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DS development > Some questions (3D, files, etc)

#58686 - Webez - Tue Oct 25, 2005 11:29 am

Hi.
I have just began my final year university project (a tactic-rpg for ds) and I have a lot of questions. Hope some of them can be resolved.

1. What are the benefits of using display lists in ds? I know that in opengl it is a faster way of rendering vertex because they are precompiled. Is it the same here? Are they also static?

2. Right now I am using a flashcart for programming so gbfs seems the only way of accessing files without merging them with code (.bin). So I have three alternatives
a. Continue using flashcart with gbfs
b. Wait for an update in libnds which allows me file access
c. Buy another device which can access files like fat

What do you recommend?

3. The game is going to have 3D in the upper screen and 2D in the other. The problem is that as far as I can see, only the primary screen can be in 3D mode or frame buffer mode. And the problem is that I want to use in the subscreen the stylus to paint (so I thought frame buffer would be the best mode for this but it can't be used in the subscreen).Any solutions?

4. The scenario will be in 3D (like 32 bits tacticsrpg) but I don't know what to do with characters. I was considering doing them in 3D instead of 2D but isn't it going to be a problem for? I think so beacuse in a tactic-rpg are a lot of characters in screen at the same time and animations can also be a problem.

It is going to be a log termn project (until may) so I hope you can help me during this time. Thanks

PD: Sorry if my poor english bothers someone.

#58699 - inferno - Tue Oct 25, 2005 1:37 pm

I'm not sure about the 3d only available to the mainscreen but can't you just lcdswap it?

Anyway I'd recommend using 2d for the characters. If you can get your hands on Medieval total war (or if you've played it before) you'll know that 2d characters and a 3d environment can work together flawless in a RTS game.
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#58704 - mike260 - Tue Oct 25, 2005 2:17 pm

Webez wrote:
Hi.
I have just began my final year university project (a tactic-rpg for ds) and I have a lot of questions. Hope some of them can be resolved.

1. What are the benefits of using display lists in ds? I know that in opengl it is a faster way of rendering vertex because they are precompiled. Is it the same here? Are they also static?


Display-lists reduce CPU load, because the CPU doesn't need to interpret them in any way - it just throws them at a fixed memory address and the hardware takes care it. If you didn't use them, you'd have to have your own geometry structure, and the CPU would have to interpret it and route various bits to various registers.

Also, a well-optimised display-list will use a *lot* less RAM.

They're not completely static; if you *really* want, you can go poking around inside a compiled dlist and changing values, but I can't think of a good reason to ever do this. You wouldn't want to try animating the verts within a dlist, for example.
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#58711 - Webez - Tue Oct 25, 2005 3:24 pm

Thanks a lot. I'll try to use display lists then. Another thing that has come to my mind. Is there a way to know how much memory is available? Because with actual emulators is difficult to debug and I am planning in using a debug console.

#58723 - dovoto - Tue Oct 25, 2005 4:00 pm

I am soon to implement proper gl ish display lists (there will be two ways to use them, one of which is to call sepcial display list versions of the gl functions and the other is to #define in the display list state machine so you can use regular openGL calls inbetween a glNewList() glEndList() call)....as soon as i find about 8 hours to spare to the endevor ;)
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#62823 - psimon - Tue Dec 06, 2005 7:34 am

dovoto wrote:
I am soon to implement proper gl ish display lists (there will be two ways to use them, one of which is to call sepcial display list versions of the gl functions and the other is to #define in the display list state machine so you can use regular openGL calls inbetween a glNewList() glEndList() call)....as soon as i find about 8 hours to spare to the endevor ;)


that sounds awesome!!!
i am really looking forward to your next release.
make sure you post when they go up!

thanks
dovoto!