Hop to the Top: Bunny's Revenge and IFF ILBM files

October 30, 2023

RobSmithDev released Hop to the Top: Bunny’s Revenge and posted a video about some of the production process. I did some of the graphics for the game, as well as writing the code for the intro. For the graphics, I ended up writing some custom code to automate some of the process, and it was an opportunity to learn about a popular Amiga image format.

My typical process for making art for retro systems is:

  • draw the piece in Krita and export as true color PNG
  • use GNU Image Manipulation Program to convert it to an indexed PNG, cleaning up the pixel art as needed in GIMP
  • use some tool somewhere to turn the indexed PNG into a retro machine friendly format

In the case of the Amiga, I’ve used ArtPRO on the Amiga in the past to convert PNG images to whatever format I needed. With all the art I was making, and potentially remaking, I needed a faster process. ArtPRO is good, but clicking buttons on retro machine software to convert images was going to be too slow.

I was also running into an issue with GIMP not preserving the index order of the color map I had created for the game. I think I had Remove Unused and Duplicate Colors from Colormap enabled which was messing up the color indexes, so be sure to disable that if you’re using a similar process.

Due to this, the resulting color map on the output images was all over the place, so I needed to fix that issue.

I had two approaches I could take:

  • automate the production of a sprite sheet encompassing all of the individual pieces of art and convert it once, fixing the palette issue.
  • convert each piece separately and load them as separate images, finding some other way to speed up the conversion & palette fix.

I chose the latter since I preferred separate image banks to start, over hard-wiring in sprite sheet locations, during initial development.

I decided to write a tool in Ruby that converts indexed color PNG images directly to IFF Interleaved Bitmap (ILBM) files, enforcing the order of the palette. It uses RMagick to load the image, and then implements IFF ILBM writer code to create the Amiga-ready files. It even supports run length encoding compression.

Here’s the source code. It drew heavily from the IFF ILBM reference found here, as well as from a lot of examining IFF ILBM files in hex editors. It only supports images up to 32 colors, so no Extra Half Brite or HAM images. If you end up using it, let me know!

Drawing YOUR REQUESTS on a Quantel Paintbox from the 90s! -- Full Stream

September 5, 2023

I uploaded the full Quantel Paintbox live stream, edited a bit to trim out some stream issues and to correct some audio issues. This was my first time not only recording a Paintbox, but also recording away from home, so there were plenty of issues to work around!

Below are the three pieces I produced during the stream. They came out as Targa files from the Paintbox that I converted to JPEG.

Thanks again to Adrian Wilson for providing me access to the Paintbox and giving me lots on instruction on how to use it. Hopefully I’ll get a chance to paint on it again!

Stream music by Nihilore.

A cartoon rat holding a Quantel RAT

A cartoon rat holding a Quantel RAT, an input device for the Paintbox.

A parody of a TV ad card for a show called Mission Bunpossible

A parody of a TV ad card for a show called Mission Bunpossible. This was a request by Rusty Ralston.

A digital painting of a one-eyed black cat, incorrectly titled as Henry

A drawing of Tyrel's cat Victor. I thought it was Henry. Oops! Sorry, Victor.

Drawing YOUR REQUESTS on a Quantel Paintbox!

August 31, 2023
Anthropomorphic rabbit sitting at Quantel Paintbox announcing that he will draw your requests on September 3rd

I’ve been given access to a V-Series Quantel Paintbox and I want to draw your requests on it! I’ll be on the machine for a few hours, streaming the art production on my PeerTube channel and talking with the Paintbox’s owner, Adrian Wilson, while I draw. Send in your characters, ref sheets, and requests, and I’ll do my best to honor those on this dedicated art machine from the 90s! Don’t make me just draw Topaz and the Amiga custom chip characters over and over, because I will if you don’t send anything in.

Don’t know what a Paintbox is? Watch my latest video to learn more!

Submission Instructions

If you want to submit a drawing request, use the email instructions on the About page to send me your request. Attach or link to any reference images I might need. You must email me your request! Requests made on Mastodon will cause me to point you at these instructions instead.

