Working with Linetypes

Linetypes in TBC can be created from imported CAD files or they can be created using AutoCAD ® .LIN files. Inside a .LIN file the linetypes are defined using a format similar to that shown below.

*RPS-WATER_LINE,Water Line ----W----W----W----W----W----W–
A,.2,-.1,[“W”,STANDARD,S=.04,U=0.0,X=-0.02,Y=-.02],-.1

The first line is the definition of the line name (RPS-WATER_LINE) along with a description (Water Line) and then an indication of what that line will look like ----W----W----W----W----W----W–

The second line defines the Pen Up and Pen Down sequences ad the Text to embed “W” and the Text Style to use (STANDARD) and then the Size of Text (S=0.04) and then the overrides to the text plcement (an X offset (back and forth along the line) and a Y offset (Right and left of the line) and then the final Pen Up before starting the repeat pattern - in the example shown the text will be placed in between two .1 gaps in the line (-.1) and is moved toward the start of the repeat pattern by -0.02 which makes the text more central in the gap between the dashes.

A Linetype definition can embed text or symbol characters derived from a TBC Text Style (which defines the font / character set to use) or from a shape file (.SHP) that defines the symbols / shapes.

So for example if you want to embed the characters HW in a dashed line, you define the characters to use HW and then you define the Text Style or Shape File from which those characters will be created. This means that in order to use e.g. a Text Style that is defined in the .lin file that TBC has to have the Text Style of the same name defined in the project / project template that you are using and that if that refers to a font file e.g. a True Type Font (.TTF) that the TTF Font File has to be installed on your computers Windows Operating System.

I have been working with a company that uses Comic Sans MS font for everything in their drawings, and they even have the linetypes defined using that font - so to recreate their styles on my computer / TBC Setup I had to do the following

  • Use Google Search to find a source of the Comic Sans MS and Comic Sans MS Bold True Type fonts. Download them and install them in my Windows setup.
  • In TBC Project Template - create a Text Style called COMIC that uses the Text Font Comic Sans MS and another Text Style that uses the Text Font Comic Sans MS Bold.
  • Edit the .LIN file to create their linetypes with repeat patterns and text styles so that they work well in Feet and or metric from a repeat pattern perspective.
  • Load the .LIN file linetypes into my Project Template and test them to make sure that they look good and work well.

Note:
The Text Style that you define in TBC should be used only for linestyles. The Text Height should be set to 0.00 - the scaling of the text will then come from the line type definition. If you enter a text height into the text style used in linetypes then the height of the text style when other than 0 overrides that defined in the line type. The text height is used only when the linetypes are imported into the project or project template. Changing the text height in the text style after the linetypes are imported has no effect on lines drawn in the project.

The line repeat patterns defined in the linetytpe and the text characters or symbol characters defined in the linetype will scale with changes in Plan View Scale made via Project Settings - View - Plan View, Plot Scale. i.e. changing the Plot Scale from 50 to 25 Scale will halve the height of the text or symbol characters and will halve the line type pen up and pen down patterns.

A repeat pattern of e.g. 0.4 pen down followed by 0.2 pen up will have a repeat length as determined by TBC of 0.4-0.2-0.4 i.e. 1.0 so that both ends of the line will have a pen down. The length of the line segment being drawn with the linetype will then dictate the number of repeat patterns and the variations in length of the repeat patterns. i.e. for the above 0.4 - 0.2 - 0.4 sequence at 50 scale the repeat lengths are 50’ and multiples of 30’. so a line segment 40’ in length will have reduced pen down - pen up lengths and a line segment 60’ in length will have longer pen down - pen up lengths (based on the half length of the pattern (being 25’) so at 74.99’ the Pen Down and Pen Up length will be at its longest and at 75.01 it will be at its shortest etc. In this way the same pattern will be deployed on varying length line segments. on line segments that have multiples of repeats there would be an initial repeat of 50 followed by subsequent repeats of 30’. This means that a long repeat pattern will have more variances than a shorter repeat pattern.

Note also that many AutoCAD ® .LIN files are defined in Metric Units vs English / Imperial / USFT units. The patterns are typically defined in Sheet Units (mm or inches) and this can make some difference in the way that lines are presented with their linestyles. For example a linetype pattern defined in Metric with the following Das - Gap - Dash sequence in mm

*DASHED,Dashed __ __ __ __ __ __ __ __ __ __ __ __ __ _
A,.5,-.25

Has a 0.5mm at scale pen down and a 0.25mm pen up at scale. So at a scale of 1000 this would be a pen down of 0.5m (0.5mm x 1000) and a pen up of 0.25m (250mm) and an initial repeat pattern length of 1.25mm (1.25m) followed by 0.75mm (0.75m)

If you read in the same linetype file into TBC and select English Sheet Units, then the repeat pattern will be quite different because now the repeat is 0.5" and 0.25" so at 50 scale this equates to 25" and 12.5" so many times larger than its intended use in meters. If you read the same file into a USFT project as meter sheet units then the 0.5mm and 0.25mm is converted into inches and will generate similar looking linestyles to those in metric, however the repeat patterns will never be round intervals of feet on the ground - having said that the scaling of the repeat patterns to segment length makes the segment lengths non uniform anyway so this is likely a moot point.

Linetype File loading in TBC

A .LIN linetype file is unitless. The values that define a linetype pattern of pen up and pen down sequences are defined in SHEET units. If you are working in Feet then a Sheet Unit is 1 inch. If you are working in Metric then a Sheet Unit is 1mm. Note that when working in Feet your scales are normally 1"=50’ (which is the equivalent of 1:600 in metric terminology. in Metric your scales are normally 1:1000 or 1:500 (1mm = 500mm).

What I am seeing however is that LIN files that are unitless tend to use values like 0.5 for a Pen Down. This is 0.5" in feet which at 50 scale would be 25’ on the ground (converted to meters this is ~7.62m).
This is 0.5mm in Metric which at 500 scale would be 250mm i.e. ~8".
As described above - if you import a .lin file in Metric Sheet units into a USFT project, you will get similar linetypes to those that you would see from the same file in a metric project at a similar scale.

What is clear to me from the above is that a .LIN file defined for a metric user if used for a Foot project will give vastly different results.

To make it worse when you import a .LIN file you can select whether it is in Metric or Feet units - so if you are working in a feet project and you select a metric file and say it is defined in metric then it will be converted into Feet from metric i.e. a 0.5mm pen down gets converted into a foot value using the metric to foot conversion factor - the result is a linetype that has a tiny repeat pattern.

So at RPS we have built a US Foot Linetype library available to our All Tools subscribers that works well in TBC and exports well to AutoCAD to help you get this right.

Many AutoCAD Linetype definitions reference a specific font file e.g. ltypeshp.shx. You need to find the .SHX file that is referenced by the linetype file and place it in the folder that TBC to find additional font files which is at this location

C:\Program Files\Trimble\Trimble Business Center

Here is a third party link to a download location for SHX files that you may need.
Click Here

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