trev2005

Typing those C&VG programs into my TI was my programming education. Not that the games were well coded, more that fixing the typos and bugs was an excellent start in learning to program. I don't recall a single listing from that magazine being correct. Happy times!

PM sent - hope I'm not too late!

I'd give the advantage to the TI sprite system against Atari's PMG in straightforward use for the types of game being released when they competed against each other. The PMG are lower resolution,
narrower, more expensive memory-wise in normal use and there are fewer of them. However, I do think that PMG has advantages in some areas - the larger areas of colour when scaled up can act as an underlay to the playfield graphics and soft-sprites in front of them, it's easy to create large vertical overlays such as cockpit struts for a flight sim, screen area borders that you don't need to redraw when scrolling etc.

The real power comes when you combine PMG with the Display List and in particular the Display List Interrupt. This lets you change anything about the graphics - mode, colours, character set, scrolling offsets, with scan-line accuracy and without having to count the scan lines in a kernel as you would need to in the 2600. If you wish, and I think some early 2600 conversions did, you could write to the player register directly in a DLI or kernel without memory access and change the player hardware bytes, colours or enable/disable them on each scanline but the computer hardware was engineered to make this unnecessary.

For PMG players using DLIs you can shift a single player around, changing position and/or colour of the player stripe on different mode lines down the screen so that it bahaves like a number of sprites. If you consider something like Miner 2049er then it's likely that in some if not most levels all of the enemies are made from a single player stripe chopped around and colour-changed. For demo purposes, you could split the player on each mode line and combine the missiles into a 5th player to give you 5 players x 24 player splits = 120 apparent sprites if you only want horizontal movement. Not very useful or practical I know put possible.