xref: /plan9/sys/src/cmd/samterm/scroll.c (revision ff8c3af2f44d95267f67219afa20ba82ff6cf7e4)
1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <thread.h>
5 #include <mouse.h>
6 #include <keyboard.h>
7 #include <frame.h>
8 #include "flayer.h"
9 #include "samterm.h"
10 
11 static Image *scrtmp;
12 static Image *scrback;
13 
14 void
15 scrtemps(void)
16 {
17 	int h;
18 
19 	if(scrtmp)
20 		return;
21 	if(screensize(0, &h) == 0)
22 		h = 2048;
23 	scrtmp = allocimage(display, Rect(0, 0, 32, h), screen->chan, 0, 0);
24 	scrback = allocimage(display, Rect(0, 0, 32, h), screen->chan, 0, 0);
25 	if(scrtmp==0 || scrback==0)
26 		panic("scrtemps");
27 }
28 
29 Rectangle
30 scrpos(Rectangle r, long p0, long p1, long tot)
31 {
32 	Rectangle q;
33 	int h;
34 
35 	q = r;
36 	h = q.max.y-q.min.y;
37 	if(tot == 0)
38 		return q;
39 	if(tot > 1024L*1024L)
40 		tot>>=10, p0>>=10, p1>>=10;
41 	if(p0 > 0)
42 		q.min.y += h*p0/tot;
43 	if(p1 < tot)
44 		q.max.y -= h*(tot-p1)/tot;
45 	if(q.max.y < q.min.y+2){
46 		if(q.min.y+2 <= r.max.y)
47 			q.max.y = q.min.y+2;
48 		else
49 			q.min.y = q.max.y-2;
50 	}
51 	return q;
52 }
53 
54 void
55 scrmark(Flayer *l, Rectangle r)
56 {
57 	r.max.x--;
58 	if(rectclip(&r, l->scroll))
59 		draw(l->f.b, r, l->f.cols[HIGH], nil, ZP);
60 }
61 
62 void
63 scrunmark(Flayer *l, Rectangle r)
64 {
65 	if(rectclip(&r, l->scroll))
66 		draw(l->f.b, r, scrback, nil, Pt(0, r.min.y-l->scroll.min.y));
67 }
68 
69 void
70 scrdraw(Flayer *l, long tot)
71 {
72 	Rectangle r, r1, r2;
73 	Image *b;
74 
75 	scrtemps();
76 	if(l->f.b == 0)
77 		panic("scrdraw");
78 	r = l->scroll;
79 	r1 = r;
80 	if(l->visible == All){
81 		b = scrtmp;
82 		r1.min.x = 0;
83 		r1.max.x = Dx(r);
84 	}else
85 		b = l->f.b;
86 	r2 = scrpos(r1, l->origin, l->origin+l->f.nchars, tot);
87 	if(!eqrect(r2, l->lastsr)){
88 		l->lastsr = r2;
89 		draw(b, r1, l->f.cols[BORD], nil, ZP);
90 		draw(b, r2, l->f.cols[BACK], nil, r2.min);
91 		r2 = r1;
92 		r2.min.x = r2.max.x-1;
93 		draw(b, r2, l->f.cols[BORD], nil, ZP);
94 		if(b!=l->f.b)
95 			draw(l->f.b, r, b, nil, r1.min);
96 	}
97 }
98 
99 void
100 scroll(Flayer *l, int but)
101 {
102 	int in = 0, oin;
103 	long tot = scrtotal(l);
104 	Rectangle scr, r, s, rt;
105 	int x, y, my, oy, h;
106 	long p0;
107 
108 	s = l->scroll;
109 	x = s.min.x+FLSCROLLWID/2;
110 	scr = scrpos(l->scroll, l->origin, l->origin+l->f.nchars, tot);
111 	r = scr;
112 	y = scr.min.y;
113 	my = mousep->xy.y;
114 	draw(scrback, Rect(0,0,Dx(l->scroll), Dy(l->scroll)), l->f.b, nil, l->scroll.min);
115 	do{
116 		oin = in;
117 		in = abs(x-mousep->xy.x)<=FLSCROLLWID/2;
118 		if(oin && !in)
119 			scrunmark(l, r);
120 		if(in){
121 			scrmark(l, r);
122 			oy = y;
123 			my = mousep->xy.y;
124 			if(my < s.min.y)
125 				my = s.min.y;
126 			if(my >= s.max.y)
127 				my = s.max.y;
128 			if(!eqpt(mousep->xy, Pt(x, my)))
129 				moveto(mousectl, Pt(x, my));
130 			if(but == 1){
131 				p0 = l->origin-frcharofpt(&l->f, Pt(s.max.x, my));
132 				rt = scrpos(l->scroll, p0, p0+l->f.nchars, tot);
133 				y = rt.min.y;
134 			}else if(but == 2){
135 				y = my;
136 				if(y > s.max.y-2)
137 					y = s.max.y-2;
138 			}else if(but == 3){
139 				p0 = l->origin+frcharofpt(&l->f, Pt(s.max.x, my));
140 				rt = scrpos(l->scroll, p0, p0+l->f.nchars, tot);
141 				y = rt.min.y;
142 			}
143 			if(y != oy){
144 				scrunmark(l, r);
145 				r = rectaddpt(scr, Pt(0, y-scr.min.y));
146 				scrmark(l, r);
147 			}
148 		}
149 	}while(button(but));
150 	if(in){
151 		h = s.max.y-s.min.y;
152 		scrunmark(l, r);
153 		p0 = 0;
154 		if(but == 1)
155 			p0 = (long)(my-s.min.y)/l->f.font->height+1;
156 		else if(but == 2){
157 			if(tot > 1024L*1024L)
158 				p0 = ((tot>>10)*(y-s.min.y)/h)<<10;
159 			else
160 				p0 = tot*(y-s.min.y)/h;
161 		}else if(but == 3){
162 			p0 = l->origin+frcharofpt(&l->f, Pt(s.max.x, my));
163 			if(p0 > tot)
164 				p0 = tot;
165 		}
166 		scrorigin(l, but, p0);
167 	}
168 }
169