Original Article Date: June 5, 2002
Yet another article by Anthony Cox. This piece was originally written for Red Box Design's CAD Manual and explores the contents of their customized plot driver files. A handy-dandy reference guide to bookmark and learn from!
Yet another article by Anthony Cox. This piece was originally written for Red Box Design's CAD Manual and explores the contents of their customized plot driver files. A handy-dandy reference guide to bookmark and learn from!The following is a breakdown of values that are used in our office and a description of why we use them.num_pens=1Tells the plotter to print everything using one pen.num_pens=63Allows us to assign one pen to each level of information (in V7). We can then tailor each pen to each level.num_pens=255Is the maximum available and allows us to mix colours for colour images.How we actually control the thickness and colour is explained later.
change_pen=LEVELThe office standard which means that MicroStation will use a different pen for each level of information. This comes in handy when we want to change the colour of everything on individual levels other options include COLOUR or BOTH.end_plot=ejectRolls the page forward.rotate=NONEThis is controlled at print time by the orientation of the sheet.model=HPGL2This actually means nothing, but tries to associate a plotter family with a particular driver. This is proved in the next line which tells us which "language" is to be used.driver=hpgl2The MDL application used to produce the HPGL2 output and the office standard.autocenterAutomatically centre plot on page.
The next line is used to control the output of the information. A separate driver file is used for each different situation that exists in the office. You must only have one per driver.default_outFile/auto_overwrite = "\\redbox01\hpdj488ca"Automatically sends the information without using the operating system using the "address" of the device. Although the operating system is not used, it is aware of the existence of the file and is listed as a "Remote Download Document" in the Windows dialog box. default_extension = 'PLT'The method we use to create a "file" of the information. MicroStation then searches its variable list for a preferred location for the plot file. We set the variable MS_PLTFILES in our PCF and is tied to each project. Using this method we get a warning if the file exists. For office procedural reasons, this must never be allowed to happen as the plot file relates directly to issues and there must never be two versions of a drawing with the same file name.default_extension/auto_incExt="000"Not used in the office, is used when multiple copies of a file is created without the file name changing. For example plotfile.dgn produces plotfile.000, 001, 002 and so forth. Warning - if you substitute the "000" for PLT the program produces undesirable extensions such as: PLU, PLV, PLW default_outFile/auto_overwrite = "lpt1"Not used in the office, but suitable for completely "stand alone" computers with the plotter connected directly to the back of the computer. In Pre-V7 days the program automatically asked for a file name. If you typed LPT1 is then redirected to the Local Port 1.
The next line allows us to individually tailor how each pen behaves. The office practice for typical production drawings is to force everything to black, except for level 34 (finish lines to reflected ceilings), level 38 (finish lines for floors) and level 63 (should never be plotted). Where we have set the number of pens to 63, our office standard, we use the following:pen(38)=(38)/rgb=(160,160,160)Sets Pen 38 to colour grey, we have already set level=pen above.pen(34)=(34)/rgb=(120,120,120)Also set to grey but slightly darkerpen(1-33)=(1-33)/rgb=(0,0,0)Forces these pens to print blackpen(35-37)=(35-37)/rgb=(0,0,0)Forces these pens to print blackpen(39-62)=(39-62)/rgb=(0,0,0)Forces these pens to print blackpen(63)=(63)/rgb=(200,0,0)Forces this to red to indicate to the manager level 63 is plotted in error.As a result of the use of shading, we can order the way information is set to the plotter. In the following pentable everything in level 34 and 38 is processed first. That way black outlines and text is not obscured. How we achieve this is beyond the scope of this technical note. pentable=m:\CAD\cad_standards\issue\check.tbl
Metric size records:There is a lot of confusion about how the size record works, and although our office system may not be the best, it works quite well. There is just one wee problem and that is our plotfiles are created for a particular sized width of paper.General MicroStation Rules:
General Hewlett Packard Rules:
