minor.
attempt to XCopyArea on smallest area possible.
optimize cell drawing.
fix indentation.
Revert "optimize cell drawing."

This reverts commit 29ae5ea48c85d8c41f226edec818e38d0071a0a9.
Revert "attempt to XCopyArea on smallest area possible."

This reverts commit 024d8d4c3d3ac0017287122b889f9230c6147e86.