NEWLAYER(9.2) NEWLAYER(9.2) NAME newlayer, dellayer, lbitblt, lpoint, lrectf, lsegment, ltexture, upfront - layer control and graphics SYNOPSIS #include <jerq.h> Layer *newlayer(r); Rectangle r; void dellayer(l) Layer *l; void lbitblt(sl, r, dl, p, f) Layer *sl, *dl; Rectangle r; Point p; Code f; void lpoint(l, p, f) Layer *l; Point p; Code f; void lrectf(l, r, f) Layer *l; Rectangle r; Code f; void segment(l, p, q, f) Layer *l; Point p, q; Code f; void ltexture(l, r, t, f) Layer *l; Rectangle r; Texture *t; Code f; DESCRIPTION Newlayer creates a layer in Rectangle r in the physical dis- play bitmap, and returns its address, or 0 on failure. Newproc(9.2) explains how to attach a process to a layer. Dellayer de-allocates a layer; the associated process must also be freed (see newproc(9.2)). The routines lbitblt, lpoint, lsegment and ltexture are equivalent to their bitblt(9.3) counterparts except that they never inhibit the mouse cursor, so they are mainly use- ful only for implementation of efficient composite graphics operations such as circle-drawing. Because of the duality of Bitmaps and Layers, arguments of either type may be passed freely to any of the graphics primitives. SEE ALSO bitblt(9.3), newproc(9.2) Graphics in Overlapping Bitmap Layers, Rob Pike, ACM Trans. on Graphics, April 1983.