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UnionRegionOfs

Computes the Boolean union of two regions and offsets the result.

Declaration

ibool NAPI GA_regionFuncs::UnionRegionOfs(
    GA_region *r1,
    const GA_region *r2,
    N_int32 dx,
    N_int32 dy)

Prototype In

snap/graphics.h

Parameters

r1

Region with which r2 is unioned, and also becomes the result region.

r2

Region to be unioned with r1

dx

Offset to add to all x coordinates in region 2

dy

Offset to add to all y coordinates in region 2

 

Return Value

True if the union is valid, false if an empty region was created.

Description

Computes the Boolean union of two regions for the area covered by region r1 and region r2, computing the resulting region in r1, which may result in an empty region. This routine also adds the specified (x,y) offset value to all the coordinates in region 2 before they are unioned with region 1, which allows you to quickly do a union with a translated region without needing to explicitly translate the region itself. If you need to retain the value of r1, you need to first copy r1 to a temporary region.

See Also

DiffRegion, SectRegion, UnionRegion, UnionRegionRect

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