separate out

src/libmemlayer/ldelete.c

@@ -0,0 +1,67 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <memdraw.h>
+#include <memlayer.h>
+
+void
+memldelete(Memimage *i)
+{
+	Memscreen *s;
+	Memlayer *l;
+
+	l = i->layer;
+	/* free backing store and disconnect refresh, to make pushback fast */
+	freememimage(l->save);
+	l->save = nil;
+	l->refreshptr = nil;
+	memltorear(i);
+
+	/* window is now the rearmost;  clean up screen structures and deallocate */
+	s = i->layer->screen;
+	if(s->fill){
+		i->clipr = i->r;
+		memdraw(i, i->r, s->fill, i->r.min, nil, i->r.min, S);
+	}
+	if(l->front){
+		l->front->layer->rear = nil;
+		s->rearmost = l->front;
+	}else{
+		s->frontmost = nil;
+		s->rearmost = nil;
+	}
+	free(l);
+	freememimage(i);
+}
+
+/*
+ * Just free the data structures, don't do graphics
+ */
+void
+memlfree(Memimage *i)
+{
+	Memlayer *l;
+
+	l = i->layer;
+	freememimage(l->save);
+	free(l);
+	freememimage(i);
+}
+
+void
+_memlsetclear(Memscreen *s)
+{
+	Memimage *i, *j;
+	Memlayer *l;
+
+	for(i=s->rearmost; i; i=i->layer->front){
+		l = i->layer;
+		l->clear = rectinrect(l->screenr, l->screen->image->clipr);
+		if(l->clear)
+			for(j=l->front; j; j=j->layer->front)
+				if(rectXrect(l->screenr, j->layer->screenr)){
+					l->clear = 0;
+					break;
+				}
+	}
+}