FracTest supports numerous options on the command line. These can be used to start it in batch mode, or to set up cluster computing; they can also be used to automate fractal rendering. These options are described here.

Command Line Overview

FracTest has three distinct modes of operation, which are selected on the command line:

Each of these has its own set of applicable command-line parameters, which will be described in the following sections.

To see the full set of available options, use the command

java -jar FracTest.jar --help

This will list the usage for all three modes.

Interactive Mode

In interactive mode, the following options are available:

usage: FracTest [ -OJX ] [ --no-local ] [ --stats ] [ --overwrite ] [ --jpeg ] [ --exit ] [ --report ] [ -s session-name ] [ --threadfac multiplier ] [ --threads nthreads ] [ --servers server-names ] [ -r dpi ] [ -p precision ] [ -S size-name ] [ -P prog-name ] [ -A aa-name ] [ png-file ] -s session-name Work in the named session. --threadfac multiplier Threads = number of CPUs * multiplier. --threads nthreads Force number of threads to use. --no-local Don't use the local host as a compute server. --servers server-names Use the named, comma-separated compute servers. --stats Output performance stats while rendering. -r, --resolution dpi Set the display resolution in DPI. -p precision Use the named numeric precision. -S size-name Use the named image size. -P prog-name Use the named progressive rendering mode. -A aa-name Use the named AA mode. -O, --overwrite Save the result over the original file. -J, --jpeg Save the result to a JPEG file. -X, --exit Exit on completion. --report Print a performance report after rendering.

-s session-name, --session session-name

Run in the named session. If it can't be opened, for example if it is in use, the session chooser will appear to allow you to choose a different session.

--threadfac multiplier

Normally, each machine used for computation will have a number of work threads created on it equal to the number of logical CPUs it has: i.e. CPUs × 1. You can override that with this parameter, which is the number which will be multiplied by the number of CPUs to get the number of threads. For example, if you only want half the usual number of threads, use --threadfac 0.5.

You can use values greater than 1 to increase the number of threads. This threading factor will be sent to all servers.

--threads nthreads

This option forces each machine to use the specified number of threads.

--no-local

This prevents an internal compute server being created on the current host. To do any work, you will need to add other servers.

--servers server-names

The argument server-names is a comma-separated list of compute servers to use for computation. The cluster computing page has more information on this.

--stats

Tells FracTest to periodically (every minute, currently) output some stats while computing. Not much maintained, and not much use at the moment.

--resolution dpi

Set the display resolution in DPI. Unfortunately Java doesn't do a very good job of determining the display resolution; if the layout doesn't work well, this parameter might help.

-p precision

Use the named numeric precision for computation. One of:

Normally, leave this on "auto".

-S size-name

Render to the named image size, which is one of:

This is useful when providing a png-file on the command line; it overrides the image size in that file's parameters.

-P prog-name

Sets the progressive rendering mode to the named mode, which is one of:

This is useful when providing a png-file on the command line; it overrides the progressive mode in that file's parameters.

-A aa-name

Sets the anti-aliasing mode to the named mode, which is one of:

This is useful when providing a png-file on the command line; it overrides the AA mode in that file's parameters.

--overwrite

When rendering a named png-file, save the result over the original file.

--jpeg

When rendering a named png-file, save the result to a JPEG file.

--exit

When rendering a named png-file, exit on completion.

--report

When rendering a named png-file, print a performance report after rendering.

png-file

Load and render the named PNG file. The parameters above can be used to override the image size, AA mode, etc.

This can be useful for automating certain tasks. For example, a performance benchmark can be obtained with a command like this:

java -jar FracTest.jar -p fx-8 -S qhd \ -P six_pass -A off --report -X Test.png >> log.txt

Batch Mode

In batch mode, the following options are available:

usage: FracTest --batch [ --no-local ] [ --stats ] [ -s session-name ] [ --threadfac multiplier ] [ --threads nthreads ] [ --servers server-names ] [ -r dpi ] [ --watch watch-folder ] [ --output-folder folder ] [ -S size-name ] [ -P prog-name ] [ -A aa-name ] -s session-name Work in the named session. --threadfac multiplier Threads = number of CPUs * multiplier. --threads nthreads Force number of threads to use. --no-local Don't use the local host as a compute server. --servers server-names Use the named, comma-separated compute servers. --stats Output performance stats while rendering. -r, --resolution dpi Set the display resolution in DPI. --watch watch-folder In batch mode, watch the given folder for jobs. --output-folder folder In batch mode, place rendered files here. -S size-name Use the named image size. -P prog-name Use the named progressive rendering mode. -A aa-name Use the named AA mode.

The parameter --batch signals that Fractest is to run in batch mode. Many of the remaining parameters are described above. The unique ones are described here:

-s session-name, --session session-name

Run in the named session. Unlike interactive mode, if the named session can't be opened, FracTest will fail with an error message. The default session for batch mode is Batch.

--watch watch-folder

Watch the given folder for jobs. Described fully on the batch mode page.

--output-folder folder

In batch mode, place rendered files here. The default is "Output".

Server Mode

In server mode, the following options are available:

usage: FracTest --server [ --port num ] --port num Run the server on the given port.

The parameter --server signals that Fractest is to run in server mode. There is one other option:

--port num

Runs the server on the given port number. On the controller, you will need to add this port number to the server's host name, as in server:1234.

This is useful to run multiple servers on one machine.