CS21: Graphics Quick Reference

To use the graphics library, first import it at the top of your program:

from graphics import *

Next create a new graphics window object, and then create gui objects to draw into this window:

   
# creates new GraphWin object, 500x500 pixels in size
win = GraphWin("My GUI Program", 500, 500)

# creates a new Circle object centered at 50,50 with a radius of 20 pixels
circ = Circle(Point(50,50), 20)

# invoke the setFill method of the Circle object refered to by circ 
circ.setFill("red")

# draw the circ object to the GraphWin win
circ.draw(win)

Here is some information about the GraphWin object and some of the Graphics objects you can use (section 5.8 of the text contains a complete reference for the classes in the graphics library):

class GraphWin

GraphWin(title, width, height) #Constructor-makes a new GraphWin object

close()
flush()  # update drawing to graphics window

getHeight()
getWidth()

# wait for mouse click and return Point obj representing click location
getMouse() 

setBackground(color)

setMouseHandler(func)  # func will be executed on mouse click

class Point


Point(x, y) #Constructor

clone()    # create a new Point object that is an exact copy of this one
getX()
getY()

Methods common to all Graphics Object classes:


draw(graphwin):    # Draw the object in graphwin, which should be a 
                   # GraphWin object.  A GraphicsObject may only be drawn 
                   # into one window. 
move(dx, dy):      # move object dx units in x and dy units in y direction
setFill(color):    # Set interior color to color
setOutline(color): # Set outline color to color
setWidth(width):   # Set line weight to width
undraw():          # Undraw the object (i.e. hide it).

class Line

Line(p1, p2)

clone()
setArrow(option)   
getCenter()
getP1()
getP2()

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)

class Rectangle


Rectangle( p1, p2)  # p1 and p2 are points for upper left lower rt

clone()
getCenter()
getP1()
getP2()

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)
undraw()

class Circle

Circle(p1, radius)       # p1 is a Point at the center of the circle

clone()
getCenter()
getRadius()
getP1()	  # returns a clone of the corresponding corner of the
getP2()	  # circle's bounding box (opposite corners of bounding square)

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)
undraw()

class Oval

Oval(p1, p2)       # p1 and p2 are opposite corners of bounding rectangle 

clone()
getCenter()
getP1()
getP2()

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)

class Polygon


Polygon(<list of points>)
# ex. triangle: Polygon ([Point(10,20), Point(30,40), Point(10,60)])

getPoints()  # return a list of Points in the polygon
clone()

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)
undraw()

class Text

Text(p, text)  # p is center point and text is string
    
clone()
getText()
setText(text)
setTextColor(color)
setFace(family)     # set font face, ex. "arial" "courier"
setSize(size)       # set font size (5-36 are legal)    
setStyle(style)     # set font style  ex.  "bold" "italic"

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)
undraw()

class Entry

GUI object into which user can type text

Entry(pt, width)     # pt is anchor Point (center)

getAnchor()          # returns the center Point
getText()            # returns the current text
setText(string)      # sets the text to string
setSize(point)       # sets the found size (5-36 are legal)
setStyle(style)      # sets the font style
setTextColor(color)  # sets the text color

draw(graphwin)
move(dx, dy)
setFill(color)
setOutline(color)
setWidth(width)
undraw()

Animation

For animation, you may need to import the sleep function from the time module.

from time import sleep
sleep(0.5) #pause for 0.5 seconds

CS21 Graphics