How MicroStation figures out the scale of the plot:Typically, a fence or a view is used to indicate the desired plot area. The office standard is to snap to markers on the standard sheet file. MicroStation calculates the size of the rectangle and compares it with the "PLOTTABLE" area of the sheet. It does this differently in two situations.If the task is passed to the operating system, it establishes the actual size from the operating system. This may not be a whole number, nor will it be the same between different brands of printers. For instance the printable size of an A3 paper from a HP Laserjet is different than the Epsom 3000.The more predictable way of managing this sizing is to tell the program through the plot driver file. The actual size can be found from consulting the printer documentation. You will notice that the size of the plottable area is different if the A1 is landscape or Portrait. (The HP Specifications list an A1 Landscape as being 831x560, but in portrait it is 807x584.)MicroStation then compares the fenced size against the actual plot size. It assumes you are going to try to plot AS MUCH as you can, so indicates it is using up %100 of available area. It then indicates how much it had to manipulate the fence to get it to "fit" into the available plotable area. The office standard is to keep the A1 sheet at full size and then scale down the reference files to suit (this also helps in other areas). Because we have already established that the plotable area for an A1 sheet of paper on a A0 roll (which is A1 wide) is 831x560, our printing marks are set to that. It compares one to the other and in the second box tells us it has had to manipulate the size by a factor of one to get it to fit.It compares this value with the size record (also 831x560). It allows 17mm at the start of the plot regardless, starts drawing our information, of which the last piece of information is 560mm away and then rolls forward another 17mm to give a total depth of 17+560+17=584.We centre our plot, start the plot 5mm in from the right hand edge of the paper, but only have a plot window of 831mm. The standard roll is 841mm wide, so our right margin becomes 5mm.The only down side is the you cannot have anything printed closer than 15mm to the top and bottom margin so we use 20mm which does tend to look a bit wide.If an offset is introduced using the MicroStation record, it is added to the overall plot size by the HP Plotter, which again screws up the sizing hence we set the offset at 0. Bentley has erroneously set this at 7mm which is completely wrong.Note: There is a general practice of using 610mm (US Imperial) rolls of paper in offices, this is because users create an A1 sheet sized border and fence the extremities. This size then gets sent to the plotter- where it then ADDS additional margins.For additional information about setting up your plot sizes, please refer to the following: / Plotting to Scalesize=(386,287)/num=0/off=(0,0)/name=a3_landsize=(1155,831)/num=0/off=(0,0)/name=a0_Landsize=(560,410)/num=0/off=(0,0)/name=a2_landsize=(560,831)/num=0/off=(0,0)/name=a1_portsize=(831,560)/num=0/off=(0,0)/name=a1_landNote that we use the same dimension for landscape and portrait, this is because the plot comes out in landscape orientation regardless of what the orientation is set to. This is why we had Rotate=None at the start of the plot driver file. resolution(MM)=(0.025,0.025)Metric resolution of the plotter (often called Plotter Resolution Units)and is standard for HP Plotters. It tells us the thinnest line the plotter can produce is 0.025mm in thickness.stroke_tolerance=4.5As set by Bentleyweight_strokes=(4,7,10,14,20,28,40,56,80,112,45,160,320,452,640)The weight strokes command implies there is only a single black pen. HPGL2 assumes you are using actual pens, one black one and three coloured ones that it mixes to get the different shades of colour. We dictate thickness based on this command, and colour based on the previous "pen" command. The individual numbers correlate to the pens 0, 1, 2, 3, 4, etc. So to draw a line with MicroStation Weight 0, it uses its logical pen of 0.025mm and uses it 4 times which equals .01mm. The proportional change between pens is the same as the changes between draughting pens.style(1) = (0,7000000)/nohardware; style = invisablestyle(2) =70,42)/nohardware ; style = med dashstyle(3) = (168,56)/nohardware; style = long dashstyle(4) = (112,42,28,42)/nohardware; style = dot-dashstyle(5) = (56,56)/nohardware; style = short dashstyle(6) = (84,28,28,28,28,28)/nohardware; style = dash-dot-dotstyle(7) = (112,28,56,28)/nohardware; style = long dash - short dashWe use the style command to dictate the look of our custom pens and we use the nohardware switch to ensure that the plotter does not impose its own settings. You will notice that style 1 has a different number than that supplied by Bentley. We use this as our invisible line. Style 1 has always traditionally been difficult to see on a hard copy, so we altered it to produce a dot that is 7000000 units away. We set a unit to be 0.025mm so style 1 pen is a dotted line that in essence never gets drawn. The number of styles relates to the number of pen styles available in MicroStation excluding Custom Line Styles.The remainder of the plot driver file is unaltered since it doesn't affect our office standards.
AskInga Article #108