Commodore Amiga CD32

This came down from the loft a while back for a clean and functional check.

I thought I’d take a few pics of it up and running:

The Beast Itself.

 

Bios Screen

 

A battered up box

 

The precious contents

 

A part of the included paperwork

 

Two controllers. The eagle-eyed of you will notice that the D-Pads are different. This is because the original design on the right was due to be shipped out as it was, but feedback from testers slating the D-Pad design meant a last minute change of sticking a more directional pad on top of the original design. In the case of the right hand controller, this fell off and was lost some time ago.

 

More paperwork

 

The product labelling on the bottom of the unit.

 

Game time! Loading up Myth.

 

Myth mid game.

 

Amiga CD32 Rear ports. From left to right:

On-Off switch / Power Input / RF Tuner Output / S-Video Output / Composite Video Output / Left Audio RCA Output / Right Audio RCA Output.

Amiga CD32 Side ports, from left to right:

Controller 1 or mouse input port / Controller 2 or mouse 2 input port / Aux Input port.

 

Close up of the animal itself with top loading CD deck open.

 

Close up with lid closed.

Why is diagonal movement faster than straight movement in old arcade games / 8 bit computer games

I am talking bout real old skool games here, like early 80’s arcade stuff and old 8 bit computer games, but on a lot of them if you had a guy on the screen and you ran straight up, down, left or right you’d move slower than if you moved diagonally.

The issue sounds pretty odd but it’s easily answered and can be proved using Pythagoras Theorem.

If you push the left button, your guy on the screen moves 1 pixel to the left say, and if you push the up button your guy moves 1 pixel up the screen. Pretty straight forward yes.

Now if you push left and up at the same time then your guy moves up-left diagonally. This means he’s moved one pixel left and one pixel up in one move. The actual diagonal distance he’s travelled isn’t 1 pixel though, it’s actually just over 1.4 pixels, just like if you had a right angled triangle and the two shorter sides were 1 metre each then the hypotenuse would be just over 1.4 metres.

This means distance wise that every three straight the guy has travelled 3 pixels, but every three diagonal movements the guy has travelled over 4 pixels, hence why running diagonally gives you an advantage in old computer and arcade games, although usually the enemies had the same diagonal advantage too.

How to fix it? Well when you move diagonally, instead of shifting the guy one to the left and one up, shift him 0.7 to the left and 0.7 up and this will make the hypotenuse about 1. Of course ths screen itself can only display in whole pixels and will round up but as long as you don’t round up the actual x and y co-ordinates of the guy then he’ll skip a move every so often which slows him down to normal pace.

So why wasn’t this built into old arcade and computer games….Well there are three possible reasons:

1. It just wasn’t noticed to start with. (Unlikely)
2. It was noticed but people couldn’t be arsed to add the extra code to make it right.
3. Due to limited memory, there wasn’t enough space to add the additional code so programers just lived with it.