QFract -- a Qt based fractal viewer

QFract is a fast viewer for Mandelbrot set, Julia set and so on.

Supported platforms are:
- Mac OS X (10.4 or later),
- Windows (with MinGW),
- Linux, Mac OS X+X11, FreeBSD, etc. on X Window System.

QFract is licensed under GNU GPL v2 (so far).
Since Qt open source edition is licensed under LGPL from version 4.5,
I might change the license to BSDL or something in the future...

Usage:

i) Launch and quit

Double click qfract.app for Mac and qfrct.exe for Windows to launch.
For Linux, move to the build directory and run:

$ ./qfract

To quit, select [File]->[Quit] ([qfract]->[Quit qfract]
for Mac) or close all windows.

ii) Basic instruction
When qfract has launched the Mandelbrot set is displayed in the window.

ii-1) Zooming
To zoom, drag the mouse with the right button to select the region to zoom.
The picture of the selected region will appear in a new window.

ii-2) Drawing forward orbit
If [Settings]->[Forward orbit] is select,
the forward orbit corresponding the position of the mouse pointer
is drawn. 

Note that forward orbits do not necessarily start at the mouse pointer
because in the parameter space, usually the forward orbit of a critical
point (or critical value) in the parameter pointed by the pointer is drawn,
while the forward orbit of the point is drawn in the phase space.

Select [Forward orbit] again to stop drawing.

ii-3) Creating child window
In pictures of parameter spaces, you can open child window
to draw phase spaces or another parameter spaces.
Select [Settings]->[Create child window].

By clicking the original picture, the picture with the corresponding
parameter is shown in the child window.

ii-4) Parameters
By selecting [Settings]->[Set parameters...],
you can change parameters, the size of the picture, the region,
and the maximal iteration times.

iii) Other functionalities

iii-1) Function plugins
QFract can display various kind of pictures drawn by iterative methods.
Selecting [Settings]->[Load function plugins...],
you can choose many functions.

Function plugins are dynamically loaded.
To load function plugins not in the dialog, or your own function plugins,
push [Open File...] button in the dialog.

Some function plugins use static variables in C language,
so opening several windows (especially with different parameters) might
cause a problem.

iii-2) Colormaps
Select [File]->[Load color map...] to change the colormap of the picture.
Recommended colormap is automatically chosen for each function plugin,
you do not usually need to use this functionality.

Changing colormap causes redrawing the picture, so if you need to change
colormap for a picture that needs a long time to draw, first try changing
colormap with very low iterate.

iii-3) Save
You can save pictures in PNG format by selecting [File]->[Save...].

iii-4) Load
You can load pictures saved by qfract by selecting [File]->[Open...].
Only PNG file saved by qfract is supported. 
(Do not try other PNG files because I did not code error handling...)

iii-5) Print
You can print pictures by selecting [File]->[Print...].
