Ubuntu Manpage: icetStrategy -- set the strategy used to composite images.

Provided by: paraview_4.0.1-1ubuntu1_amd64

NAME

       icetStrategy -- set the strategy used to composite images.

Synopsis

       #include <IceT.h>

       void icetStrategy(   IceTEnum   strategy  );

Description

The IceT API comes packaged with several algorithms for compositing images. The algorithm
to use is determined by selecting a strategy. The strategy is selected with icetStrategy.
A strategy must be selected before icetDrawFrame is called.

A strategy is chosen from one of the following provided enumerated values:

ICET_STRATEGY_SEQUENTIAL
Basically applies a ``traditional'' single tile composition (such as binary swap)
to each tile in the order they were defined. Because each process must take part in
the composition of each tile regardless of whether they draw into it, this strategy
is usually inefficient when compositing for more than one tile, but is recommended
for the single tile case because it bypasses some of the communication necessary
for the other multi-tile strategies.

ICET_STRATEGY_DIRECT
As each process renders an image for a tile, that image is sent directly to the
process that will display that tile. This usually results in a few processes
receiving and processing the majority of the data, and is therefore usually an
inefficient strategy.

ICET_STRATEGY_SPLIT
Like ICET_STRATEGY_DIRECT, except that the tiles are split up, and each process is
assigned a piece of a tile in such a way that each process receives and handles
about the same amount of data. This strategy is often very efficient, but due to
the large amount of messages passed, it has not proven to be very scalable or
robust.

ICET_STRATEGY_REDUCE
A two phase algorithm. In the first phase, tile images are redistributed such that
each process has one image for one tile. In the second phase, a ``traditional''
single tile composition is performed for each tile. Since each process contains an
image for only one tile, all these compositions may happen simultaneously. This is
a well rounded strategy that seems to perform well in a wide variety of multi-tile
applications. (However, in the special case where only one tile is defined, the
sequential strategy is probably better.)

ICET_STRATEGY_VTREE
An extension to the binary tree algorithm for image composition. Sets up a
``virtual'' composition tree for each tile image. Processes that belong to multiple
trees (because they render to more than one tile) are allowed to float between
trees. This strategy is not quite as well load balanced as ICET_STRATEGY_REDUCE or
ICET_STRATEGY_SPLIT, but has very well behaved network communication.

Not all of the strategies support ordered image composition. ICET_STRATEGY_SEQUENTIAL,
ICET_STRATEGY_DIRECT, and ICET_STRATEGY_REDUCE do support ordered image composition.
ICET_STRATEGY_SPLIT and ICET_STRATEGY_VTREE do not support ordered image composition and
will ignore ICET_ORDERED_COMPOSITE if it is enabled.

Some of the strategies, namely ICET_STRATEGY_SEQUENTIAL and ICET_STRATEGY_REDUCE, use a
sub-strategy that composites the image for a single tile. This single image strategy can
also be specified with icetSingleImageStrategy.

Errors

       ICET_INVALID_ENUM
               The strategy argument does not represent a valid strategy.

Warnings

       None.

Bugs

       None known.

Copyright

       Copyright (C)2003 Sandia Corporation

       Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government
       retains certain rights in this software.

       This source code is released under the New BSD License.