import { BufferAttribute as ThreeBufferAttribute , BufferGeometry as ThreeBufferGeometry , InterleavedBufferAttribute as ThreeInterleavedBufferAttribute } from "three" ; import { BufferAttribute , BufferElementType , Geometry , GeometryType , InterleavedBufferAttribute } from "./DecodedTile" ; /**
 * Collection of helper methods to convert
 *  https * to [[Geometry]] that allows creation and transfering of THREE BufferGeometry in webworkers.
 * See also [[CustomDatasourceExample]].
  export namespace ThreeBufferUtils { export function getBufferElementType ( buffer ) { if ( buffer instanceof Int8Array ) { return "int8" ; } else if ( buffer instanceof Uint8Array ) { return "uint8" ; } else if ( buffer instanceof Int16Array ) { return "int16" ; } else if ( buffer instanceof Uint16Array ) { return "uint16" ; } else if ( buffer instanceof Int32Array ) { return "int32" ; } else if ( buffer instanceof Uint32Array ) { return "uint32" ; } else if ( buffer instanceof Float32Array ) { return "float" ; } throw new Error ( `Unsupported buffer type ${ name }` ) ; } export function fromThreeBufferAttribute ( bufferAttribute ) { const buffer = ( bufferAttribute . array as any ) as ArrayBufferView ; return { name : bufferAttribute . name , buffer : buffer . buffer , type : getBufferElementType ( buffer ) , itemCount : bufferAttribute . itemSize , normalized : bufferAttribute . normalized } ; } export function fromThreeInterleavedBufferAttribute ( bufferAttribute ) { throw new Error ( "Not implemented yet" ) ; } export function fromThreeBufferGeometry ( bufferGeometry , techniqueIndex ) { const vertexAttributes = [ ] ; const attributeNames = Object . getOwnPropertyNames ( bufferGeometry . attributes ) ; for ( const name of attributeNames ) { const attribute = bufferGeometry . attributes [ name ] ; const vertexAttribute = fromThreeBufferAttribute ( attribute as ThreeBufferAttribute ) ; vertexAttribute . name = name ; vertexAttributes . push ( vertexAttribute ) ; } const index = bufferGeometry . index !== null ? fromThreeBufferAttribute ( bufferGeometry . index ) : undefined ; let count = 0 ; if ( index !== undefined ) { count = bufferGeometry . index === null ? 0 : bufferGeometry . index . count ; } else { const posAttr = bufferGeometry . attributes . position as ThreeBufferAttribute ; if ( posAttr === undefined ) { throw new Error ( "Missing position attibute to deduce item count" ) ; } count = posAttr . count ; } return { type : GeometryType . Unspecified , vertexAttributes , index , groups : [ { start : 0 , count , technique : techniqueIndex } ] } ; } }