Many people don't use the Visibility Mask in Painter. To them it is just an extra complex step that gets in the way of painting.
The same can be said for a lot of Painter's extras. Like the mosaic for example or the curves palette. Some folks just want to paint, and Painter is mighty good at it too.
Eventually everyone gets around to exploring the other stuff. And if you ever get round to the Visibility Mask, you can be in for a nasty surprise. You see the principal seems simple enough, there is a Vis Mask (not to be confused with the User Mask) which controls what parts of a layer is visible. That's what it says in the book.
However if you try to erase pixels on an unfilled layer using the Vis Mask. It seems to do what it is supposed to. However if you try and make the pixels visible again you will get nasty black artifacts in your stroke and also around the edges of your stroke.
You might wonder what you are doing wrong. But fear not you are not doing anything wrong. As crazy as it may seem (especially if you are used to a layer mask such as the one in Photoshop) this is how it works in Painter. Some people have come up with "work arounds" like selecting before erasing but this is not very effective for a complex stroke although it does help a bit.
The sad fact is you are not going crazy, it's just another badly engineered part of Painter. If you don't use Vis Masks then it wont bother you. However if you are a Photoshop user and think that the Vis Mask is a layer mask you will have a tough time. Actually I don't know what the purpose of the Vis Mask actually is. It is just a half baked Layer Mask.
Below are some samples: the green stroke has been made invisisble with the Vis Mask then it has been restored but as you can see the problems are obvious.
In case you are wondering Corel have decided not to do anything about this at all it P7, in fact they have indicated to me that it is only a possibility that they will even think about it for P8.
This post is just to reassure the unwary that it is not you who is doing something wrong. In the meantime you'll have to do your layer masking in Photoshop.
thelonious
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