Posts

Line drawing 3 - Code Example

Using the Amiga blitter to do line drawing is not so easy. There are a lot of moving parts to take care of before that first line hits the screen.

Line drawing 2 - Using the Blitter

The Bresenham line drawing algorithm, was usually implemented in software, but that all changed with the Amiga. The Amiga introduced line drawing in hardware, and if you stick around I’ll show you how it works.

Line drawing 1 - Bresenham's Algorithm

I have for a long time wanted to write something about the Amiga’s support for line drawing. It’s an area of the Amiga, that’s not so well described out there. This makes it a bit of a challenge, and I lost count on how many times I tried to poke at this stuff.

Amiga Machine Code Detour - Reverse Engineering

History has shown time and again, a demand for reverse engineering of programs. The reasons are many, some innocent and some not. Either way, it’s an interesting skill to have, that will make you a better programmer.

Horizontal Sine Shifting

One of the classic demo effects, of all time, is horizontal shifting using a sine wave. This effect is easy to code on the Amiga, using Copper instructions to deliver timed updates to the custom chip registers.

The Starfield Effect

In this post we are going to take a look at the starfield effect - one of the classic graphic effects of all time. If you want to learn how a starfield is programmed on the Amiga, using simple pixel drawing and double buffering and a bunch of fixed-point arithmetic - you’ve come to the right place.

Make Your Own Graphic Assets

The Amiga Machine Code Course, contains many examples using graphics, but we have never created our own graphics. In this post we are going to make up for it, by showing how to create custom graphics and store them in a format that works with the program examples.

Amiga Machine Code Letter XII - Vertical Scaling Using the Copper

The Amiga demo scene produced a wide range of clever effects, written in assembly language. Enjoyed by many, and understood by few, they pushed the envelope of what was thought possible on a home computer system.

Amiga Machine Code Letter XII - HAM

The Amiga had one of the most photorealistic image modes in the late 80’ties, which could display a massive 4096 colors at the same time - something never seen before in a home computer system.

Amiga Machine Code Letter XI - Fizzle Fade

In this post we are going to look at a neat technique to do fast multiplication. The technique is described in detail in the last chapter of Letter XI, and involves doing bitshifting instead of naive multiplication.