replaceVertices(at:_:)
Replaces the entire contents of a vertex buffer synchronously on the CPU.
Declaration
final func replaceVertices<R, E>(at index: Int, _ body: @_lifetime(0: copy 0) (inout MutableRawSpan) throws(E) -> R) throws(E) -> R where E : Error, R : ~CopyableParameters
- index:
The vertex buffer index to replace.
- body:
A closure that receives a mutable span over the buffer’s bytes and fully populates it.
Discussion
You pass a closure that receives a mutable span representing the contents of the vertex buffer. Upon entry the buffer’s contents are undefined; the closure is responsible for populating it with valid data. This span is valid only for the duration of the closure.