[PD] Gem screensizes

[IOhannes m zmoelnig]

marius schebella wrote:
> hi trevor,
> 
> 
>>I'm having a little trouble with screensizes in Gem - has anyone else
>>been through this already?
> 
> 
> yes. some problems could be caused by the graphic driver. i had a problems
> that squares looked like rectangles in fullsreen mode...

this sounds rather like a Gem-bug than a driver-problem.


> 
> 
>>Is there a function that can tell you the size of the window? Or are
>>there functions that link mouse-coordinates to object coordinates?

this is a bit of a problem, because mouse-coordinates and 
object-coordinates are *completely* different things.

imagine you are looking at a mountaineous landscape.
you can prove that two specific summits have a distance of 10 
centimeters, just because you have measured the distance with your 
fingers (~1m in fron of your head).
of course this is non-sense.

the same appies for Gem: object-coordinates refer to relations between 
objects in a scene, while mouse-coordinates (better: window-coordinates) 
refer to the projection of this scenery onto your screen.

> to convert mouse-coordinates(pixels) to "gem-coordinates" i use
> 
> [inlet] minus (windowsize in pixel / 2) minus 1 multiplied by 4
> 
> [inlet]
> |
> [/ 100] (screensize is 200)
> |
> [- 1]
> |
> [* 4]
> |
> [outlet]
> 

the cvs-version allows for normalized output of the window-coordinates.
[gemmouse 1 1] should give the mid-pixel as "0.5 0.5", no matter how the 
actual screen looks like.


> i don't know, if that is an official algorithm, it seems to work with sizes
> 200, 400, 600 but has some rounding errors with some other screensizes...

depends on the x/y-ratio. obviously, if you want a square to be a square 
with all window-dimensions, then you will have more space (e.g. need 
more translation to get out of the screen) in the x-direction if the 
screen is very wide.

> 
> 
>>Also (using Windows 98) when I maximise the Gem window, I can't get rid
>>of it again - even with Alt-Tab or by programming the patch to minimise
>>it again. Is there another way to do it?
> 
> 
> 
> how do you maximze? this should work, at least it does with XP... btw, there
> is also a "fullscreen 1" command. for fullscreen mode.

there are a lot of window-managers under linux that cannot handle this 
properly too: fullscreen-mode (with "fullscreen 1") will disable you to 
get any other window into the foreground. this is because of the 
no-border option, which tricks window-managers.
you will have to find another way to get control back, eg, by destroying 
the gem-window with a special click-combination.
if you want a big screen just use "dimen 1152x864" or whatever your 
screensize is (with borders turned on).
this should give you all control you want.

mfg.a.srd
IOhannes