Module Osg.State

module State: sig .. end

Encapsulates the current applied OpenGL modes, attributes and vertex arrays settings, implements lazy state updating and provides accessors for querrying the current state.

The venerable Red Book says that "OpenGL is a state machine", and this class represents the OpenGL state in OSG. Furthermore, State also has other important features:

It works as a stack of states (see State.push_state_set and State.pop_state_set). Manipulating this stack of OpenGL states manually is seldom needed, since OSG does this in the most common situations.
It implements lazy state updating. This means that, if one requests a state change and that particular state is already in the requested state, no OpenGL call will be made. This ensures that the OpenGL pipeline is not stalled by unncessary state changes.
It allows to query the current OpenGL state without calls to glGet*(), which typically stall the graphics pipeline (see, for instance, State.capture_current_state and State.get_model_view_matrix).

type t

osg::State holder.