That's what I thought that was, but the inherent lack of stability of that stuff, when I merged it, essentially told me that none of it was going to work as-is.
I was using the value of RT_BITMAP1, passed through sdci[n]/10000, with zscriptDrawingRenderTarget->GetBitmapPtr(bitmapIndex);
Effectively, zscriptDrawingRenderTarget->GetBitmapPtr(RT_BITMAP1/10000);
That seems to work everywhere else...?
Would you making making the entire screen bitmap, as it is rendered each frame after drawing objects/sprites,including the passive subscreen, available as a render source through that function?
I managed to merge enough from allegro 4.4.2 thus far, to get draw_sprite_ex to work, but I;m still missing some component that is critical to rotate_sprite_trans and pivot_sprite_trans. I took a break from drawing functions, to add Link->Diagonal, and Link->BigHitbox, both with abstraction functions, and I know that Diagonal works. I haven't tested BigHitbox, primarily because of the set-up time to make big link tiles.
At least I'm sure now, that I comprehend how to add class variables, properly. That will help with Itemdata, although I'm uncertain how to add an ID field to the classes, permitting for example, 'this->ID ' in item scripts, to grab itemdata values.