test equality for pygame.font.Font-CodePudding

I was trying to make a font cache like this:

from ._utils import SizedDict
def copysurf(x,mod):
    if mod:
        return cs(x)
    return ImmutableSurface(x)
class FontCache:
    def __init__(self):
        self.cache = SizedDict(20)
        self.fmisses = 0
        self.fhits = 0
        self.cmisses = {}
        self.chits = {}
    def getfor(self,font,char,aa,color):
        if font not in self.cache:
            self.cmisses[font] = 0
            self.chits[font] = 0
            self.cache[font] = SizedDict(300)
        if char not in self.cache[font]:
            self.cache[font][char] = font.render(char,aa,color)
        return self.cache[font][char].copy()
fontCache = FontCache()

(Sized dicts are also made by me,they are dicts that deletes the oldest entry if it exeeds the capacity specified in the constructor.)

But the problem arises when i tried to cache the font.You see,

pygame.font.SysFont("Courier",22) == pygame.font.SysFont("Courier",22)

is false,and the hash() function returned different values.As i know,there aren't any methods that returns the original NAME of the font,and we can't test equality by merely knowing the size and the bold and italic flags.

Any thoughts?

CodePudding user response：

You could subclass pygame.font.Font, store the metadata when the font is created. Something like this:

import pygame

pygame.init()


class Font(pygame.font.Font):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.properties = (args, tuple(kwargs.items()))

    def __hash__(self):
        return hash(self.properties)

    def __eq__(self, other):
        return self.properties == other.properties

    @classmethod
    def construct(cls, fontpath, size, bold, italic):
        font = cls(fontpath, size)
        font.strong = bold
        font.oblique = italic
        return font


# Prints True
print(
    pygame.font.SysFont("Courier", 22, constructor=Font.construct)
    == pygame.font.SysFont("Courier", 22, constructor=Font.construct)
)