From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: nljlistbox2@gmail.com (N. Jackson) Newsgroups: gmane.emacs.help Subject: Re: How to scroll images in Emacs? Date: Thu, 20 Feb 2014 00:20:08 -0400 Organization: Aioe.org NNTP Server Message-ID: <8761oah0uf.fsf@moondust.localdomain> References: <87eh32llk9.fsf@moondust.localdomain> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1392870311 21861 80.91.229.3 (20 Feb 2014 04:25:11 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 20 Feb 2014 04:25:11 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Thu Feb 20 05:25:21 2014 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WGLCJ-0007ci-86 for geh-help-gnu-emacs@m.gmane.org; Thu, 20 Feb 2014 05:25:19 +0100 Original-Received: from localhost ([::1]:36105 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WGLCI-0006Pp-K0 for geh-help-gnu-emacs@m.gmane.org; Wed, 19 Feb 2014 23:25:18 -0500 Original-Path: usenet.stanford.edu!goblin1!goblin2!goblin.stu.neva.ru!aioe.org!.POSTED!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 135 Original-NNTP-Posting-Host: A/aOcvrYi8h0Dz5xhehW6g.user.speranza.aioe.org Original-X-Complaints-To: abuse@aioe.org User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3.50 (gnu/linux) X-Notice: Filtered by postfilter v. 0.8.2 Cancel-Lock: sha1:w0DxeQXsKVAzmdGXP3QIIgO6sSw= Original-Xref: usenet.stanford.edu gnu.emacs.help:203864 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:96132 Archived-At: At 01:04 -0400 on Monday 2014-02-17, Eli Zaretskii wrote: >> From: nljlistbox2@gmail.com (N. Jackson) >> Date: Sun, 16 Feb 2014 18:49:58 -0400 >> >> I'm not used to having images in Emacs, and I'm having difficulty >> understanding their scrolling behaviour. >> >> I can't seem to scroll them horizontally at all, and when I scroll them >> vertically, as soon as the top edge of the image hits the top of the >> window, the whole image jumps up completely out of view. This makes it >> very hard to veiw the bottom portion of an image, although sometimes I >> can sneak up on it from below. Often, however, the window then scrolls >> back up to the top of the image. >> [...] >> Using GNU Emacs 24.3.50 of 2014-02-10. > > These problems shouldn't exist in the development version. With > yesterday's trunk, I can scroll images both horizontally and > vertically, using just the arrow keys, and there are no jumps that you > describe. > > If it doesn't work for you in "emacs -Q", please submit a bug report > using "M-x report-emacs-bug RET", starting with "emacs -Q", and > include the image that gives you this trouble. > > Thanks. I am now running GNU Emacs 24.3.50 (x86_64-unknown-linux-gnu, GTK+ Version 3.8.8) of 2014-02-19 Repository revision: 116484 lekktu@gmail.com-20140219210406-y2s7lx244ojfl5on. I am still having several "issues", some of which are clearly bugs, but some of which might simply be that I don't understand the intended behaviour. Should I report separate bugs for Image mode, Eww, Gnus, and the frame resizing? A. An image in Image mode ========================= emacs -Q C-x C-f ~/my-image.jpg Note: This test image is larger than the display I am using. 1. The top left of image image is displayed. Scrolling with arrow keys works properly and smoothly left/right up/down. But scroll bars don't work. Vertical scroll bar jumps back to top whenever it's pulled down. Horizontal scroll bar is missing entirely from window. 2. There is no menu option for resizing image to the window. Is there a command for this? 3. M-x image-transform-fit-to-width has no effect, but no error is written to the *Messages* buffer. (Note: My build includes ImageMagick support. Is this perhaps disabled with "emacs -Q"?) 4. The menu option "Fit Frame to Image" does not work properly. The frame increases in size to _almost_ fill the display, but there is a gap of a few pixels along the left side and along the bottom, and the top of the window is about one title-bar-width below the top of the display. Furthermore, the system doesn't seem to know how big the window is, because if I now maximise the frame (with the logo key and the up arrow) and restore it again (with the logo key and the down arrow), it "restores" to another size that is smaller than the size after the "Fit Frame to Image" command, but not nearly as small as the original size when Emacs started. (I think I read a bug report a month or two ago of similar behaviour, but not with Image mode?) B. An image in Eew ================== emacs -Q M-x eww (enter "www.gnu.org/distros/screenshot.html" at the prompt) A page loads with a screenshot about half way down. B.1. Jerky scrolling: Scroll down page with down arrow key, one press at a time. When the cursor gets to the line above the screenshot, the image starts scrolling smoothly upwards with each press of the arrow key, but the cursor itself stays on the line above the image which seems wrong. If the cursor is on a line and I press the down arrow key, I expect the cursor to now be on whatever is below that line. At some point (possibly when the image has risen high enough to clear the bottom edge of the window) the cursor jumps to the right edge of the image (at least I can see a line flashing there as if it were the cursor). When this shift happens there is a sudden (small) jump in the image that is not at all smooth. One more down arrow press moves the cursor to the line below the image. This seems correct, and the cursor continues to descend the page. But then the page suddenly scrolls, making the image suddenly disappear, rather than smoothly scrolling up out of sight. If I now scroll back up the page by pressing the up arrow key, one press at a time, at no point does the image scroll smoothly -- it just jerks downwards in two big jumps. B.2. No horizontal scrolling: I maximise the frame (logo key and up arrow), then reload the page. The image is now much larger. I now restore the page (loge key and down arrow). I now have only the left edge of the image in the window, which is fine. The problem is there is no horizontal scroll bar, and the image won't scroll with the arrow keys. C. An image in Gnus =================== This is not from emacs -Q because I can't seem to run Gnus that way (no gnutls?). The image is an attachment in an email. (It's actually the same JPEG as in A. above.) The top left of the image is displayed. Scrolling down the email with the down arrow key, the image scrolls smoothly until just after the bottom edge appears at the bottom of the window, then it jumps completely up out of view. Scrolling back up again, when the image first appears, it does so in a jerky motion in which the bottom maybe 1/4 of the image all appears at once, then, on most attempts it scrolls smoothly upwards. However, a few times it "glitches" and the image, after scrolling fine for a bit, suddenly jumps back to the position at which it first appeared when scrolling up, with the bottom maybe 1/4 of the image showing in the window. There is no horizontal scroll bar, and the cursor keys don't seem to scroll the image horizontally.