Re: [AD] Using system mouse cursor

[Chris <kcat@xxxxxxxxxx>]

Evert Glebbeek wrote:
> Basically, what we have now is thwe 
> following division of mouse pointers:

Right. Except on systems where Allegro implements a true hardware 
cursor, you can't have a system pointer since there is no default cursor 
there. IMO, it would cause an unnecessarry system-specific option on top 
of something that's already system-specific.

Basically with your way, the programmer would have to try to enable the 
hardware cursor. If this fails, system behavior won't be all that 
affected since Allegro will still draw the pointer. Then he has to try 
setting the OS cursor type. Now, this will only work on systems where 
the OS has default cursors.. if it doesn't work, the programmer has to 
do addition work to try and get suitable behavior.

With my way, the programmer still has to try setting up the hardware 
cursor, but beyond that, the API makes no distinction between a true 
hardware mouse, or an OS-based one. If you don't set any cursors, the 
default one (Allegro's for systems that don't have their own.. their can 
be a function to test this) is automatically set up. Then all you have 
to do is select which one of the pre-set cursor types you want to use. 
Any additional work that might happen would be done once at setup.

The latter also has the advantage of not needing to hijack 
set_mouse_sprite, since the hardware functions can call back onto that 
function if we're in a non-hardware mode. So really, we could rename 
set/select_hardware_cursor to set/select_mouse_cursor and have them 
behave the same not only between systems where their may or may not be a 
system cursor, but also on systems where there may or may not be a 
"hardware" cursor. Plus, set_mouse_cursor can be set up to return if the 
current system (eg. Windows in hardware mode) can accept the mouse 
cursor and allow the programmer to set something else if it can't 
(set_mouse_sprite doesn't have a return value, so there's no way to know 
if your mouse pointer was really set or not).

You could even have a few CURSOR_USER# types to make it easier to cycle 
through custom cursors (for animations or other uses).

- Kitty Cat