Drawing shapes

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Revision as of 21:39, 21 February 2018 by Admin (talk | contribs) (Rectangle)
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Make sure you are starting with a working pygame project, this will require you to install pygame and copy the code from the page below to make a start:

Basic pygame template

Rectangle

You can declare some variables to use for your rectangle, they require the x coordinate, the y coordinate, the width and the height:

LEFT = 100
TOP = 100
LENGTH = 20
WIDTH = 20
RECTCOORD = [LEFT, TOP, LENGTH, WIDTH]
rect1 = pygame.Rect(RECTCOORD)

This is the same as writing:

rect1 = pygame.Rect([100,100,20,20])

Colour

Before we can draw your rectangle to the screen we will need to define a colour to use:

RED = 255
YELLOW = 230
BLUE = 200
COLOR = (RED, YELLOW, BLUE)

Again this is the same as writing just:

COLOR = (255, 230, 200)

Draw the Rectangle

We can now draw the rectangle to the screen:

pygame.draw.rect(SCREEN, COLOR, rect1, 0)

The 0 will cause the shape to be filled with colour, a value above 0 will draw the outline only and use the number for the line thickness. For example:

pygame.draw.rect(SCREEN, COLOR, rect1, 1)

Update the screen

Now you have drawn something new to the screen we need to update it. We can just update a single object:

pygame.display.update(rect1)

or we can update everything:

pygame.display.update()