Initial import.

1 files changed, 169 insertions, 0 deletions

diff --git a/src/cmd/samterm/scroll.c b/src/cmd/samterm/scroll.c
new file mode 100644
index 00000000..994dc77f
--- /dev/null
+++ b/src/cmd/samterm/scroll.c
@@ -0,0 +1,169 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <thread.h>
+#include <mouse.h>
+#include <cursor.h>
+#include <keyboard.h>
+#include <frame.h>
+#include "flayer.h"
+#include "samterm.h"
+
+static Image *scrtmp;
+static Image *scrback;
+
+void
+scrtemps(void)
+{
+	int h;
+
+	if(scrtmp)
+		return;
+	if(screensize(0, &h) == 0)
+		h = 2048;
+	scrtmp = allocimage(display, Rect(0, 0, 32, h), screen->chan, 0, 0);
+	scrback = allocimage(display, Rect(0, 0, 32, h), screen->chan, 0, 0);
+	if(scrtmp==0 || scrback==0)
+		panic("scrtemps");
+}
+
+Rectangle
+scrpos(Rectangle r, long p0, long p1, long tot)
+{
+	Rectangle q;
+	int h;
+
+	q = r;
+	h = q.max.y-q.min.y;
+	if(tot == 0)
+		return q;
+	if(tot > 1024L*1024L)
+		tot>>=10, p0>>=10, p1>>=10;
+	if(p0 > 0)
+		q.min.y += h*p0/tot;
+	if(p1 < tot)
+		q.max.y -= h*(tot-p1)/tot;
+	if(q.max.y < q.min.y+2){
+		if(q.min.y+2 <= r.max.y)
+			q.max.y = q.min.y+2;
+		else
+			q.min.y = q.max.y-2;
+	}
+	return q;
+}
+
+void
+scrmark(Flayer *l, Rectangle r)
+{
+	r.max.x--;
+	if(rectclip(&r, l->scroll))
+		draw(l->f.b, r, l->f.cols[HIGH], nil, ZP);
+}
+
+void
+scrunmark(Flayer *l, Rectangle r)
+{
+	if(rectclip(&r, l->scroll))
+		draw(l->f.b, r, scrback, nil, Pt(0, r.min.y-l->scroll.min.y));
+}
+
+void
+scrdraw(Flayer *l, long tot)
+{
+	Rectangle r, r1, r2;
+	Image *b;
+
+	scrtemps();
+	if(l->f.b == 0)
+		panic("scrdraw");
+	r = l->scroll;
+	r1 = r;
+	if(l->visible == All){
+		b = scrtmp;
+		r1.min.x = 0;
+		r1.max.x = Dx(r);
+	}else
+		b = l->f.b;
+	r2 = scrpos(r1, l->origin, l->origin+l->f.nchars, tot);
+	if(!eqrect(r2, l->lastsr)){
+		l->lastsr = r2;
+		draw(b, r1, l->f.cols[BORD], nil, ZP);
+		draw(b, r2, l->f.cols[BACK], nil, r2.min);
+		r2 = r1;
+		r2.min.x = r2.max.x-1;
+		draw(b, r2, l->f.cols[BORD], nil, ZP);
+		if(b!=l->f.b)
+			draw(l->f.b, r, b, nil, r1.min);
+	}
+}
+
+void
+scroll(Flayer *l, int but)
+{
+	int in = 0, oin;
+	long tot = scrtotal(l);
+	Rectangle scr, r, s, rt;
+	int x, y, my, oy, h;
+	long p0;
+
+	s = l->scroll;
+	x = s.min.x+FLSCROLLWID/2;
+	scr = scrpos(l->scroll, l->origin, l->origin+l->f.nchars, tot);
+	r = scr;
+	y = scr.min.y;
+	my = mousep->xy.y;
+	draw(scrback, Rect(0,0,Dx(l->scroll), Dy(l->scroll)), l->f.b, nil, l->scroll.min);
+	do{
+		oin = in;
+		in = abs(x-mousep->xy.x)<=FLSCROLLWID/2;
+		if(oin && !in)
+			scrunmark(l, r);
+		if(in){
+			scrmark(l, r);
+			oy = y;
+			my = mousep->xy.y;
+			if(my < s.min.y)
+				my = s.min.y;
+			if(my >= s.max.y)
+				my = s.max.y;
+			if(!eqpt(mousep->xy, Pt(x, my)))
+				moveto(mousectl, Pt(x, my));
+			if(but == 1){
+				p0 = l->origin-frcharofpt(&l->f, Pt(s.max.x, my));
+				rt = scrpos(l->scroll, p0, p0+l->f.nchars, tot);
+				y = rt.min.y;
+			}else if(but == 2){
+				y = my;
+				if(y > s.max.y-2)
+					y = s.max.y-2;
+			}else if(but == 3){
+				p0 = l->origin+frcharofpt(&l->f, Pt(s.max.x, my));
+				rt = scrpos(l->scroll, p0, p0+l->f.nchars, tot);
+				y = rt.min.y;
+			}
+			if(y != oy){
+				scrunmark(l, r);
+				r = rectaddpt(scr, Pt(0, y-scr.min.y));
+				scrmark(l, r);
+			}
+		}
+	}while(button(but));
+	if(in){
+		h = s.max.y-s.min.y;
+		scrunmark(l, r);
+		p0 = 0;
+		if(but == 1)
+			p0 = (long)(my-s.min.y)/l->f.font->height+1;
+		else if(but == 2){
+			if(tot > 1024L*1024L)
+				p0 = ((tot>>10)*(y-s.min.y)/h)<<10;
+			else
+				p0 = tot*(y-s.min.y)/h;
+		}else if(but == 3){
+			p0 = l->origin+frcharofpt(&l->f, Pt(s.max.x, my));
+			if(p0 > tot)
+				p0 = tot;
+		}
+		scrorigin(l, but, p0);
+	}
+}