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");
19 define_variable("eye_guide_interval", 800,
20 "Interval during which the eye guide is visible (in ms). "+
21 "When 0, the eye guide will remain visible.");
23 define_variable("eye_guide_context_size", 50,
24 "Context size in pixels for eye-guide-scroll-down and "+
25 "eye-guide-scroll-up.");
27 define_variable("eye_guide_highlight_new", false,
28 "Highlight the new contents of the screen, instead of the old.");
30 function eye_guide_scroll (buffer, scroll_down, hl_new, context, interval) {
31 let win = buffer.focused_frame;
32 let doc = win.document;
33 let scroll_amount = win.innerHeight - context;
34 let old_y = win.scrollY;
35 win.scrollBy(0, scroll_down ? scroll_amount : -scroll_amount);
36 if (win.scrollY == old_y)
38 if (Math.abs(win.scrollY - old_y) < scroll_amount)
39 context = win.innerHeight - (scroll_down ? win.scrollY - old_y : old_y);
40 let guide = doc.getElementById("__conkeror_eye_guide");
42 guide = doc.createElementNS(XHTML_NS, "div");
43 guide.id = "__conkeror_eye_guide";
44 doc.documentElement.appendChild(guide);
47 guide.style.top = scroll_down ? context + "px" : "0px";
48 guide.style.height = (win.innerHeight - context) + "px";
50 guide.style.top = scroll_down ? "0px"
51 : (win.innerHeight - context) + "px";
52 guide.style.height = context + "px";
54 guide.style.display = "block";
56 "__conkeror_eye_guide_scroll_" + (scroll_down ? "down" : "up");
57 if (win.eye_guide_timer) {
58 win.clearTimeout(win.eye_guide_timer);
59 win.eye_guide_timer = null;
62 win.eye_guide_timer = win.setTimeout(
64 guide.style.display = "none";
70 interactive("eye-guide-scroll-down",
71 "Alternative to scroll-page-down, displays a guide to help "+
72 "your eyes follow the scroll.",
74 eye_guide_scroll(I.buffer, true, eye_guide_highlight_new,
75 eye_guide_context_size, eye_guide_interval);
78 interactive("eye-guide-scroll-up",
79 "Alternative to scroll-page-up, displays a guide to help "+
80 "your eyes follow the scroll.",
82 eye_guide_scroll(I.buffer, false, eye_guide_highlight_new,
83 eye_guide_context_size, eye_guide_interval);