[Oberon] Bluebottle, ETH Oberon / Aos 29.01.2003

[Thomas Frey]

> 2-
>  I played with W3dWorld stuff and wrote  a module about 3d rotation of
gears ( inspired from linux gl/gear.c).
>  Initialy, I used ReplaceObject() method of W3dWorld module; I create gear
object render it, then create a new
>  gear with different rotation matrix and replace it with th previous one
.......
>
>  This method seems fairly slow. So, instead of using ReplaceObject()
method, I thought that it would be
>  good if W3dWord.Object  exports  "vertices" and "nofVertices" fields,
then object vertices can be changed by
>  applying different matrices at runtime.
>  Then, custom W3dWorld module with these changes, programs works
continuously with high speed.
>
>  Is there any other method that vertices of object can be changed with the
program control.
>
> Could you add a method of changing the object vertices in W3*** modules in
the next versions.

Not much effort has been invested in W3d* it was only used for some simple
3d user interface experiments (about 1 week at all).
If W3d* is to be used for bigger applications, functions for scene graph
manipulations are needed. One object should be able to contain sub-objects
and each (sub-)object should have a object transformation matrix. The
implementation is quite simple but takes more time than I can currently
invest on it.

>  I can send the program module as a contribution If it is going to be
usefull.
Please do so, so I can have a look at it.

--Thomas