AVTK - OpenAV Productions
This is the repository for AVTK, an Audio / Visual ToolKit.
General Info
AVTK is based on PUGL and Cairo, two great libraries. It minimizes what dependencies it has by using these two frameworks. PUGL is a cross platform GL abstraction, while Cairo provides fast vector graphic rendering to GL surfaces.
Avtk::UI
Avtk::UI is the main UI class, where the widget logic resides. The UI class wraps a PUGL view, and manages redrawing and theming of widgets. The UI pointer is passed to all widgets, which gives it a lot of flexibility to control other elements.
In order to write a custom UI, derive a class CustomUI
from Avtk::UI
, and
create some widgets in its CustomUI()
constructor. Add the created widgets
using the add( Avtk::Widget* )
function, which is inheritited from
Avtk::UI
.
The Avtk::UI
class uses a smart-pointer to manager the Widget*
instances
passed in, so we do not need to worry about memory leaks when dealing with
widgets in this way.
Widgets
The widget is the main UI element in AVTK. Creating custom widgets is very
easy: just derive from the widget class, and override the draw()
function. In
order to have proper mouse interaction for drag
and click
modes, checkout
widget.hxx
, which details what ClickMode
, DragMode
, and Scroll
options
there are.
The Widget
superclass has void value(float)
and float value()
methods,
for setting and getting the most important value of the widget. As not all
widgets can be described with one value (think an ADSR or other complex
widgets), add custom float getParamX()
and void setParamX( float )
functions. These will need to be explicity controlled by the UI, but there's no
way around that.
Themes
Each Avtk::UI
instance has a Theme*
, which contains the
current color values for the Theme
. Note that line-widths and
corner-rounded-ness are also contained within the Theme class.
Creating a new Theme can be done by deriving from the Theme
class, and then
overriding the float setColor( cairo_t* cr, USE_CASE uc, float alpha);
function. This function sets USE_CASE
color as the active color for Cairo
context cr
when it is called. When the given USE_CASE
exists in the theme
the custom setColor()
function returns non-zero: this tells Avtk to not apply
the default color.
If the setColor()
function returns null, then the default compiled in AVTK
theme will be used.
Building
To build a static library from the AVTK source:
git clone https://github.com/openAVproductions/openAV-AVTK
cd openAV-AVTK
mkdir build
cd build
cmake ..
make
The current directory now has two binaries
- The
avtkDemo
application, just run to see an AVTK UI - The
avtkTests
widget tester, run with a command line argument to test the specific widget. Examples include./avtkTests
and pass an argument from the following list:dialog
dial
group
key
list
number
Using
To use AVTK in your own application, it is recommended to copy the source code into your tree. This allows you to link statically to AVTK, which avoids a lot of issues when embedding plugins UIs. OpenAV does not intend to support dynamic linking of AVTK, or maintaining a backwards-compatilble ABI.
After building AVTK, a libavtk.a
static archive of AVTK is in the build
directory. Statically link your application against this .a file, and
you're ready to run!
License
AVTK is licensed under the 3-clause BSD license. This allows commercial use of the library.
Contact
If your using AVTK, my curiosity would like an email - this is however in no way mandatory.
Harry van Haaren harryhaaren@gmail.com OpenAV Productions openavproductions.com