The Happy Cube Solver is a very friendly to use and intuitive application. After you start the application, you are faced with the structure design interface and its accompanying sidebar:
The initial structure displayed in the black the design area is a single one-by-one-by-one cube and the initial piece selection is the entire Happy Cube (plain color) set of pieces. pressing the "Solve It!" button on the side-bar at this stage will instruct the application to find a solution for the single cube structure using pieces from the plain Happy Cube set.
A few seconds after pressing the "Solve It!" button a soultion will appear and you will be able to rotate it in space and build it with your physical Happy Cube pieces.
To return to the design interface, press the "Design" tab in the sidebar.
The design interface allows you to create any shape imaginable and give it form using Happy Cube pieces. The basic concept of editing structures is adding and removing cubes from the structure in 3D. At any time, you can rotate the design in space by draggin the mouse across the design area with the left mouse button pressed. To zoom in or out of the 3D display, use the slider in the bottom of the side-bar or use the mouse wheel. To add a cube, place the mouse pointer on a structure tile and double-click it. Placing the mouse pointer on a tile produces a semi-transparent blue cube which indicates where a new cube is going to be placed.
Removing a cube from the structure is just as easy. On the right side-bar press the red "Double click Removes a cube" button and then double click the cube you wish to remove. a red tint on the cubes will acompany the mouse pointer to indicate which cube is going to be removed. Notice that you cannot remove the last cube of a structure (because then there will be nothing to build upon). To go back to cube-adding mode, re-press the "Double click Adds a cube" button. While in cube-adding mode, you can quicky switch to cube-removing mode and back using the "Ctrl" button on the keyboard.
The right side-bar next to the design area allows you to roughly choose which pieces sets will be used to find a soultion for the structure. There are currently five sets of 36 pieces you can choose from. A more fine-grained selection can be achieved by pressing the "Advanced" button and selecting individual cubes or pieces of a set. In the advanced selection window, the numerical spin-box under every piece indicates how many instances of this piece are going to be using when building the solution.
To exit the advanced selection windows, simply unpress the "Advanced" button in the side bar.
Once you're created a structure in the desing interface and selected pieces for the solution, you can press the "Solve It!" button in the side-bar to instruct the application to find solutions.
Depending on the complexity of the structure and the number of selected pieces, this process can take anything between a few seconds to a number of hours. If the solver is unable to find a solution for a very long time, consider selecting more pieces for it.
When a solution is found, the application will automatically switch to the solution viewing interface where the found solution is displayed. Similar to the design interface, you can rotate the solution by dragging the mouse while the left button is pressed. While viewing a solution the right side-bar shows the pieces currently under the mouse pointer. This makes it easyer to understand the orientation of pieces in the solution.
If there is more then one solution found, you can browse between the solution using the arrows and combo-box at the bottom of the side bar. To go back to the design interface, press the "Design" tab at the top of the side bar.
All that is left to do now is to take your actual physical Happy Cube pieces and build the solution found.
There are quite a few ready made designes, some with solutions in the "Examples" directory under the main application directory. Use the File->Open menu item to open and watch them in the solver.