ref: 023a0ce70099b0cc01c0956377def3238a6a947a
dir: /libmemlayer/line.c/
#include <u.h> #include <libc.h> #include <draw.h> #include <memdraw.h> #include <memlayer.h> struct Lline { Point p0; Point p1; Point delta; int end0; int end1; int radius; Point sp; Memlayer *dstlayer; Memimage *src; int op; }; static void llineop(Memimage*, Rectangle, Rectangle, void*, int); static void _memline(Memimage *dst, Point p0, Point p1, int end0, int end1, int radius, Memimage *src, Point sp, Rectangle clipr, int op) { Rectangle r; struct Lline ll; Point d; int srcclipped; Memlayer *dl; if(radius < 0) return; if(src->layer) /* can't draw line with layered source */ return; srcclipped = 0; Top: dl = dst->layer; if(dl == nil){ _memimageline(dst, p0, p1, end0, end1, radius, src, sp, clipr, op); return; } if(!srcclipped){ d = subpt(sp, p0); if(rectclip(&clipr, rectsubpt(src->clipr, d)) == 0) return; if((src->flags&Frepl)==0 && rectclip(&clipr, rectsubpt(src->r, d))==0) return; srcclipped = 1; } /* dst is known to be a layer */ p0.x += dl->delta.x; p0.y += dl->delta.y; p1.x += dl->delta.x; p1.y += dl->delta.y; clipr.min.x += dl->delta.x; clipr.min.y += dl->delta.y; clipr.max.x += dl->delta.x; clipr.max.y += dl->delta.y; if(dl->clear){ dst = dst->layer->screen->image; goto Top; } /* can't use sutherland-cohen clipping because lines are wide */ r = memlinebbox(p0, p1, end0, end1, radius); /* * r is now a bounding box for the line; * use it as a clipping rectangle for subdivision */ if(rectclip(&r, clipr) == 0) return; ll.p0 = p0; ll.p1 = p1; ll.end0 = end0; ll.end1 = end1; ll.sp = sp; ll.dstlayer = dst->layer; ll.src = src; ll.radius = radius; ll.delta = dl->delta; ll.op = op; _memlayerop(llineop, dst, r, r, &ll); } static void llineop(Memimage *dst, Rectangle screenr, Rectangle clipr, void *etc, int insave) { struct Lline *ll; Point p0, p1; USED(screenr.min.x); ll = etc; if(insave && ll->dstlayer->save==nil) return; if(!rectclip(&clipr, screenr)) return; if(insave){ p0 = subpt(ll->p0, ll->delta); p1 = subpt(ll->p1, ll->delta); clipr = rectsubpt(clipr, ll->delta); }else{ p0 = ll->p0; p1 = ll->p1; } _memline(dst, p0, p1, ll->end0, ll->end1, ll->radius, ll->src, ll->sp, clipr, ll->op); } void memline(Memimage *dst, Point p0, Point p1, int end0, int end1, int radius, Memimage *src, Point sp, int op) { _memline(dst, p0, p1, end0, end1, radius, src, sp, dst->clipr, op); }