Search found 762 matches

by Sik
Sun Mar 17, 2019 8:26 pm
Forum: SGDK
Topic: SGDK and MD details, limitations...
Replies: 11
Views: 281

Re: SGDK and MD details, limitations...

The problem with slamming the stack right in the middle of RAM is that now you have to organize more carefully where you store anything as you basically made the space non-contiguous now. The ideal thing would be to assign variables from top to bottom and then stack right below all allocated variabl...
by Sik
Sun Mar 17, 2019 8:20 pm
Forum: Demos
Topic: Cpu speed test rom (md+scd)
Replies: 17
Views: 633

Re: Cpu speed test rom (md+scd)

Wouldn't the TV barf at the resulting signal if the VDP clock goes off? And yeah, everything is fed from a single master clock but also they get divided clocks (so things run at different rates) so it's still possible for only one component to have a clock problem if the issue happens between the di...
by Sik
Sat Mar 16, 2019 10:56 am
Forum: Demos
Topic: Cpu speed test rom (md+scd)
Replies: 17
Views: 633

Re: Cpu speed test rom (md+scd)

I didn't check that code, but I suppose vblank is involved? That's how I did the measurement in 68kbench (check how many times the loop runs for 10 frames). You do need to account for the difference between NTSC and PAL, mind you (as well as the fact that the code will run slower if running from RAM...
by Sik
Wed Feb 27, 2019 10:40 am
Forum: Demos
Topic: Tänzer, a "ninja" game (Dev Diary thread)
Replies: 256
Views: 27634

Re: Tänzer, a "ninja" game (Dev Diary thread)

Wait, game is already done? I'm with Stef here, I'm pretty sure you could have gotten more orders with better communication, honestly it feels as if anybody who wasn't actively checking the kickstarter page didn't hear much about what was going on (I didn't even think it was that close to done alrea...
by Sik
Wed Feb 27, 2019 5:28 am
Forum: Video Display Processor
Topic: Question about 512 colors in TITAN demo
Replies: 3
Views: 378

Re: Question about 512 colors in TITAN demo

1) No S/H involved (so the 512 color master palette) 2) It's changing a lot of colors every line (like the moose chase scene in Mickey Mania) 2b) which also means it's dropping sprites due to disabling display during hblank (the "your emulator suxx" message shows up if too many sprites are rendered)...
by Sik
Mon Feb 25, 2019 8:50 pm
Forum: Blabla
Topic: 68000 Arcade systems programming
Replies: 14
Views: 916

Re: 68000 Arcade systems programming

I'm assuming Tomahomae wasn't referring to the programmer manual (and yeah, some of the branch options often are skipped). BPL = branch if plus (if result is positive) BMI = branch if minus (if result is negative) They don't fall under the obvious comparison stuff (=, ≠, <, >, ≤, ≥) so I can see how...
by Sik
Mon Feb 25, 2019 2:42 am
Forum: SGDK
Topic: Simple noob Pals/tiles question
Replies: 13
Views: 977

Re: Simple noob Pals/tiles question

Yeah, that 5th palette is just so you can still see the tiles in the VRAM debugger even if all palettes become a solid color from fading or the like. It doesn't exist on the actual hardware.
by Sik
Sun Feb 24, 2019 7:16 pm
Forum: Blabla
Topic: 68000 Arcade systems programming
Replies: 14
Views: 916

Re: 68000 Arcade systems programming

Oof, I'm guessing that comment should have been after a0, not before (I haven't looked but I'm guessing the address there is where $2C(pc) actually points).
by Sik
Sun Feb 17, 2019 5:09 pm
Forum: Demos
Topic: Cpu speed test rom (md+scd)
Replies: 17
Views: 633

Re: Cpu speed test rom (md+scd)

Probably explains why the CPU speed got measured a bit too slow (because some cycles are lost to refresh, even the cartridge slot gets a few, while RAM gets a lot more).
by Sik
Thu Feb 14, 2019 9:04 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 9
Views: 1028

Re: Help scale and rotation sega genesis

I mean, there's always the Sonic 1 approach :​v https://www.youtube.com/watch?v=2MKByhhm_S4 And one of the Seven Force forms in Gunstar Heroes is a gun that takes the same approach (the boss as a whole is like that, really). That still requires sprites for several angles but not for all of them (mot...
by Sik
Tue Feb 12, 2019 8:54 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 9
Views: 1028

Re: Help scale and rotation sega genesis

But that's Sonic Mania, it's running on hardware that's both a lot more powerful and that has a tad more of memory.

Sonic 3 didn't have those guns at all.
by Sik
Tue Feb 05, 2019 9:26 pm
Forum: SGDK
Topic: Circular Transparency
Replies: 5
Views: 287

Re: Circular Transparency

I don't think I've seen anybody pull it off on Mega Drive, so that should tell you something already (on SNES it's easier as you can exploit its window feature for that purpose). Only obvious suggestion that comes to my mind is to redraw the tilemap (literally move the holes themselves in it, rather...
by Sik
Sat Feb 02, 2019 5:37 pm
Forum: Super 32X
Topic: Interlaced rendering?
Replies: 9
Views: 909

Re: Interlaced rendering?

Also it just hit me that 32X's forced double buffering is probably going to get in the way pretty hard (as what will be in the framebuffer are the contents two frames ago, not one).
by Sik
Fri Feb 01, 2019 11:46 pm
Forum: Super 32X
Topic: Interlaced rendering?
Replies: 9
Views: 909

Re: Interlaced rendering?

The interlaced mode on the Mega Drive is mainly intended for doubling the resolution, not halving it. It'd end up doing exactly the opposite of what you intend.

Also I don't think the 32X even supports it, but I could be wrong.
by Sik
Fri Feb 01, 2019 5:47 pm
Forum: SGDK
Topic: Sega Genesis Dev Kit (SGDK)
Replies: 772
Views: 327796

Re: Sega Genesis Dev Kit (SGDK)

Well, later consoles (and some DOS programs :​v) would resort to "overlays" which are chunks of code that can be loaded and unloaded as needed… I suppose that bank switching support on SGDK would require a scheme like that. And yes, this is something that needs help from the linker (to put data in o...