Gradient across stroke, inside opacity mask is thresholded for half the width of the stroke
Applying a black-to-white gradient across a stroke inside an opacity mask results in a portion of the opacity mask not being applied, corresponding to half the width of the stroke, almost as if it is clipped by the stroke. If the path is subsequently outlined, which creates a mesh, the behavior is the same. If the object is a filled bezier curve, the behavior is normal with the shape masked as expected.
Chris Clark
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Chris Clark
commented
Example image. The behavior is even stranger if you shift the position of the white stop in the gradient slider. The black stop behaves correctly. In CMYK, the white stop thresholds the masking to a different position! I think that is the key to understanding the bug. Still perfect in RGB.
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Chris Clark
commented
Illustrator 30.3. Behavior is the same in CPU or GPU. I have an Apple M3 Max (integrated GPU).
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Chris Clark
commented
Hi Egor, it seems to occur only in CMYK documents, not RGB documents, even if RGB colors for black and white are explicitly selected in the opacity mask.
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Interesting. I use strokes across path in opacity mask in every third project (I mean it), but I never had a clipping like this.
Chris, can you please share this test file? I try to make it happen and it works OK.
Are you on 30.3? Same in Beta? Same in both RGB and CMYK docs? Same on CPU Preview? (what is your GPU?)
