I must be very bad at math but here is what I came up with...
Consider a game that runs on the 32X alone at 60 fps and has 2 background planes & 1 sprite plane (just like the Genesis vdp). Since the 32X is powered by a flying beaver, let's suppose 2X as a middle to worst case overdraw.
Post by oompa loompa on Jun 23, 2005 20:25:02 GMT -5
banning's for dorks, i'd rather delete the post and let you continue to whine =P, joking =D
it is hard to tell how many instructions the sh2 will put into one pixel because there are many factors that come into play like memory wait states, or bus acknowledges/waits for parallel processors. if you look at some of my demos, like the scaling and rotating demo, you can see that just by using one sh2 for drawing is pretty slow. the scaling demo was written in assembly, and is still slow because there were many pixels to take care of.
that zyrinx demo doesn't look like it was for the 32x, but rather the sega saturn. the 32x only has a frame buffer, and does not have any graphics accelerators in hardware like the saturn does. it'd be possible to create that demo on a 32x, but the player screen would have had to be hella small
i'd rather delete the post and let you continue to whine
Nahh, I would open another thread and you'd have to delete it over & over. That would take up to much on your time. I prefer to let you work on your next beast so I'll just quit on that matter =P
it is hard to tell how many instructions the sh2 will put into one pixel because there are many factors that come into play
You forgot about the most important one, the possibility to process multiple pixels at a time with careful planning. But if you fetch textures directly from the ROM, well, you're limited to 16-bit accesses anyway (unless the cache comes into play).
like the scaling and rotating demo, you can see that just by using one sh2 for drawing is pretty slow
What !?! Looking at the speed I thought it was running on the 68K! ====P I'm just kidding BTW. I think that what you did on the 32X is absolutely awesome, really.
that zyrinx demo doesn't look like it was for the 32x, but rather the sega saturn
Have you looked through the entire demo? The voxel scene at the end just can't be rendered with the Saturn VDPs. Which basically leave the Saturn to the same spot as the 32X. Unless they make some crazy use of the Saturn's DSP (but how can you do a voxel mapper with a DSP, leave that to the gurus over at Zyrinx)... Speaking of Zyrinx, I'm sure you've seen Hard-Wired (RedZone) & SubTerrania for the Genesis...
it'd be possible to create that demo on a 32x, but the player screen would have had to be hella small
...or they simply render the scene at a lower rate (10 FPS or so) which I believe is the case.
My opinion is that the 32X is great for what it was designed for, flat shading in RLE mode. It can also do cool 2D blending effects in RGB mode.
I have a "small" electronic project in mind beside attaching an IDE channel on the Dreamcast expansion port =D. Do you think it's possible to transform the 32X (without the Genesis) into a portable console by replacing the BIOS and overriding the S-Video output into LCD output. (The goal is not to run 32X games BTW...). The 32X PCB is small so I think it would fit into a tiny project box with some surgery...
/* When brain power fails, brute force prevails! */
Yeah, it would work, however, it requires several clock/video signals to come both on cartridge and video-in...
For the zyrinx demo, i guess they are all true. If you look closer, the textured and shaded polygon demo have an horrible framerate... The vorxel demo is pretty smooth cause they are demo coders and they certainely have some tricks (the vorxel itself is pretty low rez), the remaining things are 2D elements (maybe some flat polyes also)...
If you play BC racer, you'll understand (it displays a "3d" plane, some huge sprites).
The most strange things are: the first polygon demo that have some fog (why not, but it is strange assuming they used the line filling method) and the lensflares
Post by Tom Maneiro on Jul 2, 2005 16:00:49 GMT -5
Do you think it's possible to transform the 32X (without the Genesis) into a portable console by replacing the BIOS and overriding the S-Video output into LCD output. (The goal is not to run 32X games BTW...). The 32X PCB is small so I think it would fit into a tiny project box with some surgery...
No without a Genesis... where you will put the 68K, the VDP and the rest of the chips? Unless you want to make your own Genesis
Ha, its to make a portable... Because, when i'm speaking about "additional signals" required, I mean, several clocks... This certainely takes some place. Also, the 32x board need to be set "running" and this is set using a special register (inside the 32x)...
I just say it's possible but i don't have any idea of the signals you need to input.
the 32x needs to be initalized by the 68k. in short, unless you found some way to send fake data to the 32x to get it to boot, it wouldnt work without the genesis.
also 32x games use the ym2612, psg and z80 in the genesis (knuckles chaotix) its just not possible to use the 32x alone, unless you only want it to render stuff on the screen with a series of tones from the PWM.
and in terms of pure horsepower, 32x > genesis. 2x Hitachi SH2's @ 23.5 MHz (also mind that they are underclocked by alot. their normal speed is the same as the saturns sh2's at 28.7 MHz)
i have overclocked the 32x before to 47 MHz each, and if the games didnt rely on their own lag to run, all games on the 32x would pwn. you can still determine which sh2 the game is using for the rendering and only overclock one of them to get the game to run faster, but it may make it unstable.
im also not liable if you fry your 32x in the process.
the 68000 sending data to the sh2's is not a hardware lock, its to initalize the processors. just think of the 68k as a bus controler. if its not present, you can send all the data you want to the sh2's, they just wont do anything.
i have attached debuggers to the 68000 while games were running, and occasionally if an exception occours, they have to be re-initalized.
just go find a cheapy old crackerbox macintosh and de-solder the cpu and use that to make a new controler.
I'm not so sure =P The only thing (if i remember) required to startup the 32x is to send a value to a address (aden=1)... (this is easy to do using simple hardwiring to the 32x genesis-side connector i guess). Once ADEN=1, the sh2's startup the code read from the cartridge...