=====Displaying inverse video=====

 Inverse video is a display mode where text and graphics on a display are presented as a negative of their original appearance.\\ \\ 
==== Inverse Video Text ====
//by Jon Ripley, May 2006//\\ \\  To read the current foreground and background text colours use the following code:

<code bb4w>
        fgcol% = @vdu%?70
        bgcol% = @vdu%?71
</code>

Here **fgcol%** and **bgcol%** are normalised values in the range 0 to 15 representing the logical colour used.\\ \\  To invert the colours of the text display use the following code:

<code bb4w>
        COLOUR bgcol%
        COLOUR 128+fgcol%
</code>

Now any text you **PRINT** will be in inverse video.\\ \\  To restore the original foreground and background text colours use the following code:

<code bb4w>
        COLOUR fgcol%
        COLOUR 128+bgcol%
</code>

==== Inverting the whole window ====
//by Richard Russell, May 2006//\\ \\  You can invert all the existing colours in the output window (or in the graphics viewport, if one is defined) as follows:

<code bb4w>
        GCOL 4,128
        CLG
</code>

This will affect both text and graphics. Executing this code twice will restore the original colours.