GNU Rocket
==========

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GNU Rocket is an intuitive new way of... bah, whatever. It's a sync-tracker,
a tool for synchronizing music and visuals in demoscene productions. It
consists of a GUI editor (using Qt), and an ANSI C library that can either
communicate with the editor over a network socket, or play back an exported
data-set.

Compile Editor
--------------
The GNU Rocket editor uses qmake as a build-system abstraction, which can
be used to output Makefiles, Visual Studio project files or can be built
directly from QtCreator. See the qmake documentation for details.

Compile Example
---------------
GNU Rocket contains an example client called example\_bass. This is a simple
OpenGL, SDL 1.2 and BASS audio library application, that demonstrates how to
use the GNU Rocket API.

Before compiling the example, you need to make sure you have recent [SDL](http://www.libsdl.org/)
and [BASS](http://www.un4seen.com/) libraries and includes.

The header files and libraries can be installed local to the project by
copying all .lib-files to the example\_bass/lib/, all .h files to
example\_bass/include/, and all .dll files to the example\_bass/.

Once the prerequisites are installed, the example can be compiled either by
opening examples.sln and selecting "Build" -> "Build Solution" from Visual
Studio 2008, or by doing "make example_bass/example_bass" on Unix-base
systems.

Using the editor
----------------
The GNU Rocket editor is laid out like a music-tracker; tracks (or columns)
and rows. Each track represents a separate "variable" in the demo, over the
entire time-domain of the demo. Each row represents a specific point in time,
and consists of a set of key frames. The key frames are interpolated over time
according to their interpolation modes.

Interpolation modes
-------------------
Each key frame has an interpolation mode associated with it, and that
interpolation mode is valid until the next key frame is reached. The different
interpolation modes are the following:

* Step   : This is the simplest mode, and always returns the key's value.
* Linear : This does a linear interpolation between the current and the next
           key's values.
* Smooth : This interpolates in a smooth fashion, the exact function is what
           is usually called "smoothstep". Do not confuse this mode with
           splines; this only interpolates smoothly between two different
           values, it does not try to calculate tangents or any such things.
* Ramp   : This is similar to "Linear", but additionally applies an
           exponentiation of the interpolation factor.

Keyboard shortcuts
-------------------
Some of the GNU Rocket editor's features are available through the menu and
some keyboard shortcut. Here's a list of the supported keyboard shortcuts:

| Shortcut                 | Action                       |
|:-------------------------|:-----------------------------|
| Up/Down/Left/Right       | Move cursor                  |
| PgUp/PgDn                | Move cursor 16 rows up/down  |
| Home/End                 | Move cursor to begining/end  |
| Ctrl+Left/Right          | Move track                   |
| Enter                    | Enter key frame value        |
| Del                      | Delete key frame             |
| i                        | Enumerate interpolation mode |
| k                        | Toggle bookmark              |
| Alt+PgUp/PgDn            | Go to prev/next bookmark     |
| Space                    | Pause/Resume demo            |
| Shift+Up/Down/Left/Right | Select                       |
| Ctrl+C                   | Copy                         |
| Ctrl+V                   | Paste                        |
| Ctrl+Z                   | Undo                         |
| Shift+Ctrl+Z             | Redo                         |
| Ctrl+B                   | Bias key frames              |
| Shift+Ctrl+Up/Down       | Quick-bias by +/- 0.1        |
| Ctrl+Up/Down             | Quick-bias by +/- 1          |
| Ctrl+PgUp/PgDn           | Quick-bias by +/- 10         |
| Shift+Ctrl+PgUp/PgDn     | Quick-bias by +/- 100        |

Bugs and feedback
------------------
Please report bugs or other feedback to the GNU Rocket mailing list:
gnu-rocket@googlegroups.com