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README.md

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+# griddle
+
+`griddle` is a program for practicing drawing using the [Grid Technique](https://www.art-is-fun.com/grid-method).
+It takes an input image and uses [ImageMagick](https://imagemagick.org) to automatically draw a grid (of specified dimensions) over it.
+
+## Installation
+`griddle` is a shell script; you can copy it to somewhere in your `$PATH` or just clone the repository and execute it.
+
+## Usage
+The CLI interface for `griddle` is `griddle <inputfile> <number_of_columns> <number_of_rows> <outputfile>`.
+This is the number of **columns** and **rows**, not the number of separators.
+For example, specifying "2" columns will result in **one** line splitting the image vertically.
+Border lines around the edge of the image are always generated.
+
+It supports any input and output file formats that ImageMagick supports.
+The input and output files don't need to be the same format; you can input a PNG and output a JPEG, for example.
+
+## Planned Features
+- Generate an additional output image (or PDF?) containing a blank copy of just the generated grid which can be printed out, to save the effort of manually recreating the grid on your drawing paper.
+- Improve the CLI interface with `--options` to remove the arbitrary ordering of `<number_of_columns>` and `<number_of_rows>`.
+- Make border lines optional.
+- Allow the user to adjust the color and transparency of grid lines.
+- Add a default output filename (something like `<inputfilename>_grid.<inputextension>`) if no output filename is explicitly given.