nanogui: Microwindows for Hercules
Subject:
Re: Microwindows for Hercules
From:
Perry Harrington ####@####.####
Date:
15 Jul 1999 20:01:12 -0000
Message-Id: <199907152047.NAA12710@alpha.apsoft.com>
> If using writepixel, there need be 16 writes to videomemory.
> When using the native HGC linedraw, there need be only 4 writes to videomem.
>
> Also, the algo. uses an incrementing form of bresenham. Very standard,
> yes. But the incrementing scheme takes into account the bizarre
> HGC memory layout.
>
> Regards,
> Jakob Eriksson
>
>
Why not take the approach that Linux takes with the module:
Create the driver structure, have the primitives referenced in the
driver structure. If the driver doesn't implement a primitive, set
the structure member to NULL, and the driver loader will take care
to use the builtin function. EG:
struct driver {
ptr_t hline
ptr_t vline
ptr_t bline
...
} DRIVER;
struct driver herc_card[]={
herc_hline,
herc_vline,
NULL
};
That way you can have driver optimized primitives or rely on the default,
which just calls write_pixel.
--Perry
--
Perry Harrington Linux rules all OSes. APSoft ()
email: ####@####.#### Think Blue. /\