Wondering if this is a bug or expected behavior?
Using a vector to mask a bitmap works great. But if I try to use a bitmap to mask another bitmap, it just uses the bounding box and ignores the alpha.
https://ibb.co/WtGCqRG
Bitmap masking?
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- synthsin75
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Re: Bitmap masking?
If the image is a PNG, it will mask within the visible area of the image.
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Re: Bitmap masking?
Try disabling GPU Acceleration...

Masking previews in the workspace can be inaccurate when GPU Acceleration is enabled, and using a bitmap layer as a mask is one of the situations where it can fail. For example, in the above image, the red square is a vector layer but the white 'gingerbread man' cutout used as the mask is a bitmap layer painted in Photoshop.
This one of the reasons why I keep GPU Acceleration disabled most of the time, and I only enable it when I need it.
Either way, this limitation is a display issue and it doesn't affect the final render quality. Press ctrl-R to check.
Hope this helps.

Masking previews in the workspace can be inaccurate when GPU Acceleration is enabled, and using a bitmap layer as a mask is one of the situations where it can fail. For example, in the above image, the red square is a vector layer but the white 'gingerbread man' cutout used as the mask is a bitmap layer painted in Photoshop.
This one of the reasons why I keep GPU Acceleration disabled most of the time, and I only enable it when I need it.
Either way, this limitation is a display issue and it doesn't affect the final render quality. Press ctrl-R to check.
Hope this helps.
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Re: Bitmap masking?
Thanks Greenlaw! It works like a charm 

Re: Bitmap masking?
Cool! Glad that helped!
There are situations when GPU Acceleration is clearly helpful, like when there are lots of high-res bitmaps or very complex vector layers in the project, or when I need to see certain effects more accurately in the display port.
But most of the time I find it's better to leave GPU Acceleration switched off.
There are situations when GPU Acceleration is clearly helpful, like when there are lots of high-res bitmaps or very complex vector layers in the project, or when I need to see certain effects more accurately in the display port.
But most of the time I find it's better to leave GPU Acceleration switched off.
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