The DualPlayField Facility

DualPlayField is a hardware facility in the Amiga computer by which there is not one but two graphics areas, in which the front one is transparent in its 'background' colour (pen 0). This allows two independent graphics fields to be registered with each other, one over the other, as though one was a sheet of glass in front on the main 'background' picture on which someone has drawn something. Moreover, the two can be scrolled and moved independently of each other, allowing one to 'slide over' the other. This facility is built into the video display hardware, and requires no special software or programming.

Yet it matches several high level requirements, of which the last is perhaps the most important and most exciting.

Thus the DualPlayField facility of the Amiga is no mere technical curiosity, but a fundamentally important feature that matches well a significant number of application requirements.

It could do with updating, e.g. to more colours per field and also to allow more than two fields sometimes. But most of the above applications require exactly two fields.


Copyright (c) Andrew Basden 1998.