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23 lines
1.2 KiB
Markdown
23 lines
1.2 KiB
Markdown
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# Support `Fill` for `ArrayHandleStride`
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Previously, if you called `Fill` on an `ArrayHandleStride`, you would get
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an exception that said the feature was not supported. It turns out that
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filling values is very useful in situations where, for example, you need to
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initialize an array when processing an unknown type (and thus dealing with
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extracted components).
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This implementation of `Fill` first attempts to call `Fill` on the
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contained array. This only works if the stride is set to 1. If this does
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not work, then the code leverages the precompiled `ArrayCopy`. It does this
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by first creating a new `ArrayHandleStride` containing the fill value and a
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modulo of 1 so that value is constantly repeated. It then reconstructs an
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`ArrayHandleStride` for itself with a modified size and offset to match the
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start and end indices.
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Referencing the `ArrayCopy` was tricky because it kept creating circular
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dependencies among `ArrayHandleStride`, `ArrayExtractComponent`, and
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`UnknownArrayHandle`. These dependencies were broken by having
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`ArrayHandleStride` directly use the internal `ArrayCopyUnknown` function
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and to use a forward declaration of `UnknownArrayHandle` rather than
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including its header.
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