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Meta-tool is a special (from the usage point of view) kind of a drawing tool that does not do anything on its own, but modifies behavior of another tool.
For example the brush tool can be modified to select pixels instead of drawing using the selection tool or to brighten the affected pixels using the retouch tool, etc.
Meta-tools are usually using the underscore character (_) to separate its name from the name of the internal tool. Identifier of the selection with brush tool would be: SELECT_BRUSH.
Theoretically, it is possible to use multiple meta-tools, but only seldom would that combination make any sense. It is also possible to use the same meta-tool multiple times. STYLIZE_BUBBLE_STYLIZE_TEXT is one of the few useful combinations, but these meta-tools are currently only available in RealWorld Photos.
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Find out how Vista icons differ from XP icons.
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