Roll the cube around the grid, picking up the purple squares on its faces. Try to get all the purple squares on to the object at the same time, in as few moves as possible.
On a touch screen, a tap does what a click does.
Use the arrow keys to roll the cube, or 8, 2, 4 and 6 on the numeric keypad, or click the mouse where you want it to roll towards. After every roll, the grid square and cube face that you brought into contact swap their colors, so that a plain cube face can pick up a purple square, but a purple face rolled on to a plain square puts it down again.
On the triangular grids a triangle has one flat side, above or below it, and two sloping ones. Up or Down, whichever points at the flat side, rolls the solid across it, and Left and Right roll it across the sloping sides. The diagonal keys of the numeric keypad (7, 9, 1 and 3) make the same three rolls: the two that lean toward the flat side both cross it, and each of the other two crosses the sloping side it leans toward.
When you have mastered the cube, use the Type menu to select other regular solids!
Hint shows the next roll rather than making it. No roll in Cube is forced, so the hint plans a line of rolls that gathers every purple square onto the solid, and shows it one roll at a time. Each run of rolls ends by picking a square up, and the rolls on the way say which square that is. On the cube and the tetrahedron the line is a shortest one; on the octahedron and the icosahedron it is a good one, not always the shortest.
Two things catch everyone out, and the hint says them where they come up. A square is picked up only by a plain face, so rolling straight on to a purple square can land a purple face on it and pick nothing up: then the hint goes round to come at it another way. And a purple face rolled on to a plain square leaves its paint there. Late in the game, with most faces purple, that is often the only way on: the hint says when no square can be picked up without putting some paint down first, and when the paint it leaves is picked up again by another face. That is how paint moves from one face to another.
A purple face rolled on to a purple square changes nothing, so the hint’s line may cross purple squares on its way.
On a custom grid much larger than the ones on the Type menu, the search can run out before it finds a line, and the hint says so.
These parameters are available from the ‘Custom type…’ option on the ‘Type’ menu.