public async Task <string> DownloadModelToLocalStorageAsync()
{
var worked = false;
var mainFilePath = string.Empty;
#if ENABLE_WINMD_SUPPORT
// Grab the list of Uris/Files that make up the remote model. Note that there
// is an assumption that the first file here will be the actual GLB/GLTF file
// otherwise the code below which sets mainFilePath will not work.
var remoteUrisForModel = await DownloadRemoteUriListForModelAsync();
if (remoteUrisForModel.Count > 0)
{
worked = true;
// Add into that the URI for the anchor file so that we download this too
var remoteAnchorFileUri = FileStorageManager.GetAnchorFileRelativeUri(
this.modelIdentifier);
remoteUrisForModel.Add(remoteAnchorFileUri);
// Iterate through and download each one of those files if we need to.
for (int i = 0; ((i < remoteUrisForModel.Count) && worked); i++)
{
// Recurse down & make sure we have a file in the right folder to store
// this locally.
var localFile = await FileStorageManager.GetStorageFileForRelativeUriAsync(
remoteUrisForModel[i]);
// Store off the first local file path as we assume that will be the .GLB or
// GLTF file.
if (i == 0)
{
mainFilePath = localFile.Path;
}
// We want the size of that file.
var properties = await localFile.GetBasicPropertiesAsync();
// If the file was already there with > 0 size then we will not overwrite it.
// (as a cheap form of caching)
if (properties.Size == 0)
{
// Go grab the file from the remote HoloLens web server and store
// the bits locally.
worked = await DownloadToStorageFileAsync(remoteUrisForModel[i], localFile);
}
}
}
#endif // ENABLE_WINMD_SUPPORT
return(worked ? mainFilePath : string.Empty);
}
async Task <List <string> > DownloadRemoteUriListForModelAsync()
{
// We first download the file list which tells us which files make up the model.
var fileListUri = FileStorageManager.GetFileListRelativeUri(this.modelIdentifier);
// Get a local storage file within the 3D objects folder to store that into.
var fileListLocalFile = await FileStorageManager.GetStorageFileForRelativeUriAsync(
fileListUri);
// Download the remote file list.
await DownloadToStorageFileAsync(fileListUri, fileListLocalFile);
// Read the bill of materials - the files that make up the model.
var remoteFileUris = await FileIO.ReadLinesAsync(fileListLocalFile);
return(remoteFileUris.ToList());
}
