Fix black grid line artifacts on nearest-neighbor interpolation

[ktgw0316]

No description provided.

[jodygarnett]

@aaime while this is not covered by a test, it does agree with the implementation of jai-ext AffineNearestOpImage.java.

The change was made in JAI-Ext codebase here: geosolutions-it/jai-ext@2ff26ee

Bilinear interpolation optimization on the affine operation and minor fixes

[jodygarnett]

This implementation agrees with jai-ext codebase implementation:

                    javax.media.jai.util.Range clipRange = performScanlineClipping(
                            src_rect_x1,
                            src_rect_y1,
                            // Last point in the source is
                            // x2 = x1 + width - 1
                            // y2 = y1 + height - 1
                            src_rect_x2 , src_rect_y2 , s_ix, s_iy, ifracx, ifracy,
                            dst_min_x, dst_max_x, 0, 0, 0, 0);

I note that for both implementation the comment may not be correct after the change proposed here.

[jodygarnett]

@aaime does my review above seem on track? General approach is to compare against JAI-Ext codebase and see if the same problem has been already "fixed" in production.

[jodygarnett]

Revisit this change after JAI-Ext merged, it seemed to already be addressed.

[jodygarnett]

JAI-Ext merged, please reopen if this problem still remains in 0.9.1 release.