CS 1102 Individual Project
Implementing an Animation Language

Phase 1 (design) due Monday, September 29 (11:59pm)
Phase 2 (implementation) due Sunday, October 12 (11:59pm)

Project Description

You must design and implement a language for animating graphics on a canvas. Graphics can move or jump around the canvas, optionally stopping when a graphic bumps into something (like an edge of the canvas or another graphic). Graphics can also be added or removed during an animation. Here are three examples of animations.

sample animations

For this project, you will develop:

  1. A language for specifying animations such as these and

  2. A program (interpreter) that will run an animation written in your language, displaying it on the screen.

You will do the project in two stages: a language design stage, followed by an implementation stage. Each stage has a separate due date.

Project Goal

The goal of the project is to make sure each student can define, design, and implement a domain-specific programming language. This is an individual project -- you may not work with your homework partner, or any other students, on this project (see the collaboration policy for more details).

The Design Phase: DUE Monday, September 29, 11:59pm

For this phase, propose data definitions for a language for animations. At a minimum, your animation language must meet the following requirements:

Submit both the proposed language and examples showing how to represent all three sample animations, plus an animation of your own choosing, in your language.

You do not need to be able to run animation programs at the end of this stage. A nice syntax (ie, macros) for the language are not needed at this stage either (you can add those in the implementation phase). All you need to submit are the data definitions and examples of data that you need to capture animation programs, as you did for homework 4. Do not submit any function definitions for this phase.

What to Turn in

Submit an electronic file design.ss (under turnin name project-design) containing your work for this phase.

The Implementation Phase: DUE Sunday, October 12, 11:59pm

For this phase, you must provide a function run-animation that takes an animation in your language and runs it (displays the animation on the screen). Your animation should happen in one window over time---you are not trying to produce a sequence of still frames as shown in the samples.

You may decide to change or enhance your original language design as you write your interpreter. That's fine (even expected -- implementing helps you assess your design decisions). Your project report will describe all changes you decided to make.

We will use a customized version of the world teachpack (called world-manual.ss) for the graphics. The original world teachpack, which you used for the fire-plane assignment, iteratively generated successive frames for you. The modified teachpack removes this feature, so that you have to generate successive frames yourself, in accordance with the commands in your language. This requires three key functions from the new teachpack:

If you choose to add a macro front-end to your language, you will need to work in the "Pretty Big" language level, which doesn't support teachpacks. In this case, the following line at the top of your file will load the teachpack into your implementation:

(require "world-manual.ss")
This assumes you've saved the teachpack file to the same directory as your project file.

The Project Report

Provide a text file with answers to the following questions:

  1. What must the TA do to run your program? Provide concrete instructions (such as "execute (run-animation animation1)"), including a list of the animations you defined as your test cases. The staff won't grade a program that they can't run.

  2. What is the status of your implementation? Explain which features/aspects work and which don't. If you didn't get the repeating commands to work, for example, say so. This gives the staff guidelines on how to test your system.

  3. How have you changed your design since the version you submitted for the design deadline? Explain the changes and why you made them (i.e., I found I couldn't do X because of problem Y with my earlier definition). We're interested in seeing what doing the implementation taught you about the language design.

  4. What, if anything, do you think could be cleaner in your design or implementation? If you are satisfied with your design, say so. If you think certain aspects should really be easier to use, easier to write, etc, explain those aspects and what you'd like to see different. No danger of losing points for honesty here (you'll only lose points for problems that we can detect without reading your report) -- we just want to hear your assessment as we determine our own.

What to Turn in

  1. A file animations.ss containing your work for this phase.

  2. A file report.txt containing your project report. Please submit these in plain text, rather than in Word or PDF format.

Submit these via turnin, under the name project-final.


In general, the design phase counts for 25% of your project grade, the implementation phase (including final language design) for 70%, and your project report for 5%.

Design Phase Grading

We will grade your language designs on a 4-grade scale (check+, check, check-, no credit). At this stage, we're looking to see whether you thought out the design phase well -- did you identify appropriate data and commands? Does your design adequately support the given examples? Does your work demonstrate that you know what data definitions for languages look like?

There's no single right answer for this part, and while we will make suggestions on your designs, we won't give you a single right answer to follow when doing your implementation. Part of the exercise is for you to have to work with, and perhaps revise, your initial language design when it comes time to implement your animation system. Grades in this phase are more about how well you cover the sample animations than your low-level design decisions (which we fully expect to change as you start to implement the project).

Implementation Phase Grading

In the implementation phase, we will be looking at your final language design and its implementation. More specifically:

Some General Notes on Grading

Collaboration Policy

This is an individual project. Collaboration is not permitted on this assignment (not even with your homework partner). The course staff are the only people you may approach for help with this project (but do come to us if you need help). You may not ask anyone outside of the course staff questions on any aspect of this project. This includes:

Violations of this policy follow the general course collaboration policy, and will likely result in an NR for the course.

Why this policy? Given the fairly open collaboration policy on homeworks, this assignment helps us assess how much each student understands of the course material. Since some students struggle in timed situations such as exams, the project gives you a more open-ended setting in which to demonstrate what you've understood of the course material.