Column interlacing is a feature of the c2p system that allows you to distribute the refresh of a display amongst more than one frame. A `column' refers to a column of 32 pixels in width, the height of the c2pWindow. Depending on wether the system is handling the odd or even columns, every other column will be skipped so that even columns are converted in one call and the odd columns are converted in the second call. The odd/even frames should be toggled inbetween these two calls (see the `Mc2pToggle' type commands).

Note that column interlacing will only give the impression of an increase in framerate but does not magically perform a c2p conversion twice as fast, and using the extra time for extra processing will still reduce the framerate.

Mc2pColumnLacing allows you to switch column-type interlacing in the chunky-to-planar routines On or Off. When Mc2pColumnLacing is switched On, all following calls to Mc2pWindow will produce different data internally so that when you perform Mc2p to convert the chunky data to planar the correct line modulos will be in place to make the column-interlacing work.

You should be careful to use Mc2pWindow after having switched column interlacing on, otherwise the system will not work as desired. When column interlacing is active, any c2pWindows that you create will contain different data than if column lacing were inactive, so you cannot mix the two.

Calling Mc2pColumnLacing resets the current column-lace frame to `even' columns, and there is nothing to prevent you using it for this purpose.

Possible syntax:
Mc2pColumnLacing Status.b


Status.b ---- This parameter switches the column interlacing status On or Off. Generally you can pass to it the `On', `Off', `True' or `False' keywords, or alternatively 0 means off and any other value means on.