2 * (C) Copyright 2009 John J. Foerch
4 * Use, modification, and distribution are subject to the terms specified in the
11 * require('eye-guide.js');
12 * define_key(content_buffer_normal_keymap, "space", "eye-guide-scroll-down");
13 * define_key(content_buffer_normal_keymap, "back_space", "eye-guide-scroll-up");
17 define_variable("eye_guide_interval", 800,
18 "Interval during which the eye guide is visible (in ms). "+
19 "When 0, the eye guide will remain visible.");
21 define_variable("eye_guide_context_size", 50,
22 "Context size in pixels for eye-guide-scroll-down and "+
23 "eye-guide-scroll-up.");
25 define_variable("eye_guide_highlight_new", false,
26 "Highlight the new contents of the screen, instead of the old.");
28 function eye_guide_scroll (buffer, scroll_down, hl_new, context, interval) {
29 let win = buffer.focused_frame;
30 let doc = win.document;
31 let scroll_amount = win.innerHeight - context;
32 let old_y = win.scrollY;
33 win.scrollBy(0, scroll_down ? scroll_amount : -scroll_amount);
34 if (win.scrollY == old_y)
36 if (Math.abs(win.scrollY - old_y) < scroll_amount)
37 context = win.innerHeight - (scroll_down ? win.scrollY - old_y : old_y);
38 let guide = doc.getElementById("__conkeror_eye_guide");
40 guide = doc.createElementNS(XHTML_NS, "div");
41 guide.id = "__conkeror_eye_guide";
42 doc.documentElement.appendChild(guide);
45 guide.style.top = scroll_down ? context + "px" : "0px";
46 guide.style.height = (win.innerHeight - context) + "px";
48 guide.style.top = scroll_down ? "0px"
49 : (win.innerHeight - context) + "px";
50 guide.style.height = context + "px";
52 guide.style.display = "block";
54 "__conkeror_eye_guide_scroll_" + (scroll_down ? "down" : "up");
55 if (win.eye_guide_timer) {
56 win.clearTimeout(win.eye_guide_timer);
57 win.eye_guide_timer = null;
60 win.eye_guide_timer = win.setTimeout(
62 guide.style.display = "none";
68 interactive("eye-guide-scroll-down",
69 "Alternative to scroll-page-down, displays a guide to help "+
70 "your eyes follow the scroll.",
72 eye_guide_scroll(I.buffer, true, eye_guide_highlight_new,
73 eye_guide_context_size, eye_guide_interval);
76 interactive("eye-guide-scroll-up",
77 "Alternative to scroll-page-up, displays a guide to help "+
78 "your eyes follow the scroll.",
80 eye_guide_scroll(I.buffer, false, eye_guide_highlight_new,
81 eye_guide_context_size, eye_guide_interval);