VTK Developers authored Apr 09, 2012 and Brad King committed Apr 09, 2012

Move source files from their former monolithic VTK location to their new
location in modular VTK without modification.  This preserves enough
information for "git blame -M" and "git log --follow" to connect
modularized VTK files to their original location and history.

Co-Author: Marcus D. Hanwell <marcus.hanwell@kitware.com>
Co-Author: Chris Harris <chris.harris@kitware.com>
Co-Author: Brad King <brad.king@kitware.com>
Co-Author: Nikhil Shetty <nikhil.shetty@kitware.com>

Change-Id: Id69a252ddab397cbef204de76ebda9b462d59bd6

The old value 255 was not large enough when the chart is displayed with a
1024 pixel width. It was make the texture pixelated.

By default vtkScalarsToColorsItem uses the bounds defined by the transfer
function range. The user might want to use different bounds.

-You can edit control points in 2 fashions:
 If vtkControlPointsItem::StrokeMode is true, you can "draw" points while
the left mouse button is down, it will add control points under the mouse
cursor.
 If vtkControlPointsItem::StrokeMode is false, you can drag&drop existing
points. SwitchPointsMode control the behavior to follow when a point
crosses another.
In both modes, if you click the left button mouse not on a point, a point is
created under the mouse cursor.
-Add vtkCompositeControlPointsItem to mix ct function and opacity function.
It creates points for Color Transfer and Opacity
functions.Both functions will share the same control points.
-Add vtkControlPointsItem::EditPoint to control midpoint and sharpness
-Support null transfer functions in the ScalarsToColors items

-You can edit control points in 2 fashions:
 If vtkControlPointsItem::StrokeMode is true, you can "draw" points while
the left mouse button is down, it will add control points under the mouse
cursor.
 If vtkControlPointsItem::StrokeMode is false, you can drag&drop existing
points. SwitchPointsMode control the behavior to follow when a point
crosses another.
In both modes, if you click the left button mouse not on a point, a point is
created under the mouse cursor.
-Add vtkCompositeControlPointsItem to mix ct function and opacity function.
It creates points for Color Transfer and Opacity
functions.Both functions will share the same control points.
-Add vtkControlPointsItem::EditPoint to control midpoint and sharpness
-Support null transfer functions in the ScalarsToColors items

and vtkCompositeTransferFunctionItem), specially if the option
MaskAboveCurve is off.

They can be added into any vtkChartXY. Their size depend on the
vtkScalarsToColors (vtkLookupTable or vtkColorTransferFunction) range.

vtkPiecewiseFunctionItem and vtkCompositeTransferFunctionItem can mask
pixels above the alpha value.