Summary

A simple IDE, in which one can learn to program in a useful language (Python). It will be backed up with some simple libraries for drawing shapes to a savable canvas, making sounds, etc. It will have examples, and good documentation.

The target audience are children and teenagers with an interest in computers, but no previous programming knowledge.

Rationale

Back in the days of microcomputers with BASIC interpreters it was very easy to start to learn to program. You just did: 

10 PRINT "hello world"
RUN

From there, there was little barrier to learning, all the way up to using things like sound and graphics. These days there are a couple of barriers. People aren't used to typing into a command line (a good thing). GUI's are hard to program. The choice of languages is more complex.

A project to help young people learn to program is very important for the future of free software.

Use cases

Scope

An IDE and some supporting libraries that make it simple and interesting to learn some basic programming concepts using Python:

Python will be used so that the user can easily move on to more general programming. Student programs will be runnable on the fly as well as "exported" or built into binaries.

The IDE will be supplemented with fun, easy to use classes for graphics, sound, and text interaction with the user.

To make this application useful, a significant part of the effort will be the creation of documentation, example projects, and templates. The example projects and templates will demonstrate what can be done with the language and offer a starting point for student work. The documentation will consist of a quick reference for checking syntax, as well as a full set of lessons to walk students through their first "Hello World" all the way to a more advanced application.

The IDE will "grow" along with the student, allowing them to eventually switch to "advanced" mode where they can see imported modules, and use all of python's features.

Design

IDE

Graphical User Interface Requirements

Code Editing and Project Requirements

Functional Requirements

Libraries

Graphics The graphics library will allow the programmer to create a drawing window, fill it in with various colors, draw shapes and text, and possibly create some simple animations by making good use of a rendering loop. The library will support the express creation of basic shapes, as well as custom shapes following Cairo's "place the pen down and move it around" methodology. It will also be possible to load images and place them in the window. Most paramaters will have default values. For example, draw.placeImage() will need at minimum its first parameter, the rest will be initialized to the top-left corner, 1:1 scaling, and no rotation.

The interface for the currently-nameless (codenamed "draw") library is as follows: 

draw.new(width, height) # Create a new drawing window, destroying any others
draw.background(color) # Set the drawing window's background color
draw.clear() # Clears the drawing surface

#Primitive shapes
draw.drawRectangle(x, y, width, height, fillColor, borderColor, borderWidth)
draw.drawCircle(x,y, radius, fillColor, borderColor, borderWidth)

#Custom shapes
draw.penDown(startX, startY, penColor)
draw.penMove(newX, newY)  # Move to the next point
draw.penUp(fillColor)     # Optionally fills in the region

#Placing Images
draw.placeImage(resourceImage, x, y, scaleX, scaleY, rotateDegrees)

#Text
draw.write(msg, x, y, font, fontSize, fontColor)

The library is intentionally simple to encourage our future programmers to learn the utility of custom functions, and to create their own such as drawDecahedron().

Sound We are interested in playing some nice open formats as well as the arbitrary single-frequency tone beep. 

# I wrote part of "Mary Had a Little Lamb" once
# It took me hours.
sound.beep(pitch,length)

#Playing sound files
sound.startSound(resourceSound, loop=false)
sound.stop()
sound.pause()
sound.resume()

Utility Library We want to give our programmers some control over the flow of the program, as well as allowthem to easily get input from the user in our environment. This library brings all of these together into a single package. 

#Controlling program flow
program.wait(seconds)
program.end()

#Controlling the terminal
program.clearScreen()
program.setTextColor(color)
program.setBackgroundColor(color)

# User interaction
program.inputNumber(min, max)
program.inputString(maxLen)
program.waitAnyKey()

Documentation and Help

At the center of this learning tool is the documentation and help system. The "Help Bar" can be activated at any time during normal editing, and includes the following items:

Help Bar Sections

When the full help system is launched in a new window, the user can browse through the sections of the help:

A. Tutorial

  1. Introduction to SPA
  2. Your first program
  3. Conditional logic
  4. Using loops
  5. Drawing Graphics
  6. Creating sounds
  7. Custom functions
  8. Classes
  9. Moving On

B. How Do I? C. Quick Lookup

  1. for
  2. if
  3. ...

The full documentation is split into three levels. The first is the Tutorial, which will contain full explanations for the aspiring programmer. It will be full of practical examples and information. The next level down is the "How Do I" section, which contains quick guides for those who don't want to trudge through the whole Tutorial, or those who need a refresher. The third and final level is the quick lookup, for long-time users who know exactly what they're looking for.

Implementation

The IDE is being programmed in Python, using GTK for the user interface. The sound library wraps the functionality of gstreamer, and the graphics library wraps Cairo. The utility library will be composed of a variety of custom functions from scratch and from the Python API. The diagram creator could be Dia or graphviz.

The final product should realize and adhere to the requirements and interfaces layed out in the "Design" section of this page. The project should not be considered complete unless all of the requirements are satisfied and fully functional.

Data preservation and migration

Outstanding issues

BoF agenda and discussion

Comments

CategorySpec

simple-prog-app (last edited 2008-08-06 17:00:38 by localhost)