  • The deadline is Saturday, September 2 at 5pm! Any emails received after then won’t be part of this stream.
  • Requests must be safe for work! I am the sole decider of what that means, and I can work with you beforehand to make it SFW if needed.
  • One request per person, please!
  • Keep attached reference images smaller than 1 MB.
  • I’ll randomize the entries after I’ve sorted through them.
  • I may not get through every entry! If I don’t get to yours, I’ll email you and ask if you’d like me to feature it on a non-Paintbox art stream instead.
  • I’m not going to email you about anything else besides this art stream.
  • I’ll do my best to retrieve the final images off of the machine directly to send to you. If I can’t, you’ll have to settle for a screen capture. Hey, it’s free art from a custom computer from the 90s, whaddaya want?

Digital photo editing a decade before Photoshop? Meet the Quantel Paintbox

August 20, 2023

The popular shorthand for digital photo editing is based on the name of software developed in the 90s. However, that activity was already being done by users of a bespoke art computer developed by a British company in the early 80s, and the public could see the output of this machine everywhere. So why is digital photo manipulation not called “being Paintboxed”?

Thanks to DextersTechLab for actual Paintbox footage and technical assistance, Adrian Wilson for lots of feedback and resources!


Quantel Paintbox Resources



Moving from YouTube to PeerTube

August 20, 2023

I will no longer be publishing videos on YouTube, and will instead focus on publishing videos using PeerTube, the federated, community-driven video sharing platform. If you’ve never used PeerTube, it’s a lot like YouTube, except it respects you, your attention, and your data much more than Google does. This move fits in with trying to get ahead of what I’ve been experiencing on the Internet in the past few months:

  • Ad-driven corporate services eventually become unusable and hostile to their users (Twitter, Reddit). Given enough time, this will happen to YouTube (and some might say it already has!).
  • You have to play a lot of games on YouTube in order to gain and keep subscribers, and to let them know when new stuff is live (ring the bell, anyone?). These sorts of games will increase in complexity until YouTube just starts asking you to pay them to show your videos to others, while still showing ads on the videos, much like how other social media services have done for years.
  • Automated moderation is overly aggressive out of fear of driving off advertisers or viewers of the company being targeted by scammers. YouTube bots making a questionable assertion about a link in one of my videos pushed me over the line here.
  • I’ve heard enough horror stories about big name YouTubers being caught in an increasingly complex net of automated tooling that denies them access to their accounts or funding, and only the largest and most vocal users are able to get any sort of resolution. Meanwhile, that tooling makes scam accounts nearly impossible to stop, causing channel viewers to get scammed out of lots of money, or accounts, or whatever.
  • Being on the Fediverse for almost a year, interacting from one community-driven server and users to another, has been refreshing and feels like how the Internet felt in the 90s, except with much more modern tools around the communication and content delivery. Try sending something larger than a postage stamp-size video in anything higher than potato quality in the late 90s to someone over dialup! It’s not happening.

I’ve changed all of the video embeds over to MakerTube, the current host for my videos. The Industrious Rabbit has a channel, just like it would on YouTube. I may start other channels for other projects. Whatever is currently on YouTube is all that will be there from now on, and those are not guaranteed to stick around, either.

One downside is that PeerTube does not have account export/import/migration yet, so if my current host goes down, reuploading everything becomes a very long, manual process, and I can’t bring along users. If you like what you see here, follow me on Mastodon just in case the worst case scanerio happens. Of course, YouTube is even worse since it has no official export or migration tools, and makes it very tough to get in touch with all channel subscribers directly! I’ll likely make one final post over there to let interested subscribers know where I’m going.

Check out the other videos MakerTube users have uploaded, and if you like what you see, be sure to donate to your instance admins.

See you on PeerTube!

Amiga rasterbars are cool -- Meet the Copper, the hardware that helps make them happen

June 20, 2023

Rasterbars are a common special effect on early computer games and demos. The Commodore Amiga’s take on rasterbars are special due to the Copper, a special processor that synchronizes its activity to your monitor’s image rendering hardware.

Thanks to Tyrel (@tyrel@social.tyrel.dev)!