Doodle

Doodle is a compact paint application for the U S Robotics Pilot. Doodle implements multiple pens, multiple inks, and multiple pages in a little less than 5400 bytes of memory. Each page saved in the database occupies another 3200 bytes of memory. Pen strokes in the drawing area of Doodle are translated into drawing. Characters written in the graffiti area are translated into commands. The commands can also be found in the menus. The Pilot scroll buttons may also be used to switch between pages.

• Download Doodle 0.6
• Download Source 0.6
• Download Doodle 0.2
• Download Source 0.2
• Doodle Command Summary
• New Features
• Quirks, Bugs, Whatever
• Background
• Use the Source, ...

Doodle Command Summary

Menu	Char	Item	Description
Page
	C	Clear	Clear the visible part of the current screen.
	F	Fill	Fill the visible part of current screen with the current ink.
	N	New	Create a new page.
	D	Duplicate	Duplicate the current page onto a new page.
	R	Remove	Remove the current page.
	T	Title	Toggle the display of the Doodle title bar on or off.
	-	Previous	Page up to the previous screen
	+	Next	Page down to the next screen
	A	About	Display the copyright.
Mode
	P	Paint	Paint with the current pen and ink.
	S	Smear	Smear with the current pen.
	E	Erase	Erase with the current pen.
	<	Unsmooth	Draw unsmoothed pen events.
	=	Smooth	Smooth pen events in groups of four.
	>	Smoother	Smooth pen events in groups of eight.
Pen
	.	Fine	A one by one.
	·	Medium	A two by two. Graffiti extended-shift dot.
	@	Broad	A five by five hollow.
	,	F. Italic	A four pixel italic.
	/	M. Italic	An eight pixel italic.
	;	B. Italic	A twelve pixel italic.
Ink
	0	White	White.
	1	1/8th	12.5% grey.
	2	2/8th	25.0% grey.
	3	3/8th	37.5% grey.
	4	4/8th	50.0% grey.
	5	5/8th	62.5% grey.
	6	6/8th	75.0% grey.
	7	7/8th	87.5% grey.
	8	Black	Black.
	9	Shuffle	Shuffle the bits of the current ink using the bits of the current ink as the random number seed.
None
	Previous	Button	Page up to the previous screen
	Next	Button	Page down to the next screen

New Features

Doodle 0.6 released April 26, 1997. Versions 0.3, 0.4, and 0.5 were never released.

• The drawing mode, filtering, pen nib, and ink stipple are displayed as buttons on the title bar along with the page number and graffiti state indicator. Tapping on a button will advance to the next mode, filter, nib, ink, or page.
• The 2/8, 3/8, 5/8, and 6/8 stipples have been redone to eliminate stripes.
• Using the command shift to Clear or Fill no longer leaves a rectangle behind.
• Two degrees of pen smoothing have been implemented to reduce jaggies.
• Page flipping can be done via the menu and command characters as well as the scroll buttons
• Page flipping treats the database as a circular buffer.
• The Broad pen is square instead of rectangular.
• There is a Duplicate command which creates a copy of the current page for you to mess up.
• The Remove command removes the current page and decrements the current page index.
• Erase mode uses white ink with the current pen, but leaves the current ink in place when you return to Paint mode.
• The doodle database, DoodleDB.pdb, is backed up by HotSync.
• The source distribution includes a program, doodle-db.c which splits DoodleDB into PBM bit map files or assembles a DoodleDB from PBM bit map files.

Quirks, Bugs, Whatever

• There is a report that the recently released PalmOS 2.01 update crashes Doodle 0.2 utterly. Please let me know if Doodle 0.6 suffers the same fate.
• If you turn off the title bar with T and clear the screen, it may be hard to tell if your Pilot is on or off by looking at it.
• The Clear and Fill commands only operate on the visible portion of the page. If the title bar is displayed, then there's a strip off the bottom of the screen which won't be modified.
• Under some situations, the doodle screen may capture a displayed menu or the application icon screen. If you find a repeatable way to do this, let me know how you did it.
• If you run out of memory, Doodle will abort and then reset your Pilot. This can happen when you launch Doodle for the very first time if there isn't enough memory to allocate the initial database.
• Doodle can suffer from the Tap Bug, in which the Pilot invents a pen tap nowhere near the current stylus location. I've had this happen on a Pilot 1000 running PalmOS 1.0.6, so this isn't limited to the new PalmPilots.

Background

Writing Doodle was interesting because I discovered that a user interface can work much differently on a pen based computer. Since doodling consists of scribbling with the stylus on the screen of your Pilot, it's quite natural to change pens or inks by reaching into the graffiti area and scribbling a command character. It's almost as if you reached out with your stylus and dipped it into a one ink pot of an array, but the palette of inks is organized gesturally in the graffiti stroke "space" rather than arranged physically in your workspace. The result is that the mechanics of the user interface for Doodle do not contend with the mechanics of doodling - there are no rectilinear menus that must be traversed and there are no tool bars stealing eye-share from your doodle, it's just you, your stylus, and a field of empty pixels to be filled.

Scribble inspired Doodle both by providing the source code for a Pilot application to work from, and by providing an example of a paint program which was too minimalist to keep this doodler happy. Scribble occupies even less space, about 2000 bytes of code, on your Pilot.

Dinky Pad, the current premier paint package for the Pilot, occupies 10 time that space. It provides more drawing tools, a vertically scrollable image, text labels for your pictures, and a growing collection of DinkyComics and DinkyWomen image files to download.

Use the Source, ...

Doodle is a C program. built with Jeff Dionne's gcc based tools on a Linux system. Please help yourself to the sources for Doodle, just don't pass them off as your own or try to sell them or sue me because they don't do what you want.