PyTAS allows for the more than just the simulation of the growth of tile assemblies. Tile assemblies can be loaded, 2D assemblies can be manually created and edited, and assemblies can be saved.
A tile assembly that has previously been created or saved can be loaded into the simulation window using the menu option "File" -> "Load assembly...". Note that this will only load the selected ".tdp" file, so the associated tile set will need to already be loaded. To automatically load the corresponding ".tds" file too, use the option "File" -> "Load system (seed and tile set)...".
In order to manually add and remove tiles, click the tool bar button "Tile Add/Remove Mode", which will activate the assembly editing mode. In this mode, right-clicking on an empty location in the assembly space will bring up a window which will allow you to select a tile type (from the currently loaded tile set) so that a tile of that type will be placed in that location. Right-clicking on a location which already has a tile will present a window which will allow you to delete the tile from the assembly.
After any number of assembly steps, a simulation can be reset to the seed assembly using the menu option "File" -> "Reset to Seed", or by pressing 'r'. In order to ensure that the exact same assembly sequence will be followed if simulation is started over, do not change the random seed value in the dialog which is displayed. If you would instead like to enable a different assembly sequence to be followed, you must change the value of the random seed.
While an assembly can be saved at any time (meaning after any number of tile additions, or simulation steps), whenever it is subsequently loaded it will be treated as a seed assembly. An assembly can be saved using the menu option "File" -> "Save assembly".
PyTAS can load a tile set into the simulation window and another (or separate copy) into the tile type editor window. This allows you to run simulations with the tile set loaded into the simulator and also to edit a tile set in the editor and then only load the changed tile set into the simulation window when you choose.
A tile set can be loaded into the simulator window by: (1) loading just the tile set from a file (e.g. using "File" -> "Load tile set..."), or (2) loading a full tile assembly system from files, or (3) loading the tile set from the tile type editor window (e.g. "File" -> "Load tile set from editor").
Creating and Editing Tile Sets
Tile sets can be created and edited in the tile type editor window. Double-clicking on a tile will select it for editing in the tile type window. Right-clicking in the main editor pane will allow you to create new tile types, duplicate tile types, and delete existing tile types.
Tile sets can be saved to files from either the tile type editor window or the simulation window. Note that the tile set which is loaded in the window which is used to save it is the one that will be saved to the file.