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+Context
+=======
+
+The context object represents the purest, most directly accessible, abilities
+of the device's 3D rendering pipeline.
+
+Methods
+-------
+
+CSO State
+^^^^^^^^^
+
+All CSO state is created, bound, and destroyed, with triplets of methods that
+all follow a specific naming scheme. For example, ``create_blend_state``,
+``bind_blend_state``, and ``destroy_blend_state``.
+
+CSO objects handled by the context object:
+
+* :ref:`Blend`: ``*_blend_state``
+* :ref:`Sampler`: These are special; they can be bound to either vertex or
+ fragment samplers, and they are bound in groups.
+ ``bind_fragment_sampler_states``, ``bind_vertex_sampler_states``
+* :ref:`Rasterizer`: ``*_rasterizer_state``
+* :ref:`Depth, Stencil, & Alpha`: ``*_depth_stencil_alpha_state``
+* :ref:`Shader`: These have two sets of methods. ``*_fs_state`` is for
+ fragment shaders, and ``*_vs_state`` is for vertex shaders.
+
+
+Resource Binding State
+^^^^^^^^^^^^^^^^^^^^^^
+
+This state describes how resources in various flavours (textures,
+buffers, surfaces) are bound to the driver.
+
+
+* ``set_constant_buffer``
+* ``set_framebuffer_state``
+* ``set_fragment_sampler_textures``
+* ``set_vertex_sampler_textures``
+* ``set_vertex_buffers``
+
+
+Non-CSO State
+^^^^^^^^^^^^^
+
+These pieces of state are too small, variable, and/or trivial to have CSO
+objects. They all follow simple, one-method binding calls, e.g.
+``set_edgeflags``.
+
+* ``set_edgeflags``
+* ``set_blend_color``
+* ``set_clip_state``
+* ``set_polygon_stipple``
+* ``set_scissor_state``
+* ``set_viewport_state``
+* ``set_vertex_elements``
+
+
+Clearing
+^^^^^^^^
+
+``clear`` initializes some or all of the surfaces currently bound to
+the framebuffer to particular RGBA, depth, or stencil values.
+
+Clear is one of the most difficult concepts to nail down to a single
+interface and it seems likely that we will want to add additional
+clear paths, for instance clearing surfaces not bound to the
+framebuffer, or read-modify-write clears such as depth-only or
+stencil-only clears of packed depth-stencil buffers.
+
+
+Drawing
+^^^^^^^
+
+``draw_arrays``
+
+``draw_elements``
+
+``draw_range_elements``
+
+
+Queries
+^^^^^^^
+
+Queries gather some statistic from the 3D pipeline over one or more
+draws. Queries may be nested, though no state tracker currently
+exercises this.
+
+Queries can be created with ``create_query`` and deleted with
+``destroy_query``. To enable a query, use ``begin_query``, and when finished,
+use ``end_query`` to stop the query. Finally, ``get_query_result`` is used
+to retrieve the results.
+
+Flushing
+^^^^^^^^
+
+``flush``
+
+
+Resource Busy Queries
+^^^^^^^^^^^^^^^^^^^^^
+
+``is_texture_referenced``
+
+``is_buffer_referenced``
+
+
+
+Blitting
+^^^^^^^^
+
+These methods emulate classic blitter controls. They are not guaranteed to be
+available; if they are set to NULL, then they are not present.
+
+These methods operate directly on ``pipe_surface`` objects, and stand
+apart from any 3D state in the context. Blitting functionality may be
+moved to a separate abstraction at some point in the future.
+
+``surface_fill`` performs a fill operation on a section of a surface.
+
+``surface_copy`` blits a region of a surface to a region of another surface,
+provided that both surfaces are the same format. The source and destination
+may be the same surface, and overlapping blits are permitted.
+
+The interfaces to these calls are likely to change to make it easier
+for a driver to batch multiple blits with the same source and
+destination.
+