Gridder

Gridder can generate grids in image form according to the specified settings, either as brand-new images or drawing on existing ones. Grids can have various shapes, such as square or hexagonal, and are highly configurable.

Suggestions and appreciation are welcome! Feel free to email me or open an issue on Gitlab.

Usage

Gridder can draw either on an empty background or on an existing image.

To use an empty background, run gridder.py <width> <height> <grid size>, where:

• <width> is the width of the image in pixels.
• <height> is the height of the image in pixels.
• <grid size> is the interval, in pixels, at which each line of the grid will be generated. This effectively corresponds to the side of each square of the grid.

To draw on an existing image, run gridder.py --file <file path> <grid size>, where:

• <file path> is the path to the image on which Gridder will paint a grid.
• <grid size> is as described above.

Note that the --file (or -f) option must be the first argument if specified.

The result of the above will be a file named grid.png in the same directory. If used, the existing image will not be modified.

Options

The following optional arguments (or their aliases) can be provided:

• --gridtype, alias: -gt specifies the shape of the grid. Possible options:
  • square squares (default),
  • vhex vertical hexes (flat side on top and bottom),
  • hhex horizontal hexes (flat side on left and right),
  • vline vertical lines,
  • hline horizontal lines.
• --linewidth, alias: -lw specifies the line width of the elements of the grid. Default: 1.
• --gridcol <colour>, alias: -grc specifies a for the grid, as the name of a colour or a string format recognised by Pillow, such as hex values like #000000.
• --bgcol <colour>, alias: -bgc specifies a for the background, as the name of a colour or a string format recognised by Pillow, such as hex values like #000000. For a transparent background, omit this argument or specify transparent. NOTE: This cannot be used when drawing on an existing image using -f.
• --padding <size>, alias -p specifies a padding of pixels around the grid, i.e. a padding between the borders of the image and the actual grid.
• --paddingtop <size>, ..right, ..bottom, ..left, alias: -pt, -pr, -pb, -pl specify each a padding of specific to the indicated side. Each can be used separately, and they will take priority over the generic --padding option above.
• --destination, alias -d specifies the file name of the finished image. Do not include extension, as it will always be .png automatically. The default file name is grid.png.

Units

By default, all size arguments, <width>, <height>, <grid size> and all applicable optional parameters use pixels, but other units are also allowed, namely:

• cm,
• mm,
• in.

These units all assume a resolution on 300dpi as customary for printing.

For example, a grid created by running gridder.py 12cm 12cm 1in will be 1417x1417 pixels and have 300-pixels wide squares.

Known issues

• Due to rounding errors, hex grids may have some unwanted bold edges.