Island¶

class pyslm.hatching.Island(origin=array([[0., 0.]]), orientation=0.0, islandWidth=0.0, islandOverlap=0.0, hatchDistance=0.1)¶

Bases: pyslm.hatching.hatching.InnerHatchRegion

Island represents a square sub-region containing a series of orthogonal hatches which represents a typically a checkerboard scan strategy.

Attributes Summary

`hatchDistance`	The distance between adjacent hatch vectors
`islandOverlap`	The length of overlap between adjacent islands in both directions \((x', y')\)
`islandWidth`	The square island width

Methods Summary

`boundary`()	Returns the transformed boundary obtained from `localBoundary()` into the global coordinate system \((x,y)\).
`generateInternalHatch`([isOdd])	Generates a set of hatches orthogonal to the island’s coordinate system \((x', y')\).
`hatch`()	Generates a set of hatches orthogonal to the island’s coordinate system depending on if the sum of `posId` is even or odd.
`localBoundary`()	Returns the local square boundary based on the island width (`islandWidth`) and the island overlap (`islandOverlap`).

Attributes Documentation

hatchDistance¶

The distance between adjacent hatch vectors

Return type:: float

islandOverlap¶

The length of overlap between adjacent islands in both directions \((x', y')\)

Return type:: float

islandWidth¶

The square island width

Return type:: float

Methods Documentation

boundary()¶

Returns the transformed boundary obtained from localBoundary() into the global coordinate system \((x,y)\).

Return type:: Polygon
Returns:: Boundary polygon

generateInternalHatch(isOdd=True)¶

Generates a set of hatches orthogonal to the island’s coordinate system \((x', y')\).

Parameters:: isOdd (bool) – The chosen orientation of the hatching
Return type:: ndarray
Returns:: (nx3) Set of sorted hatch coordinates

hatch()¶

Generates a set of hatches orthogonal to the island’s coordinate system depending on if the sum of posId is even or odd. The returned hatch vectors are transformed and sorted depending on the direction.

Return type:: ndarray
Returns:: The transformed and ordered hatch vectors

localBoundary()¶

Returns the local square boundary based on the island width (islandWidth) and the island overlap (islandOverlap). The island overlap provides an offset from the original boundary, so the user must compensate the actual overlap by a factor of a half. The boundary is cached into a static class attribute :attr:Island._boundary` since this remains constant typically across the entire hatching process. If the user desires to change this the user should re-implement the class and this method.

Return type:: ndarray
Returns:: Coordinates representing the local boundary