I'm attempting to draw a basic "armorial achievement" (aka a "coat of arms"). I have a shield outlined with a bold stroke and there is a diagonal white stripe that passes through the shield.
I used the shield outline to create a clipping mask that I want to use for the entire shield (by expanding the outline and using that as the mask, which very nearly works). I'm applying the clipping mask by grouping everything first and then adding the mask to the group overall...
I am seeing artifacts of the white diagonal (with red outline) appearing outside the shield outline. Zooming in does show that the clipping algorithm handles the shield outline differently to the white diagonal (in other words the red and white areas are more clearly visible at higher zoom factors).
I'm convinced that nothing has been nudged out of place (the fact that both ends of the white part are having he same problem supports this) and that the shield outline thickness has not changed since I made the mask.
Is this a real problem or is it just a graphical / floating point error in my graphics engine telling me lies? If it's a real problem what can I do about it?