liebgott Posted November 12, 2008 Report Share Posted November 12, 2008 Can someone explain to me the use of a mask. What purpose does it serve?Barbara Quote Link to comment Share on other sites More sharing options...
Lin Evans Posted November 12, 2008 Report Share Posted November 12, 2008 Hi Barbara,There are various types of "masks" which are useful. First, a "mask" in one sense is some image which sets in front of another image on a different layer and limits the extent of one's view of the image on the underneath layer. An example of this would be perhaps a PNG file which had a "rectangular" transparency area cut in the center allowing that part the image on the layer beneath the mask to show through in that cut-out area of the mask. One could zoom the image on the lower layer and the "mask" would prevent that portion of the zoomed image residing behind the mask from showing.Think of the CRT screen itself as a "mask". When a small rectangular image is zoomed it gets larger on all four borders until finally the extent of the CRT's viewing area prevents one from seeing the "edges" growing as the zoom increases. By using a black rectangular PNG "mask" the viewing area of the CRT can be diminished just as if you were to cut out a rectangular space in a black piece of paper and place it over the CRT so that the only portion of the image you would see would be what was visible through the cut-out. Think of the mask as simply an electronic piece of black paper.The second type of "layer mask" is one which lets you see the image or portion of image on an underlying layer without having to have a black PNG "cut-out" and while still seeing that part of the image on the upper layer which is not masked.In this scenario, the "mask" itself, unlike a black PNG mask is "invisible" but the "hole" or transparent part of the mask which can be any shape or size lets the underlying image be seen through that transparent part. It's possible with PTE to have "multiple" masks which allow multiple parts of multiple images to be seen simultaneously showing through the main image. In this scenario, any portion of the mask itself which is "black" will allow the main image to be seen while any portion of the mask which is "white" will allow the image on the layer beneath to show through the main image.Best regards,LinCan someone explain to me the use of a mask. What purpose does it serve?Barbara Quote Link to comment Share on other sites More sharing options...
liebgott Posted November 13, 2008 Author Report Share Posted November 13, 2008 Lin--thank you. But what puzzles me is why would anyone want a mask--I can understand a png but not the reason to use a mask. I guess I sound stupid but I love to understand and I do make "shows" for family and friends which are relatively sophisticated as a result of following you and the forum. Quote Link to comment Share on other sites More sharing options...
Lin Evans Posted November 13, 2008 Report Share Posted November 13, 2008 Hi Barbara,See my answer to you on your other post for how and why....Best regards,Lin Quote Link to comment Share on other sites More sharing options...
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