Here is a quick post with a small code change to randomly color material graph connectors in Unreal. Sometimes I can find it hard to navigate material node graphs in Unreal, particularly as the number of connections increases. For other node graphs types in Unreal the connector colors can be based on the type of data but in a material they are all displayed as white. Here is a little engine code hack I use locally that I find useful.

This is a continuation in a series of posts about writing BBC Basic programs for the @bbcmicrobot twitter bot. Previously we looked at making some simple effects using colour cycling and built up some programs to run on @bbcmicrobot. This time we will go in the other direction and break down an existing program to see how it works. Boing Ball The program we will look at is the one in this tweet.

These are some of the first few Shadertoy shaders I made. They are quite old now and some are simple compared to newer shaders on the site but I still think they are quite fun and interesting. Coffee and Tablet Shadertoy had video streaming quite early and I wanted to try displaying the video on a reflective screen. I thought a tablet would be quite an easy thing to model with Signed Distance Fields.

Retro I made a number of retro themed shaders on Shadertoy. I like how silly running something retro-looking on a GPU in a web browser is. Teletext This shader is simulating the old analogue TV Teletext system in a couple of shaders. The font is the same as the BBC Micro in Mode 7. Click play then click on the shader and type a page number. The gallery images on page 300 are by @horsenburger.

This is a continuation in a series of posts about writing BBC Basic programs for the @bbcmicrobot twitter bot. In the last post we looked at implementing effects on the BBC Micro using colour cycling with lines. This time we will look at similar effects but scrolling a grid. Setting up the Grid We will jump right into making a small program to draw vertical strips of different colours that we can animate with colour cycling.

This is a compilation of some of the optical illusions and perceptual effects I have made in Shadertoy. Warning - flashing images. Some of these shaders involve flashing images. If you are at risk of a seizure due to photosensitive epilepsy or other conditions, don’t click play, navigate away. Many of these effects are based on the fantastic work of Akiyoshi Kitaoka @AkiyoshiKitaoka. Click the Title of each shader to view the shader in Shadertoy.

In 2018 I did a presentation for Digital Dragons in Kraków on HDR Display in Call of Duty. This is a collection of the presentation materials and various related resources. YouTube Slides You can download the slides from the Activision Research Site. Shadertoy As I’m slightly obsessed with Shadertoy, I used Shadertoy for some of the diagrams in the presentation. I learned a lot from doing this and some of them may be useful as reference.

This is a continuation in a series of posts about writing BBC Basic programs for the @bbcmicrobot twitter bot. The first few programs I made for the BBC Micro Bot all used the same technique. A series of lines are draw in consecutive colours and then animated using colour cycling. To demonstrate this technique we will go through an example of writing a program to make a sideways scrolling parallax starfield.

This is some BBC BASIC information I’m putting in one place so I can find it easily. Let me know if you would like me to add any other information here. Documentation BBC Micro User Guide html | PDF BBC Micro Advanced User Guide Graphics Extension ROM User Guide | Download BASIC command summary Archives of old books BBC Micro Bot Editor BBC Micro bot editor BBC Micro bot editor - base2048 compressed PLOT Quick Reference Foreground colour PLOT commands.

Code Golf |>|||o OGolf is played for the lowest number of strokes. Code golfing is trying to make a program with as few characters as possible while still maintaining its functionality. I’ve been playing recently with the twitter bot @bbcmicrobot which runs a tweet sent to it as if it was a program for the BBC Micro (see my other blog post about this).