python - Calculating the fraction of each cell in a grid overlapped by a 2D object -

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i have arbitrary rectangular cartesian grid divided potentially 10^6 or rectangular cells. (arbitrary means $x$ grid along points $x_1,...x_n$ , same goes $y$ grid.) draw arbitrary object on top of (say rotated rectangle, or circle), , efficiently calculate fraction of each cell overlapped object: if cell entirely inside bounds of object, 1.0; if cell entirely outside, 0.0; if half of cell covered object, 0.5. if displayed image , scaled 1 black , 0 white, result antialiased drawing of black object.

my application question in python, , seems capability might provided existing graphics library. there python module test fractional intersection of rectangle , arbitrary object? there python library can @ least efficiently test if point inside arbitrary object rotated rectangle?

you use pycairo, has fast native routines drawing. it's antialiased default.

implementing drawing algorithms in python slow.


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