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DS development > Quick Keyboard Stuff?

#157082 - thegamefreak0134 - Mon May 19, 2008 2:20 am

I've gotten to the wonderful stage of saving files with my image program, and I've hit a slight snag. I'm basically out of VRAM on my main screen, which means I can't really pull up a new background with new fancy memory to throw a keyboard on-screen.

(I have to use basically all of my background memory for engine A when I'm handling a 24bit PCX file, as I need to go into full bitmap mode and that chews up memory when it goes fullscreen. I have some wiggle room for 256 color and 16 color images of course, but I really want to leave support for 24bit images in, as it's kind of cool.)

I was wondering if there is a keyboard already built into the library that I can throw down onto the subscreen. If such a thing existed, it would make my life a little easier. I would only really need to be able to poll it for individual characters, although if it were possible to have one output a string that would be neat as well. I'm more than OK with writing a keyboard myself, I'm just wondering if it's already been done, as it will save time and let me release the alpha for this thing a lot faster.

Thanks!

-thegamefreak0134
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#157085 - Dwedit - Mon May 19, 2008 2:27 am

The DS can't even display 24 bit images, so why bother?
I think the most the DS can do is two 15 bit images overlaid on top of each other with alpha blending.
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#157087 - tepples - Mon May 19, 2008 3:09 am

I've made the beginning of an on-screen keyboard that should fit into 8 KiB of VRAM, using a tweaked 16-color "bitmap" mode. In fact, I made a whole library for this bitmap mode just so that a program could put an overlay on main F (16 KiB) or sub H (32 KiB) while using banks A-E for 3D textures and palettes. You can look at it or try my prototype.

And I'd bet that this "24-bit" display is just a spatiotemporal dithering of an image with 8 bits per channel down to 5 bits per channel, in much the same way that cheap 6-bit LCD panels try to display 8-bit data.
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#157111 - thegamefreak0134 - Mon May 19, 2008 11:56 am

Ah, incorrect both of you. I'm allowing the users to edit the PCX file in 24bit mode, but I'm only displaying it in the usual 15bit mode. My mistake for not clarifying that. I've got to be able to support a full screen of 16bit image at a time, which is why I'm crunched for memory at the moment.

It's occurred to me that I can probably re-arrange my VRAM, what I have now was a quick-and-dirty job to get up and running fast. That should let me double my current space, which will be nice.

I'll take a look at that keyboard tepples, thanks! For now though, I'm going to sleep. Very tired... Is late here. Zzz...

-gamefreak

*edit* tepples, my apologies, you are actually right now that I look at it twice, except that I don't dither it. Don't really see the need, the selling point of this editor is to see your sprites on the actual DS for color comparison. ^_^
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