Example Usage

Already used by Kamaelia.Visualisation.PhysicsGraph.TopologyViewer.

Rendering a grid in light grey with grid cell size of 100x100:

grid = GridRenderer(size=100, colour=(200,200,200))
renderer = grid.render( <pygame surface> )
for rendering_pass in renderer:
  print "Rendering for pass ", rendering_pass

How does it work?

Instances of this class provide a render() generator that renders horizontal and vertical grid lines to conver the specified pygame surface. The colour and spacing of the grid lines are specified at initialisation.

Rendering is performed by the generator, returned when the render() method is called. Its behaviour is that needed for the framework for multi-pass rendering that is used by TopologyViewer.

The generator yields the number of the rendering pass it wishes to be next on next. Each time it is subsequently called, it performs the rendering required for that pass. It then yields the number of the next required pass or completes if there is no more rendering required.

A setOffset() method is also implemented to allow the rendering position to be offset. This therefore makes it possible to scroll the grid around the display surface.

See TopologyViewer for more details.