Search found 500 matches

by Miquel
Fri Sep 16, 2016 11:55 pm
Forum: SGDK
Topic: Small floating point numbers
Replies: 29
Views: 4670

Re: Small floating point numbers

"Serious" games usually use fixed points instead of floating points in game logic because they are way faster. You should use them for things like "position" and "speed", there is a notable difference in response. The big handicap is you no longer have so many decimals, but is strange to use them in...
by Miquel
Fri Sep 09, 2016 6:59 pm
Forum: Megadrive/Genesis
Topic: How to build a self-running demo?
Replies: 11
Views: 3153

Re: How to build a self-running demo?

Natsumi, if fact there are 3 ways of controlling player in games like sonic, we have to add a 3rd option: when in normal gaming control is taken from player, usually to reach some point. In Sonic is used for example to get out of the current level. So doing it is quite easy but requires some thought...
by Miquel
Thu Sep 08, 2016 10:20 pm
Forum: SGDK
Topic: structs with unions
Replies: 4
Views: 1283

Re: structs with unions

You even can use unnamed unions if you don't like that much verbose. Is my opinion that unions are the best memory manager there is for genny.
by Miquel
Wed Sep 07, 2016 8:08 pm
Forum: Megadrive/Genesis
Topic: How to build a self-running demo?
Replies: 11
Views: 3153

Re: How to build a self-running demo?

Already done, thanks to gens kmod (and you Kaneda!) it was a piece of cake. I was about to talk about it but I'm very happy you found it yourself! I made this feature yearrrrs ago, while working a canceled-coming-soon game which required the demo mode. I know that, at some times, I made a demo to he...
by Miquel
Tue Sep 06, 2016 8:06 pm
Forum: Megadrive/Genesis
Topic: How to build a self-running demo?
Replies: 11
Views: 3153

Re: How to build a self-running demo?

TmEE co.(TM) following your suggestion I found that "Gens Kmod" seems to be the better option, in my case, for recording input. From the help files: ----------------------------------- - GMC File Description - ----------------------------------- uchar Format //what is on the GMC File, add the needed...
by Miquel
Tue Sep 06, 2016 4:33 pm
Forum: Megadrive/Genesis
Topic: How to build a self-running demo?
Replies: 11
Views: 3153

How to build a self-running demo?

Do you remember old games, where if you don't press start in the title the game starts but plays by itself? How is that accomplished? Right now I'm thinking of an emulator and a pc program that captures keys presses, then pack all this data into more compact form and inject directly to the input of ...
by Miquel
Fri Sep 02, 2016 8:27 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

Ok, just to recapitulate, you don't need hcounter to know in which line you are in a horizontal exception if you vertical exception last less than a vertical blank. So: - In a standard frame just be sure that the above is accomplished. - On a loading frame (when you fill most of the VRAM) use hcount...
by Miquel
Wed Aug 31, 2016 2:28 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

I'm baffled, when I was going to give up and say there can be only up to 224 HBlank exceptions (in NTSC), because my program seems to work this way, you show me a document with a 225th H exception. I really don't know what to say. Then it could be a 226th exception and so on...? H exceptions stop to...
by Miquel
Tue Aug 30, 2016 4:51 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

When DMA is in progress the CPU is halted, no ints will happen or anything else. ¿ Do you mean inside VINT exception ? For sure a fill operation can be interrupted, and maybe when your are displaying, VPD goes more slow so perhaps memory access is interleaved, just speculating, I really don't know....
by Miquel
Tue Aug 30, 2016 3:05 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

Ive never had timing issues on v-int. Even with a lot of DMA's happening durint it, h-ints start at line 0. You should invest in fast and clean code durint v-int either way, or it could take a lot of unnecessary CPU time As far as I know you should deactivate exceptions in vblank because if you int...
by Miquel
Mon Aug 29, 2016 3:33 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

This is a very quick way to issue VDP commands and write to VRAM, CRAM, and VSRAM. As a bonus it uses no registers and uses only 24 bytes of RAM. And its really fast. I will take a note on this, and see how it works. But if I remember it correctly, I wrote it some time ago, one of the problems is y...
by Miquel
Sat Aug 27, 2016 12:08 am
Forum: Sound
Topic: Set volume of both sound chips
Replies: 3
Views: 4101

Re: Set volume of both sound chips

For YM you have to keep track of current algorithm and adjust TL equally on all output operators. If I have understood you well, that is like simulating the whole chip, it will involve too much computing. Maybe it will be sort of ok if the next note (entry) on each channel will be readjusted in vol...
by Miquel
Thu Aug 25, 2016 3:32 pm
Forum: Sound
Topic: Set volume of both sound chips
Replies: 3
Views: 4101

Set volume of both sound chips

I'm working on a game and right now I have two pieces of code: one controls FM music and it runs on TMF modules, done throught TMFmaker and based on Shiru's code to run tfd files. The other controls PSG sound done with Deflemask, and converted to VGM and then to PSG, the code that runs it is done by...
by Miquel
Wed Aug 24, 2016 5:43 pm
Forum: SGDK
Topic: Line scrolling
Replies: 9
Views: 2984

Re: Raster perspective for background layer.

My best guess is this is doing using horizontal scroll per line. Very much like full plane scroll, you apply to every line the same value except the ones which are doing this effect which have higher rations of scroll as they are close to the viewers eye.

Perhaps someone can tell more details.
by Miquel
Tue Aug 23, 2016 2:02 pm
Forum: Video Display Processor
Topic: VDP access from Z80 questions
Replies: 16
Views: 8521

Re: VDP access from Z80 questions

I guess you're not using sgdk (which add overload for hint handler). No, I'm not using SGDK, aldo at the beginning, when I didn't know very much about MD internals I follow up it very close. You said your hint is already as fast as possible, do that mean the instructions sequence is similar to: mov...