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[VPE Professional Edition and above]

Sets the current type for exported PDF documents. If the document is exported to PDF and Fast Web View is activated, the document is written as web-optimized PDF file. Adobe calls this 'Linearized PDF', an enhanced PDF file format especially for the Internet. It allows to view any given page on a client site as fast as possible without downloading the whole document from a server.

This feature is especially useful, if documents are created on a server and are transmitted to clients via a network. The client will be able to view the first page of the transmitted document - and to browse to specific pages in the document - as fast as possible, while the transmission is still in process.

Whilst non-optimized PDF documents are created by VPE in one single pass, where every page is written to the PDF file immediately, web-optimized documents are created internally in two passes: VPE can not write any part of the document, before it has analysed the complete document structure, because it needs to arrange the objects in the PDF document in a very special way according to the Adobe PDF specifications. In addition, some special tables (called "Hint Tables"), which contain information about the document structure, have to be created.

The disadvantage of the optimized mode is, that VPE needs more processor time and memory to perform the optimization. During the first pass, VPE keeps all objects of the document in memory and analyses the document structure. In a second pass VPE writes the document to the file. Depending on the number of simultaneous users and the overall workload of the server, this is no problem, if small documents with a few pages are created.

In case you require to create huge documents simultaneously for many users, you can instruct VPE to use a special swapping technique, so instead of using RAM memory, VPE will swap the information for all the objects in the document to a temporary file. This is done with a special technique and works very fast. (see VpeSetUseTempFiles() for details)

We recommend that you monitor the workload of the server. Depending on available free ram during a typical workload scenario, you should decide whether to use the swapping technology or not. Some tests also revealed that - depending on the scenario and contents of the document - the use of temporary files is significantly faster than using memory based document creation!
So our second recommendation is to measure the performance during a typical workload scenario with - and without - swapping, to decide what mode of operation to use.

Each temporary swap file is deleted automatically after a PDF document has been created.

void VpeSetFastWebView(

VpeHandle hDoc,

int yes_no

)

VpeHandle hDoc

Document Handle

int yes_no

Default:

False