PHGraph is a very simple cocoa framework to display scientific plots in the plane, for osX tiger and leopard (universal binary).
Why another framework ? Because the plotting frameworks
I've been able to find here or there did not fulfill my
expectations, including the ability to display quickly and
efficiently plots with a large number of points.
Although it is a very young and immature framework, I
decided to make it public so that users, developers could
try it, discuss its evolution and in the effect that, if
major changes would appear necessary, doing it at the first
stages of development would make it much easier and
The design is simple : the major class is the view,
PHGraphView which inherits from NSView, and whose instance
variables are mostly three MutableArrays. One is an array
of horizontal axis, a second for vertical axis, and a third
for objects to be drawn in the view.
Several axis can be added (but I guess no one will ever use
more than two in each direction), as well as some objects,
subclassed from PHGraphObjects to be drawn on the plane.
See the class tree to see some objects implemented so far.
Each object is associated with a couple of axis. Each
object is responsible for its own drawing, and the modular
conception of the framework makes it very easy to expand
with user defined objects for example.
The PHGraphView itself is responsible for dealing with the
mouse events, with a few predefined modes. The most
convenient in my opinion is the PHCompositeZoomAndDrag : a
left click (mouse not moving) is a zoom in (centered), a
alt+left click is a zoom out (cancelling a zoom in), and
dragging the mouse with the button pressed moves the plot.
The framework takes care of it, but you could do it
yourself with a delegate as well...
For all the modes : the right click or control+left click
shows a contextual menu with the possibility to copy the
graph to the pasteboard as TIFF, PDF or EPS image.
The data for the set of points or curves is just the given
of references to double arrays. This way, there is no
memory wasted, and the fastest access to data in the
framework, and the plotting itself is for the major part
realized with core graphics (Quartz 2d), with some cocoa
for displaying strings.
See here for screenshots and code
Here for the TODO list,
Here for the distribution files