Gradgrind Update

Monday, September 22, 2025

The Gradgrind palette editor for RISC OS has been updated, with a minor bug fix for hex display of colour values.

Download link: Gradgrind 0.91 beta (326k)

Work in progress: !Solar

Saturday, September 20, 2025
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We’ve had solar panels for nearly 14 years now, and the output has been reported daily on our site. The page is currently generated by a Python program running on a Raspberry Pi (a Pi400 at the moment), but I’ve been working on a version running under RISC OS, using BBC BASIC. Here are some samples of the output:

month2024-06-01.png
month2024-07-01.png
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It’s unfinished as yet, but work continues slowly…

Gradgrind

Thursday, April 3, 2025
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Gradgrind is a palette generator which takes particular care to create smooth blends between colours. The palettes are generated by curve-fitting rather than linear interpolation (using Catmull-Rom splines, if you’re interested), and can be created and saved as script files as well as edited interactively.

It can create greyscale palettes, which can be particularly useful when loaded into PhotoDesk and used as displacement maps or effect gradients. PhotoDesk can only generate linear blends, which can give visible artefacts, discontinuities and banding.

The program comes with full documentation and example gradient scripts.

Gradgrind is a RISC OS program. It will not run under any other OS.

This is a beta version, 0.90. It was written and developed under RISC OS 5.31. Prior versions of the OS may work; feedback is appreciated.

Download link: Gradgrind 0.90 beta (325k)