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DS development > Method for 3D on both screens

#39571 - haruguchan - Sun Apr 10, 2005 9:11 am

I've noticed while playing some super mario minigames 'Bounce and Pounce' in which you draw carpets form avoiding mario to fall off that DS can use 3D on both screens at the sime time.
The sprites of the upper screen are NOT pre-rendered, if they were pre-rendered it would take a lot of space. Well, when i lost and the three marios fell off, it shown the 'game over' and the 'retry' and 'quit' buttons like if they were at 15 fps.
It could be that ONLY one screen is drawn while the other remains halted until the next frame. The ones who have super mario, check the minigames like that and watch the framerate drop of 2D graphics.

#39574 - octopusfluff - Sun Apr 10, 2005 10:35 am

The theory that it alternates frames is not a new one, but it's important to note the basic framerate has been documented at 60fps, with the expectation under that theory that 3d on both screens would be at 30fps.

I think the 'framerate drop' you're reporting is a stylistic item, not a technical one.

#39585 - haruguchan - Sun Apr 10, 2005 2:21 pm

Super mario runs at 30fps with one 3D screen (metroid too). But in the menu, the 3D runs at 60fps. In that minigame it seems to run at 30fps in both screens, but the 'star transition' and the 2D movements are 15fps, not 30. I don't think they would leave it at 15fps when it could be 30.

#39602 - Lord Graga - Sun Apr 10, 2005 6:28 pm

Yes, you can split 3d between both screens, dropping the framerate to 30 fps. I was told so by an official developer.

#39650 - octopusfluff - Mon Apr 11, 2005 1:50 am

I took the time to load the minigames to try to see this '15fps' behavior you speak of, and I'm not seeing it.

I doubt you're counting the frames in your head, and Nintendo wasn't kind enough to put an fps counter in the corner, so we can't exactly prove it either way..

But to me that doesn't look like it's 'dropping framerate'. That looks me that they got the transition effect that they wanted.