PhotoPlus X2 User Guide - Serif

46 Manipulating Images
Check Antialias to smooth the colour selection edge; uncheck the
option for a more jagged edge.
Check Contiguous to include only pixels connected to the clicked pixel;
uncheck to include similar pixels throughout the layer.
The Context toolbar also includes a Use All Layers option. If checked,
pixels are sampled on all layers (both shown and hidden) under the click
point, as if the layers were merged into one. If unchecked, it only samples
pixels on the active layer.
For any selection tool, the Context toolbar includes combination buttons (New,
Add, Subtract, and Intersect) that determine the effect of each new selection
operation. For example, starting with a square selection (created with the New
button), here's what a second partly overlaid square (shown with a solid blue line)
might produce with each setting:
New
Add
Subtract
Intersect
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