EmacSide

Exploring the IDE side of Emacs.

Table of Contents

• EmacSide
  • Overview
  • Editing articles
    • Adding a category
    • Adding a solution to an existing article
• Videos
  • Record screencast
    • Open Emacs
    • Set right emacs window size
    • Big mouse cursor
    • Show keystrokes
      • Current Configuration
    • Recording screen
  • Post processing
    • Convert ogv to avi
    • Cut any undesired part from the beginning or end
  • Titles of solutions
  • Annotate in screen during video
    • Install
    • To draw on screen
  • Locate mouse pointer
  • Emacs Logo for videos
    • Shortcut keys
  • Contribute

Overview

Set of common developers use cases and how to solve them in Emacs.

Editing articles

The correct way to add a keystroke combination is:

<kbd><kbd>M</kbd>+<kbd>s</kbd> <kbd>o</kbd></kbd> for M+s o.

Source: w3 kbd element.

For an Emacs command with its keystrokes and description we use the Bootstrap 4 alert classes:

**next-error-follow-minor-mode** <kbd><kbd>C</kbd>-<kbd>c</kbd> <kbd>C</kbd>-<kbd>f</kbd></kbd>
: Minor mode for compilation, occur and diff modes.
{: class="alert alert-info"}

Adding a category

New categories should be added to _data/nav.yml in the categories/subcategories section, e.g. for adding the navigation section:

documents:
  ...
  subcategories:
    url: /navigation
    name: Navigation

Then add to the folder /_documents

• a new file /_documents/navigation.html

---
layout: document_category
---

• a new folder /_documents/navigation.

Adding a solution to an existing article

You can add your specific solution to any article

Then add also your personal information and it will be credited to you in the article as the author owner.

1. Add yourself to the author list _data/people.yml.
2. Add a solution to the right folder in the _documents directory inside the folder of the same article name.

Videos

Videos are in playlist mode in the main article and each particular video has a special page.

Record screencast

Open Emacs

$ emacs --name="EmacSide.com"

More: Emacs window size

Set right emacs window size

Select the Emacs window and resize.

Video size: 16:9 original aspect ratio (1280x720 recommended).

wmctrl -r EmacSide.com -e 0,1,1,1280,720
wmctrl -r EmacSide.com -e 0,1,1,1000,562.5

Big mouse cursor

sudo apt-get install dconf-tools

$ dconf-editor
#### or directly
$ dconf write /org/gnome/desktop/interface/cursor-size 48

Show keystrokes

Open screenkey.

$ screenkey

Select Emacs window.

Current Configuration

• Time: 2
• Position:
  • Screen 0:None
  • position: bottom
• Aspect
  • Font: Sans Bold
  • Size: medium
  • Font color:
  • Opacity: 0.7
• Keys
  • Keyboard mode: composed
  • Backspace mode: baked
  • Modifiers mode: emacs
  • NO Show Modifier sequences only
  • YES Always show Shift
  • YES Show Whitespace characters
  • YES Compress repeats after 2

Recording screen

List windows names

$ wmctrl -l

And insert the Emacs window id like 0xFFFFFFF.

$ recordmydesktop --output=out.ogv --windowid 0xFFFFFFF

Automatically:

$ recordmydesktop --windowid `wmctrl -l | grep "EmacSide.com" | col1

or

$ gtk-recordmydesktop

Generates ~/out.ogv file.

Post processing

Convert ogv to avi

$ avconv -i writeroom-mode.ogv -b:v 1000K -q:v 1 -c:v libx264 out.avi

If you don't specify a bitrate for the video, it will choose the mpeg4 video encoder for the MKV container. It uses a default of 200 kBit/s, which is low, hence the visual artifacts. If you want to increase the quality, you have three options: Choose a higher bitrate (e.g. -b:v 1000K) Choose variable quality (e.g. -q:v 1). Lower means better. Good values are between 1 and 4. Choose a higher quality video codec, e.g. H.264 (-c:v libx264) and set the CRF for quality (e.g. -crf 23). Lower means better, and sane values are between 18 and 28.

Cut any undesired part from the beginning or end

ffmpeg -i input.wmv -ss 00:00:30.0 -c copy -t 00:00:10.0 output.wmv

May use them while recording:

;;Highlight current line only in this buffer
;;(hl-line-mode)

Titles of solutions

Youtube cut titles at 53 char approx. and the recommended title length is 70. Try to keep the titles length below the 53 chars mark.

Annotate in screen during video

Install

sudo apt-get install gromit gromit-mpx

To draw on screen

Press Pause button and start drawing.

Project homepage.

$ gromit-mpx

Locate mouse pointer

Show the mouse pointer with locate-pointer.

Current keybinding: Super+M.

Emacs Logo for videos

Generated with jp2a - JPEG to ASCII image converter.

Shortcut keys

Pause: toggle painting Shift-Pause: clear screen CTRL-Pause: toggle visibility

ALT-F9: Quit Gromit-MPX. F10: undo last stroke SHIFT-F10: redo last undone stroke

Contribute

Any contribution is very welcome.