draw-bezier-curve

Arguments: stream vertices

The function was named draw-curve is releases prior to 8.0. The new name is more descriptive and less likely to conflict with a user function name. The behavior has not changed.

Draws one or more Bezier curves on stream. vertices should be a sequence (list or vector) of positions (see make-position) that indicate the starting, ending, and control points for the curves. Each curve is specified by four positions that indicate a starting point, two control points, and an ending point in that order. The ending point of each curve is re-used as the starting point of the next curve, and so vertices must contain (1+ (* 3 N)) to draw N curves (where N must be at least 1). For example, to draw two connected curves you need to pass a sequence of 7 positions, where positions 1 through 4 specify the first curve and positions 4 through 7 specify the second.

stream should be a cg-stream.

See also cg-drawing.htm.

GTK Note

This function is not implemented on the GTK platform. It is probably not feasible to implement it in CG without a GTK hook into the display adapter's functionality for doing the drawing with adequate speed. Calling the function on GTK will simply invoke the *gtk-compatibility-warning-action*.

Copyright (c) 1998-2009, Franz Inc. Oakland, CA., USA. All rights reserved.
Documentation for Allegro CL version 8.1. This page was not revised from the 8.0 page.
Created 2009.7.29.