You can use transform.scale() to scale a surface up or down to a certain size. You pass in the surface you want to scale, the size you want to scale it to, and an optional destination surface to set it to in case you don't want the function to return a new surface. The destination surface must be the same size as the final size for your scaled surface, however.
```Python
smallSurface = pygame.surface(20, 20)
bigSurface = pygame.transform.scale(smallSurface, (100, 100)) #scales smallSurface up to (100, 100) and stores it in bigSurface 
giantSurface = pygame.surface(200, 200)
pygame.transform.scale(bigSurface, (200, 200), giantSurface) #scales bigSurface up to (200, 200) and stores it in giantSurface
```

Scale a Surface in Pygame

You can use transform.flip() to flip a surface vertically, horizontally, or both. You pass in the surface you want to flip, a bool for flipping it horizontally, and a bool for flipping it vertically.
```Python
unflippedSurface = pygame.surface(20, 20)
flippedSurface = pygame.transform.flip(unflippedSurface, true, false) #flipped horizontally but not vertically
```

Flipping a Surface in Pygame

You can use transform.rotate() to rotate a surface counterclockwise by a certain number of degrees. You pass in the surface you want to rotate and a float representing the angle, which will rotate the image counterclockwise by that amount. If you pass in a negative angle, however, it will rotate the surface clockwise. The function will return the rotated surface as a new surface object.
```Python
unrotatedSurface = pygame.surface(20, 20)
rotatedSurface = pygame.transform.rotate(unrotatedSurface, 90) 
#rotate surface by 90 degrees clockwise
```

Rotating a Surface in Pygame

You can scale and roatate a surface using transform.rotozoom(). This will rotate a surface by a number of degrees, just like transform.rotate(), while also scaling the surface to a certain size, just like transform.scale().
```Python
rotozoom(Surface, angle, scale) -> Surface
normalSurface = pygame.surface(20, 20)
transformedSurface = rotozoom(normalSurface, 90, (100, 100)) 
#transform the original surface by rotating it 90 degrees and scaling it up to 100x100 pixels
```

Scaling and Rotating a Surface in Pygame

The different operations that can be performed with the transform module are:
- Scale
- Flip
- Rotate
- Rotozoom

University of Michigan - Ann Arbor

The transform module contains various transform operations. These are operations that alter a surface's scale and rotation in some way. Some transforms are destructive in the sense that they result in pixels being lost, which means there are specific techniques required to continuously scale a surface up without losing too many pixels.

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