9.34: Flipping the Squirrel Image

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Page ID: 14655

\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

    if sq['movex'] < 0: # squirrel is facing left
        sq['surface'] = pygame.transform.scale(L_SQUIR_IMG, (sq['width'], sq['height']))
    else: # squirrel is facing right
        sq['surface'] = pygame.transform.scale(R_SQUIR_IMG, (sq['width'], sq['height']))
    sq['bounce'] = 0
    sq['bouncerate'] = random.randint(10, 18)
    sq['bounceheight'] = random.randint(10, 50)
    return sq

The L_SQUIR_IMG and R_SQUIR_IMG constants contain Surface objects with left-facing and right-facing squirrel images on them. New Surface objects will be made using the pygame.transform.scale() function to match the squirrel’s width and height (stored in sq['width'] and sq['height'] respectively).

After that, the three bounce-related values are randomly generated (except for sq['bounce'] which is 0 because the squirrel always starts at the beginning of the bounce) and the dictionary is returned on line 8 [372].