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From: Reece Dunn (msclrhd_at_[hidden])
Date: 2004-12-15 14:00:29


Michael Walter wrote:
> Appendix: IIRC many of those small, home-brewn/hobby/amateur GUI
> libraries for OpenGL or stuff also support floating point coordinates.
> Interestingly enough, the GUI framework that comes with the DirectX
> SDK does *not* (possibly because the coordinates are in screen space
> -- is this what you necessarily want, though?).

As far as I can see, the DirectX framework uses a Device Context handle
(HDC) to draw contents to and a HDC uses integers to specify the
coordinate values. However, it has vectors and matrices that use float
values.

The mention of coordinates in screen space makes me see another
advantage of using floating point values: you can use them to store any
coordinate scale value, e.g. (10.45f, 2.77f) as centimeters on a page,
but this requires some coordinate conversion capabilities.

> On Wed, 15 Dec 2004 10:58:37 -0500, Michael Walter
> <michael.walter_at_[hidden]> wrote:
>
>>How about GUIs which simply support floating point coordinates
>>natively? I read that Cocoa uses floats for coordinates, and I would
>>wildly guess that Avalon will make use if float vectors, as well (at
>>least if the fancy 3D integration is remotely useful ;-).

Cocoa does indeed support float values natively.

Regards,
Reece


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