Re: [AD] clipping line algorithm

[Robert Jr O. <roh...@vi...>]

Sven Sandberg wrote:
> Sorry, there must still be some misunderstanding. As I interpreted your 
> previous message, you want the following to hold for bitmaps with the 
> "linear" flag set:
> 
> (1) it is possible that someone uses bmp_read on the bitmap.

That's not necessarily true. Once upon a time, AllegroGL supported 
bmp_read/write on an OpenGL context. IIRC, bmp_read/write also works on 
ModeX (plannar) bitmaps.

The trick is that bmp_read/write_line *is* in the vtable. Memory 
allocation and remapping can then be done there, although it's very 
tricky and the API for that should be improved.


> (2) it is impossible that someone accesses the bitmap without using the 
> vtable.

You mean, through bmp->line[]?


-- 
- Robert Jr Ohannessian
http://bob.allegronetwork.com/