a

libmemlayer/ltofront.c

@@ -0,0 +1,80 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <memdraw.h>
+#include <memlayer.h>
+
+/*
+ * Pull i towards top of screen, just behind front
+*/
+static
+void
+_memltofront(Memimage *i, Memimage *front, int fill)
+{
+	Memlayer *l;
+	Memscreen *s;
+	Memimage *f, *ff, *rr;
+	Rectangle x;
+	int overlap;
+
+	l = i->layer;
+	s = l->screen;
+	while(l->front != front){
+		f = l->front;
+		x = l->screenr;
+		overlap = rectclip(&x, f->layer->screenr);
+		if(overlap){
+			memlhide(f, x);
+			f->layer->clear = 0;
+		}
+		/* swap l and f in screen's list */
+		ff = f->layer->front;
+		rr = l->rear;
+		if(ff == nil)
+			s->frontmost = i;
+		else
+			ff->layer->rear = i;
+		if(rr == nil)
+			s->rearmost = f;
+		else
+			rr->layer->front = f;
+		l->front = ff;
+		l->rear = f;
+		f->layer->front = i;
+		f->layer->rear = rr;
+		if(overlap && fill)
+			memlexpose(i, x);
+	}
+}
+
+void
+_memltofrontfill(Memimage *i, int fill)
+{
+	_memltofront(i, nil, fill);
+	_memlsetclear(i->layer->screen);
+}
+
+void
+memltofront(Memimage *i)
+{
+	_memltofront(i, nil, 1);
+	_memlsetclear(i->layer->screen);
+}
+
+void
+memltofrontn(Memimage **ip, int n)
+{
+	Memimage *i, *front;
+	Memscreen *s;
+
+	if(n == 0)
+		return;
+	front = nil;
+	while(--n >= 0){
+		i = *ip++;
+		_memltofront(i, front, 1);
+		front = i;
+	}
+	s = front->layer->screen;
+	_memlsetclear(s);
+}