Amiga Vs Neo-Geo (scaling and rotation)

[Digiman]

It has 4x the bandwidth of OCS the bandwidth and supports 8bit in all modes. Thats more than a bug fix. ECS on the other hand was underwhelming.

Except using an 8 bitplane method for 256 colour screens pretty much used any new bandwidth increase. 8 bitplanes and no byte per pixel mode clearly shows AGA was a quick fix as the speed was affected badly due to this omission. Byte per pixel VGA was 4-5 years older than AGA too.

[bbond007]

Except using an 8 bitplane method for 256 colour screens pretty much used any new bandwidth increase. 8 bitplanes and no byte per pixel mode clearly shows AGA was a quick fix as the speed was affected badly due to this omission. Byte per pixel VGA was 4-5 years older than AGA too.

I totally agree. From a programming standpoint one pixel = one byte just is so much simpler. I can't believe somebody in the AGA process did not think... now that we support 8BPP 256 color mode and a pixel is now one byte, why don't we just... Accessing the AGA's 256 color registers was rather funky as well.

I'm a software guy though

Perhaps that is why the Ranger only supported up to 7bit mode, because when you get to 8 the design does not make sense.

I believe the C= 65 had chunky pixel mode...

[darkcoder]

Except using an 8 bitplane method for 256 colour screens pretty much used any new bandwidth increase. 8 bitplanes and no byte per pixel mode clearly shows AGA was a quick fix as the speed was affected badly due to this omission. Byte per pixel VGA was 4-5 years older than AGA too.

Your first sentence is unfair. 8 bitplanes saturates the bandwidth in Super Hi-res.
In lo-res (the relevant resolution for games):
  OCS/ECS 32 colors leaves 3/8 bandwidth free
  OCS/ECS 64 colors leaves 1/4 bandwidth free
  AGA 256 colors leaves 3/4 bandwidth free

In other words, OCS/ECS had enough bandwidth for lo-res 256 colors (but not enough RAM and the 68k would have been totally locked). AGA had 4x the OCS bandwidth so it can handle 256 colors lo res leaving more than enough free bandwidth for the 14Mhz 020 of the A1200

[Hattig]

You have to consider the effect of heavy blits (or soft-blits) don't you? These could require multiple reads and a write that also had to use the same bandwidth. There was a reason that games like Alien Breed AGA used 128 colours instead of 256...

[darkcoder]

You have to consider the effect of heavy blits (or soft-blits) don't you? These could require multiple reads and a write that also had to use the same bandwidth. There was a reason that games like Alien Breed AGA used 128 colours instead of 256...

@Hattig: not sure if your comment was in reply to mine. I don't understand precisely what you mean, but I guess you are adding a reason why to arrange a 256 color display, chunky-pixel is faster than 8 bitplanes. I totally agree.

This does not change the fact that the sentence "Except using an 8 bitplane method for 256 colour screens pretty much used any new bandwidth increase." written by Digiman is wrong.

Although AGA was not a stellar improvement, in my opinion to call it a "bugfix" of OCS is a great exaggeration

[Khephren]

did the neo-geo feature many 3d or strategy games? if not, it's a lame duck from my perspective ;P