GEM window properties:
This Chapter show how to go to fullscreen mode, (and leave it again) and how to setup the Gemwindow to work on the second screen.
Another options that we can perform with gemwin for example are killing the upper border, kill the macosX menubar and hide the mouse cursor over the gemwin (a must be for interactive installations..)
Most of the time, you have to deal first with your operating system before even opening pd...
While nothing is attached to the video output of the computer, the graphics card reserves for him all the performance, so usually you have to connect the vga/s-video cable or in some computers, like the new macs, you have to connect an "adaptor" (DVI-vga /DVI-composite..) to "inform" to the graphic card that you want to use the video output and then, your screen will turn black for one second (in case of osX) and now you are ready to go to the display preferences/ screen settings .. and turn on the second monitor, set the resolution and "extend desktop to that monitor" (in case of windows ) and set resolution and mirroring (on or off) in osX.
Note: Some times is better plug the video cable with the computer "off" an then start the computer in order to let the system recognize and adapt to the video output.
Mind that if we are using composite or s-video cable, resolutions greater than 720 x 576 are only going to cause trouble..
Also when you use DVI/Vga, the more resolution you use, less performance..
Apart of this things, When we want to use another screen or when we want to "project" the output of Gem, we are going to use at least two basical things: "fullscreen" and "offset".
in this patch we can see how it works..
Just mind that until you destroy and create the gemwin again, the changes in "fullscreen" or "offset" doesn´t take effect.
Offset it´s the amount of pixels that you have to displace the gem window. Tipically, you just need to displace the gem window in the X axis as much as the width pixels your screen has. (1024, 1280, 1440...). In the case of laptops, sometimes it´s required also to add a little bit of offset in the Y axis, Something like 20 or 40 should be enough...
Remember also that GEM it´s able to perform complex 3d things, so in addition to this basic setup objects, we can also set up a "lightning", a background color, a "camera position" and also fog!! ?!