Working on 'et' (my escape-time program) this morning.

I added presets from 1x1 through 8x8, selectable by keypress. It already did supersampling but you had to enter 3 numbers in a modal dialog.

The calculations of the array used for progressive image rendering were annoyingly slow, so I'm now caching them on disk using the xdg-basedir and vector-mmap packages (et is written in ). I also need the directory and filepath packages for this part.

The arrays get quite big, almost 700MB total for all supersampling sizes with a base resolution of 1024x576 pixels (it takes up 6 bytes per pixel). Changing the base resolution size means recalculating and storing another set of arrays. Cache will bloat!

So I'm thinking there might be a better procedural way to do what the arrays do, which is style interlacing (coarse pixels getting gradually finer in a multipass rendering) with the pixels in each pass ordered so that the center gets rendered first and it spreads out towards the edges.

So in short I need a cheap function from (ImageWidth, ImageHeight, PixelIndex) to (PixelX, PixelY, PixelWidth, PixelHeight), because using anything other than to increment PixelIndex is much too slow in Haskell.

Added a new feature to et-gtk: quick image saving. The time of program launch is stored, and pressing 's' saves an image with this timestamp and a sequence number in the filename. Uses the 'xdg-userdirs' (to find "~/Pictures" regardless of language) and 'time' packages (to get the time and format it).

Eventually the PNG files will contain metadata (formula, coordinates, etc) that can be reloaded into the et GTK GUI, and I want to add a batch mode to the CLI renderer so I can point it at a bunch of such PNGS with options like "re-render all of these at higher resolution".

Even later I want to add an 'r' shortcut to add to a render queue, so I don't need to launch the CLI renderer manually.


I re-enabled "ignore isolated glitches" for non-progressive rendering (as used in the CLI renderer, but not the GTK GUI). This speeds up high resolution perturbation rendering at the cost of inaccuracy (hopefully invisible after downscaling).

Theoretical worst case is 1/4 of pixels being wrong, but that is highly unlikely in practice.

Sign in to participate in the conversation

Welcome to, an instance for discussions around cultural freedom, experimental, new media art, net and computational culture, and things like that. This is part of a family of services that include mailing lists, group chat, and XMPP.