GameEngine

Yes. But it is not only that they did not make any improvements to the chips, they were just trailing competition since '82 with what they offered. First in '82 with 1200XL, which lacked built in Basic. C64 had it. Greediness does not pay (I read C64 bill of material was around $130 so I think it was similar for 1200XL and both were introduced at four times the price of BOM or so. This makes me think they could do even more. Even if they no longer had anyone who could improve existing chips, I'd bet that, in the 1200XL case they would be able to fit both Basic and second Antic. This is what I consider more then enough to compete with C64 and the rest of world) Then in '83 with 800xl. The product was almost right. Personally I preffer it over C64 for its good quality but technically, even though the original '79 design was ahead of its time, it was aging. If only they introduced it a year earlier (thus avoiding 1200XL fiasco at the same time). '85 XE line introduction at bottom low prices was everything Jack Tramiel could do when he took over. Low-end marked was lost to competition (he created). Further investments made no sens (also, it seems to me that he inherited stock full of parts to build 8 bits). Still, 65XE starting at $100 was a great opportunity to poses once $1000 computer ('79 Atari 800) in a new very modern case.

lets see... ... seems they were not aware there will be MPEG2 TVs . It is a constrain but isn't that easier on your eyes this way? ... you are right that 8 makes more sens bit wise and 4 makes more sens byte wise, but given this, 9 makes more sens to me. ... and still no other machine could compete for at least 2 to 3 years (correct me if I am wrong). To me they did a great job.

C64's 12 bitness gives it to much advantage to be neglected. One of the two main advantages (being color resolution and sprite subsystem) over the Atari 8bit would be lost if it is taken away. Just take a look what happend when Commodore decided to make C16/C116/C+4 out of C64. None can compete. C64 is 12bit just where it needs to be (well...almost). PS Only if Jay Miner stopped half way for a minute and designed 12bit Atari before he went for 16bit Amiga we could tell the real value of C64.

The fact that C64's video processor VICII has 12bit data bus was already explained in this thread by others. Now, it is obvious that VICII is the most powerfull chip of the C64 and it makes C64 what it actually is. 6510 built into it has the same relevance as 68000 in Jaguar64 (would it be anything else it does not make a difference). C64 being 12bit has a funny part to it: How come can C64 be the best 8-bit computer while it is actually 12-bit?

My preference is exactly the same ie if it is not a productivity app programmer should go for the full screen. For the owners of old TVs: Waht a delight it will be when your new TV gives your old Atari a new dimention.

I am 100% sure that even demo of Crownland deserves it own thread. It rendered me speachless when I saw it running (last time I was supprised as much was when Commando cartridge was discovered and dumped) Simply beatifull! Perfect design! Marvel! Fun not only to play but to wach as well. PS I even transfered recorder video of the game to my mobile phone (thats a pity there is no Atari emulator for Symbian) to be able to admire its qualies.

There is so much talk about Commodore computers in this thread one does not need any C64 forum I thing 8-bit Atari holdes very well when compared to C64 even though C64 (oposite to the later C+4 and earlier VIC20) is really 12-bit computer ! How come C64 is 12 bit? Its video processor (VIC II) is 12 bit (same as Atari Jaguar64 is 64bit). Now back to main topic. Atari 800XL I bough blew everything else I saw or heard of when I was a child. Direct comparison against ZX Spectrum made the owner run to the store and buy Amiga (real fact). Both Spectrum and C64 build quality and electrical design place them as well .... chip toys. I have to admit thoguh that: Apple II and Amstrad's hardware (especially 128) was better suited for productivity apps. C64 hardware eventually proved better for gaming (new Atari game Crownland raised my doubt here, what comes next?) but it lacked many early hits (so in early days it was not an alternative).

Speccy, Atari and C64 were all very good computers ( for the price that is, many thanks to C. Sinclair and J.Tramiel)

manager.ZIP Still work in progress. PAL only Should be 25 frames a second. Both ways wrap-scroll in character mode plus five double-buffered software sprites plus five plain PMG sprites. Use stick to move players. Software sprites interact with inverse characters - in case you want to know which are which. Regards, GameEngine.

Thanks guys for the hints and offer to help which I really appreciate (my lack of experience means I might go terribly wrong with some of my assumptions). Actually I read this forum for some time and I saw both techniques you mentioned but these do not seem to fit my needs exactly. I tried to design the scrolling engine so it capable of virtual screen (like Tiger Attack) so some interaction with off screen objects is easier. Also I plan to go for 25 frames/s so I think I need my own software sprite engine. Basically want to have things well balanced not willing to trade neither framerate nor color (thus the usage of overlays) just to show plenty of fully independent sprites. Now report on progress: I did some optimizations to the code and instead of not fitting at all within one frame I have now around 8000 free cycles per frame. I base my judgment on the vertical position at which the last sprite stops to flicker, it seems there is ~10 rows at which CPU is no longer busy with sprites, now 10 rows * 8 lines * ~100 cycles/line = 8000? cycles/frame. If the above true (I believe it is) it means that I have enough time left to maintain P/MG as I planned 5(plain) + 4 (reused). Eventually I plan to go for 25 frames/s and double-buffered PMG so I will have all my sprites and no flicker. MANAGER2.ZIP Please do share with me your comments and remarks. GameEngine

I do not know what drives me but I am pretty sure that I will write the very first game of mine for XL computer this year. I realized that what I need at first is some game engine with a feature list like this: - character based playfield (some action)which is as much as full screen as possible - playfield rolls both ways, so if desired it can but does not have to be fed with additional data - horizontal and vertical scroll which is not that hungry for resources - 1 bit (ORed = fast, 1 common color extra should make sprites look good enough) software sprites to use as PMG underlays (thus width should match PMG so 8 color cycles), preferably 5 of these, will see So far I have scroll and soft sprites working (well, kind of - see bellow): MANAGER.zip (use joy0 and cursor keys to initiate action, for both only 4 main direction allowed) The problem is that current incarnation of my Engine is way to slow (thats why you see flickering and there is more when sprites are at the top) ! For the screen I move 128 bytes (width) and update 32 line (2 lines hidden) adresesses (lower byte) for horizontal and roll full 32 adresses for vertical scroll. I think the real problem lies with software sprites where, so far, I used horizonatal preshifted data for it and was trying to avoid to many loops which unfortunatelly is not enough. I write hoping that you will keep your fingers crossed so I am succesfull in optimizing it to the point where playfield scrolls both ways and 5 software and 5+4 (reused) PMG sprites gets refreshed within one frame (I really hope it is possible) thus every other frame is spent for game logic and character based action. PS If I am succesfull I plan to share version of this engine available from Atari Basic to facilitate game prototyping. If not, well .... then I'll lower my expectations I think cutting on the number of sprites and ability to scroll vertically (the later option looks especially interesting as it would allow me to move some processing into the next frame. On the other hand it would be more suitable for sideways shooter then. Hm..). GameEngine