diff --git a/docs-mini/README.xmlpanel b/docs-mini/README.xmlpanel index 79d91759c..6019cc028 100644 --- a/docs-mini/README.xmlpanel +++ b/docs-mini/README.xmlpanel @@ -1,5 +1,5 @@ Users Guide to FlightGear panel configuration -Version 0.5, November 8 2000 +Version 0.6, March 1 2001 Author: John Check This document is an attempt to describe the configuration of @@ -124,10 +124,33 @@ applied *before* the transformation that describes the needle movement. About Textures: The texture files used to create the panel instruments are maximum 256x256 -pixels, red/green/blue/alpha format. When calling a section of a texture file -the 0,0 lower left convention is used. There is a pair of x /y coordinates -defining which section of the texture to use. +pixels, red/green/blue/alpha format. However the mechanism for specifying +texture cropping coordinates is decimal in nature. When calling a section +of a texture file the 0,0 lower left convention is used. +There is a pair of x/y coordinates defining which section of the texture +to use. +The following table can be used to calculate texture cropping specifications. + +# of divisions | width in pixels | decimal specification +per axis + 1 = 256 pixels 1 + 2 = 128 pixels, 0.5 + 4 = 64 pixels, 0.25 + 8 = 32 pixels, 0.125 + 16 = 16 pixels, 0.0625 + 32 = 8 pixels, 0.03125 + 64 = 4 pixels, 0.015625 + 128 = 2 pixels, 0.0078125 + +The recommended procedure for generating gauge faces is to use a +vector graphics package such as xfig, exporting the result as a +poscript file. 3D modeling tools may also be used and are prefered +for pretty items that don't require text such as levers, switches, +bezels and so forth. Ideally, the size of the item in the final render +should be of proportions that fit into the recommended pixel widths. +The resulting files should be imported into a graphics manipulation +package such as GIMP, et al for final processing. * If there are *any* XML parsing errors, the panel will fail to load, @@ -140,4 +163,3 @@ defining which section of the texture to use. there may also be built-in layers for special things like a weather-radar display or a GPS (though the GPS could be handled with text properties). -