reveal.js

# Graphics

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CS 65 // 2021-02-16

## Extra Credit Activities
- [Lunch & Learn: Diversity in Service](https://www.eventbrite.com/e/lunch-learn-diversity-in-service-tickets-140108780133)
    + Thursday, 2/18 from noon to 1:00pm
- 
 [Career Conference](https://calendar.drake.edu/event/be_unstoppable_flexible_fearless_career_conference?utm_source=newsletter&utm_medium=email&utm_content=DETAILS&utm_campaign=Faculty-Feb-9#.YCLmlHdKhTY)
    + Friday, 2/19 from 9:00am to 4:00pm
- 
 [Songs for A New World](https://calendar.drake.edu/event/songs_for_a_new_world?utm_campaign=widget&utm_medium=widget&utm_source=Drake+University+Calendar) Livestream Performance
    + Thursday, 2/25 from 8:00 to 10:00am
- 
 [Global Citizen Forum](https://www.drake.edu/diversity/initiatives/globalcitizenforum2021/)
    + Conference on equity and inclusion in higher ed
    + March 3-5

# Assignment 3
- Due Thursday before class

# Questions
## .. about anything?

# "Objects" in Python

## Object-Oriented Programming
- Python is an **object-oriented language** and all basic values are implemented as "objects"
- 
 An **object** consists of the following:
    + 
 A collection of related **information**
    + 
 A set of **methods** (i.e. operations) to manipulate that information
- 
 For example, consider the string: `s = "abc"`
    + 
 Its basic information includes three characters

## Object-Oriented Programming
- Python also lets you create your own types of objects---called **classes**
- 
 When writing a class, you tell Python what **information** each object has and also what **methods** can be performed on it
- 
 We'll cover creating our own classes during week 11

# Graphics Library

## The graphics.py Library
- We are going to learn the **Zelle graphics library** that can be used to easily create simple, cross-platform, programs that include graphics
    + It is written using a larger library called **Tkinter**
- 
 The library comes with many **classes** that help facilitate various graphics tasks
- 
 When using the graphics library, you must have access to the **graphics.py** file that is provided on the **Resources** page of the course website

## The graphics.py Library
- To import the graphics classes, use:
    + `from graphics import *`
- 
 Once the library is loaded, a **GraphWin** object can be created to display a graphical window to the user
    + 
 You can also **draw** shapes and interact with the window via **mouse movements** and **click events**
- 
 You can create a GraphWin object calling its **constructor**
    + 
 `win = GraphWin()`
- 
 You can also create various **graphics objects**

# DEMO

# Graphics Classes

## Summary of Classes
- **GraphWin**
    + A "window" that acts like a canvas and can be shown to the user.
    + Has a width / height, background color, and ways to get input from the user

## Summary of Classes
- **GraphicsObject**
    + Any object that can be drawn to a GraphWin canvas has all the GraphicsObject methods
    + They have a position, fill color, etc.
    + The list of all GraphicsObject types are below:
    + Point, Line, Circle, Rectangle, Oval, Polygon, Text, Entry, and Image

# Lab Time