ViSoft Premium is using several algorithms for tiling optimization. You can set the optimization by right clicking this button. Switch on / off the available algorithms in the right upper corner.
The quantity of whole, cut and critically cut tiles is shown in percents and presented in a bar graph. In the Preview the whole tiles are represented by green color, cut tiles are yellow and critically cut tiles are red. Green arrows on the edge represent floor / wall joint matching. Red cross means there is no match. Blue circles represent different possible starting points. You can click on any of them and check how the quantity of cut tiles has changed.
Tiling optimization can generally be switched off in the menu FILE – Preferences (tab Tiling).

You can also check the way in which the tiles are cut in 3D view. Click button 3D in Tile – Region menu. Right click on the working surface and enable 3D Settings – Highlight Selction, Tile cuts, Region and Starting points in context menu. After that left click on one of the regions in working surface. Tiles in selected region will be marked with green, yellow and red colors. Starting point of one or multiple regions if you select them by CTRL – click can be moved in 3D view too.
