CSC111 Lab 10 2018

D. Thiebaut (talk) 11:30, 8 April 2018 (EDT)

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Solution Program

# lab10sol.py
# D. Thiebaut
# A collection of functions for manipulating an image
# using nested for loops.  Each function corresponds to a 
# transformation that was introduced in the lab.

from graphics import *

# We measured the image dimensions to be 243x207
# We make the window the same size
WIDTH  = 243
HEIGHT = 207


def sideways( img ):
    global WIDTH, HEIGHT
    for x in range( WIDTH ):
       for y in range(  x  ):
           # make sure y does not get larger than height of image
           if y < HEIGHT:
                # modify color of pixel at x, y...
                red, green, blue = img.getPixel( x, y )
                grey  = int( 0.3 * red +0.6 * green +0.11 * blue )
                color = color_rgb( grey, grey, grey )
                img.setPixel( x, y, color )
                
def blackAndWhite( img, win ):
    """sets the red component of the pixels of the image
    to their maximal value"""
    global WIDTH, HEIGHT
    for x in range( WIDTH ):
        win.update()
        for y in range( HEIGHT ):
            red, green, blue = img.getPixel( x, y )
            grey  = int( 0.3 * red +0.6 * green +0.11 * blue )
            color = color_rgb( grey, grey, grey )
            img.setPixel( x, y, color )


def saturate( component ):
    """transforms component into min or max value depending
    on its intensity."""
    if component < 125:
       return 0
    return 255


def AndyWarhol( img ):
    """saturates the image by saturating the 
    RGB components.  If the R component is less than 125, then
    set it to 0, otherwise set it to 255.   Same for blue and green."""

    global WIDTH, HEIGHT
    for x in range( WIDTH ):
        for y in range( HEIGHT ):
            red, green, blue = img.getPixel( x, y )
      
            # the line below replaces the pixel with its original color.  Change
            # the amount of red, green and blue to see some change in the colors
            newColor = color_rgb( saturate(red), saturate(green), saturate(blue) )
            img.setPixel( x, y, newColor )

def makeRed( img ):
    """sets the red component of the pixels of the image
    to their maximal value"""
    global WIDTH, HEIGHT
    for x in range( WIDTH ):
        for y in range( HEIGHT ):
            red, green, blue = img.getPixel( x, y )
            img.setPixel( x, y, color_rgb(255, green, blue ) )

def pixelate( img, win ):
    global WIDTH, HEIGHT
    img.undraw(  )
    for x in range( 0, WIDTH, 10 ):
        for y in range( 0, HEIGHT, 10 ):
            red, green, blue = img.getPixel( x, y )
            circ = Circle( Point( x, y ), 5 )
            circ.setFill( color_rgb( red, green, blue ) )
            circ.draw( win )
                      
def addBorder( img ):
    """add a red border around the image"""
    global WIDTH, HEIGHT
    for x in range( WIDTH ):
        for y in range( 6 ):
            img.setPixel( x, y, color_rgb(255, 0, 0 ) )
        for y in range( HEIGHT-5, HEIGHT ):
            img.setPixel( x, y, color_rgb(255, 0, 0 ) )

    for y in range( HEIGHT ):
        for x in range( 6 ):
            img.setPixel( x, y, color_rgb(255, 0, 0 ) )
        for x in range( WIDTH-5, WIDTH ):
            img.setPixel( x, y, color_rgb(255, 0, 0 ) )

def addRedDiagonal( img ):
    """draws a red diagonal going from the top-left corner
    of the image down."""
    global WIDTH, HEIGHT
    for x in range( 0, WIDTH ):
        y = x
        if y < HEIGHT:
            red, green, blue = img.getPixel( x, y )
            img.setPixel( x, y, color_rgb( 255, 0, 0 ) )

def addRedCross( img ):
    """draws a red cross going from the top-left corner
    of the image down, and from top-right corner down to
    lower left side of the image."""
    global WIDTH, HEIGHT
    for x in range( 0, WIDTH ):
        y = x
        if y < HEIGHT:
            red, green, blue = img.getPixel( x, y )
            img.setPixel( x, y, color_rgb( 255, 0, 0 ) )

    for x in range( WIDTH-1, -1, -1 ):
        y = WIDTH-1-x
        if y < HEIGHT:
            red, green, blue = img.getPixel( x, y )
            img.setPixel( x, y, color_rgb( 255, 0, 0 ) )
    
def symmetry( img ):
    """draws the image horizontally symmetrical around the
    vertical middle of the image"""
    global WIDTH, HEIGHT
    for x in range( 0, WIDTH//2 ):
        x2 = WIDTH-1-x
        for y in range( 0, HEIGHT ):
            red, green, blue = img.getPixel( x, y )
            img.setPixel( x2, y, color_rgb(red, green, blue ) )

def fog( img ):
    """creates a fog effect, making the pixels more and more
    white as we get closer to the bottom of the window."""
    global WIDTH, HEIGHT
    for x in range( 0, WIDTH ):
        for y in range( 0, HEIGHT ):
            red, green, blue = img.getPixel( x, y )
            percent = 1.0 * y / HEIGHT
            red   = int( red + (255-red)*percent )
            green = int( green + (255-green)*percent )
            blue  = int( blue + (255-blue)*percent )
            img.setPixel( x, y, color_rgb(red, green, blue ) )
    
def waitForClick( win, message ):
    """ waitForClick: stops the GUI and displays a message.  
    Returns when the user clicks the window. The message is erased."""

    # wait for user to click mouse to start
    startMsg = Text( Point( win.getWidth()/2, win.getHeight()-15 ), message )
    startMsg.draw( win )    # display message
    win.getMouse()          # wait
    startMsg.undraw()       # erase



def main():
    # open the graphic window
    win = GraphWin( "Your name here", WIDTH, HEIGHT )

    # create an image with its center corresponding to the center
    # of the window.  
    img = Image( Point(WIDTH//2, HEIGHT//2), "catHat.gif", )

    # make the image appear in the window
    img.draw( win )

    # transform the pixels of the image
    #makeRed( img )

    # create Andy Warhl image
    #AndyWarhol( img )

    # make the image black and white
    #blackAndWhite( img, win )

    # apply a sideways transformation
    #sideways( img )

    # add a border
    #addBorder( img )

    # add a red diagonal to the image
    #addRedDiagonal( img )

    # add a red cross to the image
    #addRedCross( img )

    
    # pixelate the image
    pixelate( img, win )

    # symmetrical cat in fog
    #symmetry( img )
    #fog( img )
    
    # close the window when the user clicks on it
    waitForClick( win, "click to close" )
    win.close()

main()

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