Re: Emacs scrolling past the end of buffer

[Deniz Dogan <deniz@dogan.se>]

On 2012-02-09 11:06, Antoine Levitt wrote:
> 09/02/12 00:32, Deniz Dogan
>> On 2012-02-08 23:23, Antoine Levitt wrote:
>>> 08/02/12 22:21, Deniz Dogan
>>>> Hi,
>>>>
>>>> I've been trying to "fix" the behavior of ERC's scroll-to-bottom
>>>> module by hooking into erc-insert-post-hook.  I thought that the state
>>>> when that hook is executed would be that point is back in the input
>>>> area, but it does not seem like it.
>>>
>>> Hi,
>>>
>>> What's your plan for scroll-to-bottom in ERC? Why do you need this hook
>>> in addition to the existing one? scroll-to-bottom in its current state
>>> is clearly suboptimal, and it has a pretty excessive CPU consumption
>>> when repeating characters.
>>>
>>
>> I don't really have a fully thought-out plan yet, but I believe the
>> new hook is necessary, because the other hooks are run when the point
>> has moved away from its original position.  At least I couldn't figure
>> out how to write code that worked with those hooks.
>>
>> Having looked at the code for scroll-to-bottom just now, I see that it
>> uses post-command-hook, which is obviously not an acceptable solution
>> for the reason that you mention.
>>
>> A good compromise, in my opinion, would be to basically _not_ "scroll
>> to bottom" on every single character insertion.  With the addition of
>> the post-display hook, when the user hits RET, the message will be
>> sent, ERC will display that message, the new hook will run, and it
>> will be recentered to the bottom again.  This method is something I've
>> personally used in rcirc for quite some time and I'm very happy with
>> it.
>
> But then it sometimes happen that you see past the end of the buffer
> when scrolling (the horror!). I'd rather have excessive CPU consumption.
>

What if we combine this with a function in `window-scroll-functions'?  I 
haven't thought it through completely, but my gut feeling says it should 
be possible.