Re: [Super-tux-devel] Gameloop Rewrite Status

[Ricardo C. <ri...@ae...>]

Hey there!

 Nice to see that the gameloop is being worked, since here is where the act=
ion=20
takes place.
 I've already done a collision func to test collisions between two surfaces=
,=20
but I am sure this is not the right way to go.  What I do is to check if=20
there are pixels from both images that are different from the colorkey and=
=20
that are in the same position.
(since supertux uses the alpha bit, you would had to replace colorkey by=20
alpha).
 However, this method is slow and I think that it is unnecessary in this ga=
me.=20
a better approach would be the use of a bitmask per surface, as explained a=
nd=20
implemented over here:
http://www.ifm.liu.se/~ulfek/projects/2d_Collision_Detection.html

Ricardo

Em Sexta, 2 de Janeiro de 2004 23:04, o Tobias Gl=C3=A4=C3=9Fer escreveu:
> Hi all,
>
> I'm making progress and you'll probably see the next CVS commit
> tonight. I'm currently thinking about the new collision detection
> and decided to move them all into one place. (i.e. collision.c/h ?)
> We need a function, wich can do collision detection, but there are many
> possibilities on how to do this.
>
> One possibility is to check if the "rectangle" of an object hits the
> "rectangle" of another object, like we currently do, but I don't like
> this method, because it isn't very precise. On the other hand it's
> relativly fast.
>
> The other way to do collision detection would be a pixel-per-pixel
> solution, where we test, if two non-alpha pixels hit each other.
> Maybe someone has already written such a function or a class in C++,
> which could be ported.
>
> My experience in this area is low (tux bless google), but I guess
> some of you have experience and can give me some hints and tips. :)
>
> Greetz...
>
> Tobias Gl=C3=A4=C3=9Fer

=2D-=20
"Hi.  This is Dan Cassidy's answering machine.  Please leave your name and=
=20
number... and after I've doctored the tape, your message will implicate you
 in a federal crime and be brought to the attention of the F.B.I... BEEEP"
 -- Blue Devil comics