LibNDS GL_CLEAR_BMP? Or, can I somehow use this to render more than 2048 polygons?

[Poketard]

I'm trying to do some trickery to render more than 2048 polygons, and currently the major obstacle is the fact that the DS clears the screen before rendering. I did some research and found there's no way to disable it, but there is a separate mode of clearing that allows you to fill it with a bitmap instead. Unfortunately, I have no idea how it works because I can't find any documentation on it. So I was wondering if there's anyone here who'd know more about it; or, more about my goal to break the DS' limits in general.
Edit: so, I did some scouring on gbatek and found it uses texture slots 3 & 4. Unfortunately, there doesn't seem to be any way to get the depth buffer, so this seems like a dead end. I swear, this automatic clearing is the bane of my existence.

 

[elhobbs]

I'm trying to do some trickery to render more than 2048 polygons, and currently the major obstacle is the fact that the DS clears the screen before rendering. I did some research and found there's no way to disable it, but there is a separate mode of clearing that allows you to fill it with a bitmap instead. Unfortunately, I have no idea how it works because I can't find any documentation on it. So I was wondering if there's anyone here who'd know more about it; or, more about my goal to break the DS' limits in general.
Edit: so, I did some scouring on gbatek and found it uses texture slots 3 & 4. Unfortunately, there doesn't seem to be any way to get the depth buffer, so this seems like a dead end. I swear, this automatic clearing is the bane of my existence.

My understanding is that there is no depth buffer to capture. The problem seems to be that all of the options that are available require a lot of vram - display capture, rear color/depth bitmaps etc. and the even if you are clever and figure something out you are left with no vram for textures and poor frame rates. At that point a software renderer seems like a simpler option.
That being said the 3D both screens example uses display capture to render to both the bottom and top screens, but perhaps a similar scheme could be used to render the left/right side of a single screen?

 

[banjo2]

but perhaps a similar scheme could be used to render the left/right side of a single screen?

I believe Pikmin-NDS and Super Mario Galaxy DS do this