Saturday 22 December 2012

The Graphics

Well, where do you start ?

A bit of history. The motivation from this console , I think, comes from the hand held card games systems that you could buy - stand alone systems with LCD/LED displays that allowed you to play Blackjack or Poker against the computer. Those of us of a certain age remember the LCD/LED/VFD Handheld games which were the predecessors of things like Game and Watch. For a few years they were everywhere.

This system is a television version of that - it's designed to play Card games on a computer.

Looking at the image, you might think, well actually it doesn't look so bad. The font is a bit odd looking, but it's got colour, graphics characters and the graphics resolution is much better than things like the Studio2 - far blockier and monochrome or Channel F - blockier and a few colours.

What you don't realise until you actually read the datasheet is how limited this is. This is all it can do.

The screen is basically in two bits. The left bit (the BJ2 column) is a fairly ordinary memory mapped screen. It's only 6 characters wide by 12 high, and it only displays 64 characters (mostly ASCII) but it isn't that odd.

It's the right side that's wierd. This is actually 13 characters wide, but only six high. Each character space is double the height of the ones on the left, so the Jack of Diamonds in the picture is one character slot)

Each of those squares can display one of three things. A card (the character pairs on a black/red background), a solid white square occupying the same space, or one of the 64 characters.

But the 64 characters (e.g. the YOU LOSE and the numbers) can only appear in the bottom half of the square.  So the "YOU LOSE" message at the top of the screen has to go there - it is impossible to move it to the row above so it is aligned with "BJ2" - the system is physically incapable of it. Also, if you look at the numbers 14,15,17 they are also aligned with the bottom 'suit' character.

All this is always displayed on a green background (meant to be a gaming table I suppose), with only those colours (White, Red, Black). 

So it is, almost, impossible to do Pong (see last post). The left hand side isn't wide enough. The right hand side only offers 6 characters resolution - you could possibly do an incredibly blocky one with about half the vertical resolution of the Microvision but it'd just look silly.

Below is what Unisonic Football (American Football) would have looked like. This isn't a mock up by me - this is seriously suggested by GI as a possible cartridge release. (I don't know if anyone ever wrote it, I suspect not).  The six character vertical resolution means that there are no 'inbetween' positions in the graphics, so if you changed your line of attack it would jump up or down the screen a lot. (The reason for using the suit characters as graphics is that there aren't any others in the font that aren't alphanumeric or punctuation)


It's actually mad. You can see how you might design a system for TV based card games. But it's completely insane not to change it just a little bit so that the graphics could be used for other things, or the background colour would change. You'd just be adding a few logic gates to the circuitry, the additional cost in an LSI chip would be microscopic. Half of the bit combinations in RAM memory are used - so it displays a white solid block for every character code from 128 to 255, you could use this (say) to split every solid white block into 2x3 bits, so you could get a 38 x 18 block resolution. It wouldn't be hard.

I really would like to know whose idea this was, and what was going through their head when they finalised the design.

Note: Amended ; the RHS is 13 x 6 not 19 x 6 - the whole screen is 19 characters across.

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