diff options
| -rw-r--r-- | background_scripts/settings.coffee | 2 | ||||
| -rw-r--r-- | content_scripts/scroller.coffee | 21 |
2 files changed, 17 insertions, 6 deletions
diff --git a/background_scripts/settings.coffee b/background_scripts/settings.coffee index f68a51d7..4a63a5fb 100644 --- a/background_scripts/settings.coffee +++ b/background_scripts/settings.coffee @@ -61,7 +61,7 @@ root.Settings = Settings = # or strings defaults: scrollStepSize: 60 - smoothScroll: false + smoothScroll: true keyMappings: "# Insert your prefered key mappings here." linkHintCharacters: "sadfjklewcmpgh" linkHintNumbers: "0123456789" diff --git a/content_scripts/scroller.coffee b/content_scripts/scroller.coffee index 27744116..0964a289 100644 --- a/content_scripts/scroller.coffee +++ b/content_scripts/scroller.coffee @@ -16,12 +16,18 @@ scrollProperties = viewSize: 'clientWidth' } +# Translate a scroll request into a number (which will be interpreted by `scrollBy` as a relative amount, or +# by `scrollTo` as an absolute amount). :direction must be "x" or "y". :amount may be either a number (in +# which case it is simply returned) or a string. If :amount is a string, then it is either "max" (meaning the +# height or width of element), or "viewSize". In both cases, we look up and return the requested amount, +# either in `element` or in `window`, as appropriate. getDimension = (el, direction, amount) -> if Utils.isString amount name = amount # the clientSizes of the body are the dimensions of the entire page, but the viewport should only be the # part visible through the window if name is 'viewSize' and el is document.body + # TODO(smblott) Should we not be returning the width/height of element, here? if direction is 'x' then window.innerWidth else window.innerHeight else el[scrollProperties[direction][name]] @@ -35,7 +41,7 @@ performScroll = (element, direction, amount) -> element[axisName] += amount element[axisName] == amount + before -# Test whether element should be scrolled. +# Test whether `element` should be scrolled. E.g. hidden elements should not be scrolled. shouldScroll = (element, direction) -> computedStyle = window.getComputedStyle(element) # Elements with `overflow: hidden` must not be scrolled. @@ -47,13 +53,15 @@ shouldScroll = (element, direction) -> # Test whether element does actually scroll in the direction required when asked to do so. Due to chrome bug # 110149, scrollHeight and clientHeight cannot be used to reliably determine whether an element will scroll. -# Instead, we scroll the element by 1 or -1 and see if it moved (then put it back). +# Instead, we scroll the element by 1 or -1 and see if it moved (then put it back). :factor is the factor by +# which :scrollBy and :scrollTo will later scale the scroll amount. :factor can be negative, so we need it +# here in order to decide whether we should test a forward scroll or a backward scroll. # Bug verified in Chrome 38.0.2125.104. doesScroll = (element, direction, amount, factor) -> # amount is treated as a relative amount, which is correct for relative scrolls. For absolute scrolls (only - # gg, G, and friends), amount can be either 'max' or zero. In the former case, we're definitely scrolling - # forwards, so any positive value will do for delta. In the latter, we're definitely scrolling backwards, - # so a delta of -1 will do. For absolute scrolls, factor is always 1. + # gg, G, and friends), amount can be either a string ("max" or "viewSize") or zero. In the former case, + # we're definitely scrolling forwards, so any positive value will do for delta. In the latter, we're + # definitely scrolling backwards, so a delta of -1 will do. For absolute scrolls, factor is always 1. delta = factor * getDimension(element, direction, amount) || -1 delta = Math.sign delta # 1 or -1 performScroll(element, direction, delta) and performScroll(element, direction, -delta) @@ -82,6 +90,8 @@ checkVisibility = (element) -> # continues scrolling at least until its keyup event is received. We never initiate a new animator on # keyboard repeat. +# CoreScroller contains the core function (scroll) and logic for relative scrolls. All scrolls are ultimately +# translated to relative scrolls. CoreScroller is not exported. CoreScroller = init: (frontendSettings) -> @settings = frontendSettings @@ -168,6 +178,7 @@ CoreScroller = # Launch animator. requestAnimationFrame animate +# Scroller contains the two main scroll functions (scrollBy and scrollTo) which are exported to clients. Scroller = init: (frontendSettings) -> handlerStack.push DOMActivate: -> activatedElement = event.target |