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Color attributes
Internal Images

Internal Images

At the location /internal-roxen-* in your webserver you'll find some images which are always available to be included in image tags and the like.


One commonly used image is /internal-roxen-unit which is a 1x1 pixel transparent GIF image. Small transparent images are often used by HTML layout designers to create spaces between other elements.


At the location /internal-roxen-pixel-color you'll find a 1x1 non-transparent pixel in the selected color. Examples are /internal-roxen-pixel-blue or /internal-roxen-pixel-ff34c0. The colors are decoded as describe in Color attributes, though not all syntax variants are applicable to URLs (for instance, leave out # for the RGB format as seen in the example earlier).


Similarly, by requesting /internal-roxen-spinner-color you will get an animated GIF image that spins indefinitely with the provided color as the background color. For example, /internal-roxen-spinner-blue or /internal-roxen-spinner-ff34c0.

Bitmap Files

All images that reside in the directory server/roxen-images in your Roxen WebServer distribution is available through /internal-roxen-*. All the images available in the server/roxen-images/dir directory is available through /internal-gopher-*. E.g. if you want to put the image help.gif on your page, just use <img src="/internal-roxen-help" />. Note that the look of the images as well as the contents of server/roxen-images may vary.

The following images will always exist with the same look and size:




The following images will always exist, but may change in appearence.












Color selector

In order to easily create a multistage color selection widget you can acces automatically generated saturation bars through the /internal-roxen-colorbar URL. /internal-roxen-colorbar:h,b,w returns a 30x256 pixels big color bar with the hue h,the brightness b and a white marker at the location w, 0 being the bottom and 255 the top. The interval for all three variables are 0-255. The intended use is to first present the user with a two-dimensional hue/brightness selector, as shown above. The selected combination is then used as basis for which colorbar to show, where the user can selected the preferred saturation.

<for variable="var.i" from="0" to="255" step="24"> <img border="1" src="/internal-roxen-colorbar:&var.i;,255,&var.i;" /> </for>

The code above will generate the 11 colorbars shown below. All of them has brighness set to 255, but their hue will range from 0 to 255 in with steps of 24.