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.

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 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).

Colour Cycling In the last post we looked at some simple graphics commands on the BBC Micro. Typically using the graphics commands on a BBC Micro running at actual speed would be too slow to allow complex animations to run fast enough. In this post we will examine how to use colour cycling to provide cheap animation. We looked at how the command VDU 19 can be used to change the palette of colours.

Posts Fun with BBC Micro Bot BBC BASIC Colour Cycling BBC BASIC Code Golfing Tips Colour Cycling Effects with Lines Colour Cycling Effects with Grids BBC Boing Ball BBC Micro Reference @bbcmicrobot I’ve been having a lot of nostalgic fun with @bbcmicrobot lately. BBC Micro Bot is a Twitter bot written by @DominicPajak. The official page is here: https://www.8bitkick.cc/bbc-micro-bot.html If a tweet sent to the bot starts with a line number, it will run the tweet in the cloud as if it was a program typed into an 8 bit BBC Micro.