Printing high resolution images

PowerShape uses two methods for printing windows: one for views containing only wireframe and the other for shaded images.

If the view contains only wireframe, printing is done at the full resolution of the printer.

If the view contains colour shading, OpenGL is used to render it into a bitmap and the bitmap is sent to the printer. Making a bitmap at the full resolution of the printer can be impractical as it could be large. Instead, PowerShape makes a bitmap which has the same aspect ratio as the printer but is limited in resolution so that its size doesn't exceed a limit.

The limit is set by a resource in the following file:

...\PowerShapexxxxx\sys\misc\powershape.con

The relevant section of code for setting the size is:

#

# Printing colour shading.

#

# This resource controls the size (in Mb) of the intermediate bitmap

# which is used to print colour shaded images. Increasing its value

# increases the printed resolution at the cost of temporary memory

# usage and file size. Decreasing it reduces print resolution and

# memory and file size requirements. 15Mb has been found to be a good

# compromise on plain A4 paper in a typical inkjet printer.

# print_opengl_bitmap_size: 15

To set the size

  1. Open the resource file:

    ...\PowerShapexxxxx\sys\misc\powershape.con

  2. Locate the relevant section of code (shown above)
  3. Remove the # from the command line so that it reads
    print_opengl_bitmap_size: 15
  4. Save the resource file.

You can experiment with larger values for this resource. Each pixel of the image requires 3 bytes, so if you want a print resolution of X by Y dots, then set this resource to:

X * Y * 3 / 1,000,000