So what type of games are available for the 7800? Mostly arcade ports, and very good ones at that. The system is backwards compatible with the 2600 and is in fact in my opinion 'the atari console system' to own.
The system could output 320x200x256 with 25 colors and 100 sprites and that shows. The sound is lacking in quality though as it uses the same limited sound chip as the 2600.
Too late, too mediocre - especially in Europe.
But whatever, I only wanted to point out that the only real standout feature of the graphics hardware compared to the earlier 5200 model is the sprite section.
Not counting the sprites the 7800 graphics are *not* similar to VGA - neither in resolution nor in color depth.
You can clearly see that most games - the ones with many colors - only use a horizontal resolution of 160 pixels - which is also the resolution of choice with the older Atari hardware and also often used by the C64 for example.
While 320 horizontal pixels were indeed possible this - like with the 8-bit Atari computers - restricted the amount of colors dramatically: Only two brightnesses without resorting to programming tricks like display interrupts (quite well known at the time, though) which had other restrictions.
So, while it is possible to get more colors with 320 horizontal pixels the "rules" are pretty much strangulating the programmer and they weren't really employed by commercial software.
VGA on the other hand - especially the mode that is most often associated with it: 320x200x256 - is more of a clean engineer's approach to computer graphics and it shows. This mode has four distinct advantages:
- A resolution of 320x200 square pixels. No wider than tall pixels like with a resolution of 160x200 which means circles are round...
- An unrestricted color palette of 256 colors - all of them controlled by color registers from an RGB palette of 3 x 2^6 = 2^18 = 262,144 colors. Changing a register meant changing all pixels using that color in an instant.
- A continuous frame buffer of 64.000 bytes (320x200x1 byte). No weird addressing scheme with holes (Apple II), non line addresses
- This mode like practically all PC graphics modes (and therefore the software using it) runs with 60 Hz wherever in the world you are - so US games software had no problems in Europe and vice-versa. A thing that really plagued games on earlier machines.
Yes, VGA had no 100 sprites and no raster interrupts (AFAIK) but for a good part they weren't needed at all. First of all there were "enough" colors, especially for handdrawn graphics and secondly as every pixel consists of a single byte there's only a limited amount of computation needed to manipulate the frame buffer (for example for moving objects). Now throw in a fast CPU (which had to manipulate the graphics at the time) and you have a good, powerful system. All in all it was equally good for displaying presentations, digitized photos and game graphics.
The 7800 is still far from that, even though it may be sufficient for TV sets of the period and, of course, was clearly more advanced than the 5200.
The system could output 320x200x256 with 25 colors and 100 sprites and that shows. The sound is lacking in quality though as it uses the same limited sound chip as the 2600.
Too late, too mediocre - especially in Europe.
But whatever, I only wanted to point out that the only real standout feature of the graphics hardware compared to the earlier 5200 model is the sprite section.
Not counting the sprites the 7800 graphics are *not* similar to VGA - neither in resolution nor in color depth.
You can clearly see that most games - the ones with many colors - only use a horizontal resolution of 160 pixels - which is also the resolution of choice with the older Atari hardware and also often used by the C64 for example.
While 320 horizontal pixels were indeed possible this - like with the 8-bit Atari computers - restricted the amount of colors dramatically: Only two brightnesses without resorting to programming tricks like display interrupts (quite well known at the time, though) which had other restrictions.
So, while it is possible to get more colors with 320 horizontal pixels the "rules" are pretty much strangulating the programmer and they weren't really employed by commercial software.
VGA on the other hand - especially the mode that is most often associated with it: 320x200x256 - is more of a clean engineer's approach to computer graphics and it shows. This mode has four distinct advantages:
- A resolution of 320x200 square pixels. No wider than tall pixels like with a resolution of 160x200 which means circles are round...
- An unrestricted color palette of 256 colors - all of them controlled by color registers from an RGB palette of 3 x 2^6 = 2^18 = 262,144 colors. Changing a register meant changing all pixels using that color in an instant.
- A continuous frame buffer of 64.000 bytes (320x200x1 byte). No weird addressing scheme with holes (Apple II), non line addresses
- This mode like practically all PC graphics modes (and therefore the software using it) runs with 60 Hz wherever in the world you are - so US games software had no problems in Europe and vice-versa. A thing that really plagued games on earlier machines.
Yes, VGA had no 100 sprites and no raster interrupts (AFAIK) but for a good part they weren't needed at all. First of all there were "enough" colors, especially for handdrawn graphics and secondly as every pixel consists of a single byte there's only a limited amount of computation needed to manipulate the frame buffer (for example for moving objects). Now throw in a fast CPU (which had to manipulate the graphics at the time) and you have a good, powerful system. All in all it was equally good for displaying presentations, digitized photos and game graphics.
The 7800 is still far from that, even though it may be sufficient for TV sets of the period and, of course, was clearly more advanced than the 5200.
take care,
Calibrator
take care,
Calibrator