A Teaching Tool for Tablet PCs

YDraw is a free Drawing software authored by Ramesh Yerraballi. It is licensed under GNU Lesser General Public License v3.0

Installation

Download and Unzip YDraw-master.zip to any location. I suggest you unzip it to a folder called YDraw. YDraw will work on any system that has java 1.6 or later. All you need is a java runtime (from Oracle). The software is in the YDrawTool directory. You will find an executable jar file called YDraw.jar there.

Information

• What is YDraw?

  YDraw is a simple drawing software that can be used on a PC with a Touchscreen or a Mac with a Wacom tablet.

• Why YDraw?

  There are several drawing tools for Tablet computers and Wacom external tablets but they all have cumbersome GUIs that come in the way of writing. For example, if one wants to change the color of the pen one has to open a menu, scroll through it and pick the color. All this comes in the way and is captured if you are making a screencast. All YDraw options are keyboard shortcuts.

Running

Once you have the java runtime installed just double-click on the YDraw.jar file inside the YDrawTool directory that you unzipped in the previous step.

Usage

Note that all features in YDraw are accessible using keyboard shortcuts. So, all you will see is a blank screen when you run the jar. Nothing you checkpoint is ever lost as all sessions are automatically saved under the Saves folder where YDrawTool was installed.

• What/where are the options?

  There are a lot of options. Type Ctrl+h to find out.

• Use cases and Features:

• The properties file: There are a few customizable settings that one can set. You can configure these settings in the YDraw.properties file. Most properties there are self-explanatory, however if your screen captures are messed up (as in only a part of the screen or your grab) is actually being captured then its most likely that you are using Windows with a scaling. Most screens these days are of such high resolution that windows automatically scales its pixels (by default of 200%). Most applications pick up this information but the java vm does not. We need to help it by telling it what scaling is by the property ScreenScaling. If your screen is at 200% then you will set this property to 2.
• Hotkeys :
  • Thickness - To change the thichness of the pen you can either choose from four preset thickness (extrafine, Fine, thick and extraThick). Alternatively, you can use the up and down arrow keys to change the thickness of the pen at a finer granularity.
  • Color - The color hotkeys are as follows: blue (default), white, Black, red, green, magenta, orange. maRoon, cyan, yellow, orange. Try the a key for a random color. Also, uppercase on these hotkeys gives a darker version of the same color
  • Eraser - The eraser can be engaged several ways, the simplest way is to use the top end of the stylus. Alternatively, you can press the button on the stylus while you write. If you want to use it continuously then simple use the hotkey erase
  • Dashed line - Use the dash hotkey if you want your lines to be dashes.
  • Highlighter - Use the Ctrl+m hotkey to mark things using a highlighter. The color of the highligher can be configured in the properties file.
• Recording a session: The notion of a session is screenshots taken at key points in ones narrative which can then be saved. At points where one has covered something of substance and may move to a different concept one can save a checkpoint (Ctrl+p). One can navigate through the checkpoints using (Ctrl+r or Ctrl+left to rewind and Ctrl+f or Ctrl+right to forward). When you are done, you can save all the checkpoints by using Ctrl+x to quit, which saves all the checkpoints as png files and creates a PDF document. The png files are higher quality than the PDF document. Resuming a session: One can preload a previous session using Ctrl+l. You do this if you want to review what you covered in the previous session and/or use that as a starting point for the current session.
• Cut-and-paste from Clipboard: Anything in the clipboard (text or images) can be brought into YDraw by using Ctrl+v as you do in any other application. So, if you cut some text in say a document then you can paste it in YDraw. If the font is too small, undo the paste (Ctrl+z) and then use the right arrow key to make the font bigger and paste again. If you paste a image then you can scale it up or down using the ">" or "<" key (no need to undo the paste).
• Grab content from YDraw: To grab content from YDraw use Ctrl+g and then choose the rectangular region you want to grab (a gray outline will show you that that region has been copied. You now have that region in your Clipboard. You can paste it if any application that allows you to paste (Ctrl+v)an image from the clipboard.
• Image Presets: You can pre-populate Ydraw with up to 10 images that can then be imported into YDraw with a single key(number 0-9). The images you want to preset have to be stored in the images directory in the YDrawtool folder. The image files can be gif, png or jpg, named in lexical order. The lower named file gets assigned the lower number hotkey with the lowest one getting hotkey 0. The import always happens where the cursor is currently located. If you disable the mouse then the pen position is the cursor position. If you don't like where the import occurred then simply undo (Ctrl+z) the paste and move the cursor where you want the import and press the number hotkey again.
• Using as a Glass: If you have some other application under YDraw that you'd like to draw on. You can engage the YDraw glass feature using Ctrl+t which makes YDraw transparent. You can then take a snapshot of the screen, which will be the appication snapshot. Now disable the glass feature by using Ctrl+t again. Now you can go back to the last snapshot using Ctrl+r (rewind) and start writing on it. Also, when you are in the "glass" feature you can change the transparency of YDraw by using PgUp and PgDn keys. Use this to annotate directly on the bottom application (of course you can still take a snapshot of that) Another neat thing you can do with the glass feature is to grab just section of the bottom application. For example if there is code(insides an IDE or browser etc.) you want to import into YDraw with its color scheme in place use Ctrl+t followed by Ctrl+g and you have the section in your clipboard.
• Quit or Exit : There are two ways the terminate your session. Use Ctrl+q if you want to quit without saving explicitly. Note that all sessions (individual snapshots) are still auto-saved in the saves folder. To end a session and have a PDF document of the session, use Ctrl+x, which prompts you for a destination folder to save your session in.
• The Khan Academy mode: If you are presenting in a room that has too much light you can use the reverse video mode akin to the mode used by Salman Khan in his Khan Academy videos. Engage this mode using Ctrl+b. I like using this mode when I am recording a screencast
• One screenshot: To save a single screenshot to a destination folder use Ctrl+s. I use this during my office hours to explain something to a student and then mail the screenshot to her.

Acknowledgements:

1. Uses the LGPL licensed freeware JPen (http://sourceforge.net/projects/jpen/) as the engine on top of which the tool is built. JPen itself is unmodified.

2. Uses the AGPL licensed iText to generate PDFs (http://www.itextpdf.com/)