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Using Screen Captures Of Xscreensaver Modules For Image Sources

Date/Time Permalink: 01/06/12 03:51:43 pm
Category: Graphics Tutorials

A lot of people don't seem to know this, but you have a full library of image texture generators in your system's Xscreensaver library. The individual executables are in /usr/libexec/xscreensaver/.

Run any of the executables in the directory like this:

xscreensaver executable

...and then use Gimp's screenshot tool, single window, exclude window decoration (the titlebar). Now you can edit from there running filters on it, and see what you find. An example design taken from the demo shown above:

example 1

...after a few filter effects. Just to point out the possibilities. There's lots of things you can do here, if you explore the modules and find something with an interesting effect that comes in handy.

One problem is that the screensavers which use OpenGL may not lend well to being captured this way, depending on your hardware setup. On my laptop system, I get bad horizontal fracture lines, but on the desktop I don't.

Here's 'noof' with some glowy effects:

example 2

Here's 'xanalogTV', for the next time you need a quick generated image for a TV set on the fritz:

example 3

'Squiral' can generate some spiffy greeble textures for your next 3D model:

example 4

How I did the 'squiral' to greeble one: Screenshot 'squirral' when the window is almost full (right before it resets to a blank screen); edge-detect using the edge dialog at 'differential', 1.0, black; duplicate layer; desaturate 'average'; threshhold that black-and-white layer, moving the arrows to include or exclude as much detail as you want; go back to the color layer and map gradient (I used 'horizon 2'); go back to the black-and-white layer and gaussian blur it at about a 10.0, have the black-and-white below the color layer and bump-map the color layer using the black-and-white layer (adjust these parameters in the bump-map dialog to get the best effect). Sometimes you will get an unlucky shot and end up with white Xs over some of the squares, but otherwise, meh, it'll do from a distance.

Or if you're just seeking inspiration, you can run 'vidwhacker' to get a random surprise image from your home folder with a random filter run on it, capture it, and your challenge is to make it into something coherent.

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