Corner tiles mirror the point evaluator's early returns: helper-box accept, then outer-corner reject/full-cover proof, then the inner-boundary proof f

Straight-edge tiles use the same early-return shape as the point evaluator: first prove the tile fully inside the outer edge, then prove it stays clea

@brief Assigns an alpha byte to a color that is already known to be opaque. @param c Source color. @param fraction_color Alpha value to assign, typica

Returns true for a blending mode when a transparent destination implies transparent result.

Returns true for a blending mode when a transparent source implies transparent result.

Scans a row of nibbles starting at (data, phase) for the first nibble that equals 'value'. Returns the offset (in nibbles from start) of the first mat

Fast containment check for the straight-edged portion of the inner boundary.

Returns the rounded-corner quadrant that owns this pixel. A `-1` result means the pixel lies on one of the straight slabs, so the corner-circle math c

Whole-tile version of `SelectRoundedCorner()`. A non-negative result proves the entire tile lives in one corner quadrant, which lets the classifier us

Signed distance to the straight slab of the round rect. Positive means the pixel center is inside the slab, negative means it lies outside it.

In practice, seems to be measurably faster than actually dividing by 255 and counting on the compiler to optimize.

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Symmetrical to applySingleSourceInPlace.