FreeMat: vtkPixelBufferObject

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vtkPixelBufferObject

Section: Visualization Toolkit Rendering Classes

# Usage

Provides low-level access to GPU memory. Used to pass raw data to GPU. The data is uploaded into a pixel buffer.

To create an instance of class vtkPixelBufferObject, simply invoke its constructor as follows

      obj = vtkPixelBufferObject

# Methods

The class vtkPixelBufferObject has several methods that can be used. They are listed below. Note that the documentation is translated automatically from the VTK sources, and may not be completely intelligible. When in doubt, consult the VTK website. In the methods listed below, `obj` is an instance of the vtkPixelBufferObject class.

- `string = obj.GetClassName ()`
- `int = obj.IsA (string name)`
- `vtkPixelBufferObject = obj.NewInstance ()`
- `vtkPixelBufferObject = obj.SafeDownCast (vtkObject o)`
- `obj.SetContext (vtkRenderWindow context)` - Get/Set the context. Context must be a vtkOpenGLRenderWindow. This does not increase the reference count of the context to avoid reference loops. SetContext() may raise an error is the OpenGL context does not support the required OpenGL extensions.
- `vtkRenderWindow = obj.GetContext ()` - Get/Set the context. Context must be a vtkOpenGLRenderWindow. This does not increase the reference count of the context to avoid reference loops. SetContext() may raise an error is the OpenGL context does not support the required OpenGL extensions.
- `int = obj.GetUsage ()` - Usage is a performance hint. Valid values are:
  - StreamDraw specified once by A, used few times S
  - StreamRead specified once by R, queried a few times by A
  - StreamCopy specified once by R, used a few times S
  - StaticDraw specified once by A, used many times S
  - StaticRead specificed once by R, queried many times by A
  - StaticCopy specified once by R, used many times S
  - DynamicDraw respecified repeatedly by A, used many times S
  - DynamicRead respecified repeatedly by R, queried many times by A
  - DynamicCopy respecified repeatedly by R, used many times S A: the application S: as the source for GL drawing and image specification commands. R: reading data from the GL Initial value is StaticDraw, as in OpenGL spec.
- `obj.SetUsage (int )` - Usage is a performance hint. Valid values are:
  - StreamDraw specified once by A, used few times S
  - StreamRead specified once by R, queried a few times by A
  - StreamCopy specified once by R, used a few times S
  - StaticDraw specified once by A, used many times S
  - StaticRead specificed once by R, queried many times by A
  - StaticCopy specified once by R, used many times S
  - DynamicDraw respecified repeatedly by A, used many times S
  - DynamicRead respecified repeatedly by R, queried many times by A
  - DynamicCopy respecified repeatedly by R, used many times S A: the application S: as the source for GL drawing and image specification commands. R: reading data from the GL Initial value is StaticDraw, as in OpenGL spec.
- `int = obj.GetType ()` - Get the type with which the data is loaded into the GPU. eg. VTK_FLOAT for float32, VTK_CHAR for byte, VTK_UNSIGNED_CHAR for unsigned byte etc.
- `int = obj.GetSize ()` - Get the size of the data loaded into the GPU. Size is in the number of elements of the uploaded Type.
- `int = obj.GetHandle ()` - Get the openGL buffer handle.
- `obj.BindToPackedBuffer ()`
- `obj.BindToUnPackedBuffer ()` - Inactivate the buffer.
- `obj.UnBind ()` - Inactivate the buffer.