ENH: Remove old checkerboarding code.

Rendering/vtkImageSliceMapper.cxx

@@ -427,32 +427,3 @@ void vtkImageSliceMapper::GetDimensionIndices(
       }
     }
 }
-
-//----------------------------------------------------------------------------
-void vtkImageSliceMapper::CheckerboardImage(
-  unsigned char *data, int xsize, int ysize,
-  const double imageSpacing[3], vtkImageProperty *property)
-{
-  // Get the imagedata dims that correspond to the texture "x" and "y"
-  int xdim, ydim;
-  this->GetDimensionIndices(this->Orientation, xdim, ydim);
-
-  // Get the checkerboard spacing and the offset fraction
-  double spacing[2], offset[2];
-  property->GetCheckerboardSpacing(spacing);
-  property->GetCheckerboardOffset(offset);
-
-  // Adjust the spacing according to the image data spacing, add a tolerance
-  // to prefer rounding up since ties happen often and can cause different
-  // platforms/compilers to give different results
-  spacing[0] = floor(spacing[0]/imageSpacing[xdim] + 0.50000762939453125);
-  spacing[1] = floor(spacing[1]/imageSpacing[ydim] + 0.50000762939453125);
-
-  // Center the checkerboard at the image center, because it looks nice
-  offset[0] = floor(0.5*xsize + spacing[0]*offset[0] + 0.50000762939453125);
-  offset[1] = floor(0.5*ysize + spacing[1]*offset[1] + 0.50000762939453125);
-
-  // Note that spacing has been converted to integer spacing
-  vtkImageMapper3D::CheckerboardRGBA(
-    data, xsize, ysize, offset[0], offset[1], spacing[0], spacing[1]);
-}

Rendering/vtkImageSliceMapper.h

@@ -154,12 +154,6 @@ protected:
   // Get the dimension indices according to the orientation.
   static void GetDimensionIndices(int orientation, int &xdim, int &ydim);
 
-  // Description:
-  // Do a checkerboard pattern to the alpha of an RGBA image
-  void CheckerboardImage(
-    unsigned char *data, int xsize, int ysize,
-    const double imageSpacing[3], vtkImageProperty *property);
-
   vtkTimeStamp LoadTime;
   int SliceNumber;
   int SliceNumberMinValue;

Rendering/vtkOpenGLImageSliceMapper.cxx

@@ -232,28 +232,19 @@ void vtkOpenGLImageSliceMapper::RenderTexturedPolygon(
       renWin->GetContextCreationTime() > loadTime ||
       recursive)
     {
-    // whether to try to use the input data directly as the texture
-    bool reuseData = true;
-    if (checkerboard && !useFragmentProgram && !this->ExactPixelMatch)
-      {
-      reuseData = false;
-      }
-
     // get the data to load as a texture
     int xsize = this->TextureSize[0];
     int ysize = this->TextureSize[1];
     int bytesPerPixel = this->TextureBytesPerPixel;
 
+    // whether to try to use the input data directly as the texture
+    bool reuseData = true;
+
+    // generate the data to be used as a texture
     unsigned char *data = this->MakeTextureData(
       (this->PassColorData ? 0 : property), input, extent, xsize, ysize,
       bytesPerPixel, reuseTexture, reuseData);
 
-    // software fallback for checkerboarding the image
-    if (checkerboard && !useFragmentProgram && !this->ExactPixelMatch)
-      {
-      this->CheckerboardImage(data, xsize, ysize, spacing, property);
-      }
-
     GLuint tempIndex = 0;
 
 #ifdef GL_VERSION_1_1