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DrawContext.IsAvailable

Method
Description:
Checks whether the facilities of this class are available for use in the current scope.
Remarks:

This class can perform drawing operations and access the state of parameters related to drawing only in lock-step with rendering inside of Revit. As a consequence, the facilities of this class are not available for use outside of the scope determined by the callback RenderScene(View, DisplayStyle). Certain methods of other DirectContext3D objects, e.g., VertexBuffer::Map() are similarly restricted by the same scope.

Syntax
public static bool IsAvailable()