Postscript: Write graphics to a postscript file

OpenGL graphics does not support graphics output to a printer. This command allows creating a postscript file. Multiple images (up to 6) may be arranged on one single page, the number must be given; the images are automatically positioned and have equal size if the number is even.

After specifying the file title and some parameters, the postscript file is opened and the postscript header is written by pressing the button „Open file“. Optionally some own postscript commands can be copied from a given file on top of the postscript file to be created. After opening, the graphics window is hidden and graphics into the file is done using the MAKROS graphics commands as usual. Graphic is superimposed until a new image is selected with button “New image”, For example structure plot, plot of node Ids and plot of graphic text are done with different commands. For graphic text the text groups that should be plotted must be set active before. Text height and color is taken from the chosen font.

Button „Close file“ must be used to close the postscript file; with button „Printer“ it can immediately be sent to a printer. If more than one image are arranged on a page, the active image must be finished and the next image opened by using button „Next image“.

For postscript the window coordinates are scaled, if some lines or surfaces are only partly visible in the graphics window these lines and surfaces are not plotted at all, because their coordinates are not available.

If the used printer does not support color, grayscale should be used for surface plots. Grayscales can be defined using command „Post color“. If a black background is used for graphics in the graphics window grayscales are automatically adjusted for postscript. Color index 0 is used for white and color index 1 is used for black.

With some kinds of graphics representation it may be better to make a hardcopy from the graphics window using HyperSnap and print this copy, for example column plot douse no hidden line calculation.

After invoking the command, the shown dialog box pops up with following options:

Postscript file

The actual title of the postscript file is shown in the dialog, default is projectname.ps. Using button “New file title” a new file can be selected in a file selection dialog. The selected file will get the extension .ps.

Insert Postscript file

If the option “Insert” is set, the postscript commands contained in the give file will be copied on the top of the file to be created. Using button “New file title”, a new file can be selected in a file selection dialog.

Page size, number of images

DIN A4: Page size is set to DIN A4 upright format.

DIN A4 landscape format: Page size is set to DIN A4 90° rotated; all images are also rotated by 90°.

Width / height: Width and height of page size can be given in cm in the input field.

Number of images: The number of images to be positioned on one page can be given in the input field (£ 6).

Frame, border width, etc.

Plot frame: If this option is set, each image will be framed.

Border width: In the input field, the width of the borders on the left, right, bottom and top of the page can be given.

Plot axis: With this option set axis are plotted to show the current view.

Plot project title: If this option is set, the project title is plotted on the left of the top border.

Plot date and time: If this option is set, the date and time of file creation are plotted on the right of the top border.

Hidden surface plot

For the plot of surfaces it is important to know how the surfaces are overlapping each other. It can be chosen between following options:

No overlapping: This option is fastest, the surfaces are continuously plotted.

Plot sorted by z-values: The surfaces are plotted corresponding to their z-position, surfaces with lower z-positions at first.

Do hidden surface calculations: This option is most time consuming, a hidden surface calculation is done by software. The used algorithm assumes that there are no intersections between surfaces. Pixel coordinates of the actual graphic are used for hidden surface calculation. To avoid rounding errors the graphic window should be as big as possible if the structure has lots of small elements.

Surface normals

The plot of surfaces will be less time consuming, if some surfaces can be separated by the direction of the normal vectors. For example this is the case, if a closed or a solid structure is plotted where all surfaces on the backside can be separated.

Following options can be selected:

Take into account: The normal vectors of the surfaces is checked

Only positive: All surfaces with normals oriented to the back are separated.

Only negative: All surfaces with normals oriented to the front are separated.

Open file

Pressing this button, a new postscript file with the given title is opened and a new page is initialized. After that, graphics can be written to this file.

Next image

If more than one images are positioned on one page, this button has to be used to initialize the next image, the number of this image has to be given in the input field. The number of the active image is shown in the dialog.

Close file

Pressing this button the postscript file is closed and can be sent to the printer.

Switch off / on

This button can be used to interrupt the output to the postscript file, for example to change and test the view for the next image. When interrupting output to the file, the graphics window is set visible and following graphics will be shown in the graphics window. With the same button, which is now labeled “Switch on” graphics output is newly directed to the postscript file and the graphics window is hidden again.

Printer

Using this button, a newly created postscript file can immediately be sent to the printer. If the file is still opened it will be closed. For printing, there must exist a file “maka_interface.ini” in the folder of the executable, with the following line:

Printer: “printer command”

For “printer command” the text enclosed in quotation marks must be given to send a file to the printer, where a % character is the placeholder for the file title, for example

Printer: “lpr printername %”

Printer: “copy % COM2”

The given text will then be executed as a system command. The file “maka_interface.ini” is also used for special interfaces (see chapter “Interfaces to FE-Programs“)