Previously the render process consisted of looping through all rows and columns in the view-port. Any hidden rows or columns inside the view-port would have their height calculated and skipped if height was zero. Big sheets with lots of hidden rows were slow to render i.e #108.
This update skips these by storing visible row and column indices in the view-port. The renderer then only considers those in the render loop.
[x] Fix some issues with cell layout provider with visible row calculations
[x] Don't consider hidden rows or columns in the render loop
[x] Better handle the sheet when there are no visible rows or columns - virtualisation can break in these cases.
Previously the render process consisted of looping through all rows and columns in the view-port. Any hidden rows or columns inside the view-port would have their height calculated and skipped if height was zero. Big sheets with lots of hidden rows were slow to render i.e #108.
This update skips these by storing visible row and column indices in the view-port. The renderer then only considers those in the render loop.