments the description of symbol line types found in the ArchiCAD Reference Guide, specifically how special linetypes are created in ArchiCAD. The basic problem concerning special linetypes is whether you can define a certain pattern for them on the Floor Plan at the scale you are currently working or if you need to modify the scale or the size of the linetype stencil.
When the pattern is copied from the Floor Plan and then pasted into the Line Types setting dialog box it will appear there in real size (as opposed to being drawn at a scale on the Floor Plan). In that Dialog, the pasted pattern must fit into the available space and this limits what size patterns can be defined on the Floor Plan and the scale at which they can be defined.
- Checking desired size of pattern
- Finding scale range for pattern size
- Determining minimum and maximum sizes for pattern on Floor Plan at given scale
- How ArchiCAD pastes symbol line patterns into the Line Types Dialog
- Setting the number of decimal places for numeric fields in the Line Types dialog
- Go to the OptionsPreferencesWorking units... dialog box.
- In the Angle & Text Size Decimals in Dialog Boxes field, set the desired accuracy (3 or 4 decimals may be needed in some cases).
- Click 'OK' to confirm your changes. The 'Dash' and 'Gap' fields in the Line Types dialog will be displayed with the set decimal places.
With this process you can find out whether you will be able to create the symbol linetype from the pattern drawn at a particular size and scale on the Floor Plan. Let us consider that we have drawn the following 'standing brick' pattern on the Floor Plan. We would like to create a symbol line type by copying and pasting one segment of this pattern into the Line Types dialog and editing it there.
The variables mean the following:
| A | Width of symbol line type pattern |
| B | Height of symbol line type pattern |
| C | Gap between two pattern repetitions (note that the distance between the repetitions of the pattern equal A+C) |
In our example, this pattern is drawn at a scale of 1:100. In that case:
A_ [ or GLOB_SCALE] = 100 (current scale on the Floor Plan)
A = 65 mm
B = 250 mm
C = 10 mm.
There will be several other variables used in the Line Types Dialog. These are the following:
| Dash | - The value entered in the 'Dash' field of the Line Types Dialog |
| Gap | - The value entered in the 'Gap' field of the Line Types Dialog |
| b | - The height of the pattern in the Line Types Dialog |
The Line Types dialog can accommodate only a symbol linetype pattern of a certain maximum size: 107.95 mm (4.25 inches) in length and 25.4 mm (1 inch) in height (see above illustration). Also, there is a minimum size for the length for the symbol linetype pattern ('Dash' field) in the Line Types dialog, which is 1.00 mm.
This means that at each scale on the Floor Plan there are minimum and maximum sizes of how large or how small a pattern for a symbol linetype can be. It must be of a size that, when pasted into the Line Types dialog, will fit the available space. Then, when the symbol linetype is created and used on the Floor Plan it will appear as it was intended, and not in some other size or scale.
There are some constants to be used in the following calculations that will state the above-mentioned minimum and maximum values for the pattern size in the dialog:
| Dashmin | - minimum value for 'Dash' field (1.00 mm) |
| bmax | - maximum value for height of pattern (25.4 mm) |
| (Dash+Gap)max | - maximum value of 'Dash'+'Gap' (107.95 mm) |
Note: both 'Gap' and 'b' can have a minimum value of zero.
In our example:
Dash = A / A_ = 65 / 100 = 0.65 mm < Dashmin (1.00 mm) NOT OK!!!
At this scale, this size pattern cannot be done because the horizontal length of the pattern (A) is not large enough to be more than the minimum required in the Dialog. It would be arbitrarily increased by the program, and the resulting symbol linetype will not look as intended.
If the scale is changed to M 1:50 (A_=50) on the Floor Plan, then:
Dash = A / A_ = 65 / 100 = 1.30 mm >= Dashmin (1.00 mm) OK!!!
and
Gap = C / A_ = 10 / 50 = 0.20 mm (No minimum value required)OK!!!
and
b = B / A_ = 250 / 50 = 5.00 mm =< bmax (25.4 mm) OK!!!
So when the scale is changed to M 1:50, it can be seen that the pattern with the above values can be constructed.
Since a pattern can not be created - and of course can not be used - at all scales, you may wish to know the minimum and maximum scales at which you can still construct your desired symbol linetype pattern. Here's how to find it out. You just basically divide all values of the pattern (A, B, C) with their respective minimum/maximum in the Line Types dialog.
For the minimum scale, the higher of the following two values is the result:
A_min1 = B / bmax = 250 / 25.4 = 9.84
A_min2 = (A+C) / (Dash+Gap)max = (65+10) / 107.95 = 75 / 107.95 = 0.69
A_min = 9.84
For the maximum scale:
A_max = A / Dashmin = 65 / 1.00 = 65
So the scale range for this pattern is:
10 < A_ < 65
In metric: M 1:10 < scale < M 1:50
In Imperial: 1" = 1'-0" < scale < 3/16" = 1'-0"
(See conversion table at end)
From this you can see that our example could not be constructed at the scale of M 1:100 (since it is outside the range of M 1:10 - M 1:65) and M 1:50 is the largest scale possible. When the size of pattern is a given, you should use this method to find the appropriate Floor Plan scales at which the job can be done.
You may also want to do something at a given scale and want to calculate how small or large the pattern on the Floor Plan can be so as to be able to do it at that scale. With the first example (A_=100), here's how to go about it.
Amin = A_ x Dashmin = 100 x 1.00 = 100 mm
(A+C)max = A_ x (Dash+Gap)max = 100 x 107.95 = 10795 mm
Bmax = A_ x bmax = 100 x 25.4 = 2540 mm
B min = 0 (It can be zero)
From all this we can see that in the original example the 'A' value of the pattern on the Floor Plan was less than the desired minimum and this is why it could not be done.
When you paste the pattern from the Floor Plan into the Line Types dialog, ArchiCAD always tries to set the 'Dash' value to 40 mm and the 'Gap' value to 10 mm. There is usually no problem setting 'Gap' to 10 mm (unless 'Dash' is close to 107.95 mm long). However, the ratio between the width and height of the pattern can be such (e.g., in the case of a square: width would be set to 40 mm so height would also have to be set to 40 mm in the dialog) that at 40 mm 'Dash' value the height of the pattern would exceed bmax. In this case, the height of the pattern will be set to bmax (approx. 25.4 mm - may vary) and the 'Dash' value will be set to stay in ratio (in the case of a 'square' pattern: width and height would both be 25.4 mm).
Since the length of your pattern in most cases will not be 40 mm but some other value, you will need to change these numbers to the ones as calculated in previous sections or edit them graphically in the dialog.
Please note that these fields cannot be set to display feet & inches even if you are working in Imperial units otherwise.
Page last updated: Thursday, September 16, 2004
