CSC 220 - Fall 2020 - Assignment 1, due by 11:59 PM on 9/24/2020 via D2L.

Handout sketch CSC220F20AvatarClassInAvatarRoom with my working solution as a starting point.
Here is the Assignment 1 specification.
See the spring 2018 csc120 course page for instructions on how to zip and submit a sketch containing multiple files.
Unified Modeling Language (UML) class diagram of my working solution.
Understand the following diagram & concepts for the fall 2019 midterm exam, updated 10/6/2019. Study this for MIDTERM 10/17/2019.

1. 

    A Java interface specifies operations that must be implemented in subclasses.
        Interface inheritance is inheritance of an interface's specifications.
            Interfaces enable plugging various derived class (subclass) objects into a framework such as a Processing sketch.
            Interface Avatar allows different Avatar derived-class objects to perform display, movement, & collision detection.
        Implementation inheritance, in contrast, inherits the implemented data fields & methods of a class down into a derived class.
    An abstract class such as AvatarHelper supplies some data fields & helper methods. It is incomplete.
    A concrete class such as Professor, Furniture, or Paddle is complete. A sketch can construct an object of this class.
    Polymorphism means that a class derived fron an interface or class can take many forms.
        Professor, Furniture, and Paddle are three forms of interface Avatar and abstract class AvatarHelper.
        A derived class like Paddle can redefine a base-class function like Furniture.display() by rewriting it completely,
                while using other data fields or functions of Furniture as-is.
        A derived class like Paddle can extend a base-class function like Furniture.display() by adding some new code in Paddle.display(),
                then calling super.display() to call the base class function.
    Reuse such as reusable library classes is another key object-oriented design principle.

Notes from 2018's project 1:

If you are scaling a body part such as making an eye get bigger and smaller, there are a few things you need to do:
1. Add a field like "float eyescale = 1.0;" inside your avatar class.
2. Add another field like "float eyespeed = .01;" for the speed at which the eye grows & shrinks.
3. Update that variable "eyescale" inside the move() function, e.g., by making it shrink and grow between 0.0 and 2.0, using a small increment per move() found in "eyespeed". Change sign of eyespeed similar to speedX when it hits its limits.
4. In the display() function:
    pushMatrix(); // additional push for the eye
    translate(...);    // to the location of the eye, relative to the 0,0 point of the avatar.
    scale(eyescale);
    PLOT THE EYE USING SHAPE FUNCTIONS LIKE ellipse(...);
    popMatrix();    // discard the scale, put 0,0 back to center of avatar

Without this nested push-pop, your scale would apply to every body part after the eye.