The New Sudoku Players' Forum

[sudokumaster]

Hey wonderful sudoku players.

I know there are plenty of available sudoku apps and websites, but most of them fall in one of three categories:

1. Over the top commercial (ads, popups, videos)
2. Too simplistic (very easy puzzles or little configuration)
3. Ugly or not usable on a mobile phone

I'm thinking to change that by creating a sudoku game, which is pleasant to play, configurable, and doesn't have visual distractions. I have my list of requirements, but creating a game just for myself is silly, so I want to ask you what makes a good game.

What are the best features/settings you saw in sudoku games?
What bothers you in the game you usually play?
Are there scenarios when you would like to play sudoku, but the game isn't available?
What are the great examples I can learn from?

Thanks a lot!

[sudokumaster]

It's sad for me to see so little interest to have an alternative, more configurable and available offline sudoku game.

I still think it's a good idea to continue and build the app. If some of you are curious, check my progress with the game on https://soodoku.com.

It's an early stage of development, I need to think about the mistakes (e.g. set the limit), undo options, show game stats, add share option, and work on details, but you can already see the direction. If you enjoy the game, please let me know. And if you dislike it, or spot a problem, please also add a comment or send me a DM.

[Hajime]

Pretty slick interface. Well done.
What I miss:
- a "show all remaining candidates" button that shows all pencil marks in each unsolved cell.
- when clicking on a solved cell all cells with that number are highlighted, including cells with candidates. Nice. To eliminate a candidate, say 9, I click on the lower row button with a little 9. It show up. Click again and the candidate 9 will disappear, but the cells remains highlighted. How to eliminate the candidate 9?

[sudokumaster]

Hey Hajime,

Thanks a lot for checking and providing me your feedback. I really appreciate it.

I'm actually working on the first feature right now. The update is coming in the next couple of days.

The algorithm to show remaining candidates is simple, what's complex is: to overwrite existing cells with partial presence of candidates or not. Many sudoku games overwrite cells with some candidates, and it annoys me when cells with naked pairs become cells with variety of options & naked pairs are lost. Aiming to make the game fully configurable, maybe I should leave it up to the player to decide to fill the cells with notes or leave them untouched.

Another complexity for me are two types of visual hints: before cells are filled with candidates I like to see the overlapping areas (same row, same column, same box, etc), but after the candidates are filled, I prefer to see accents on naked & hidden singles/pairs/triplets. So I'm trying to find an elegant way to make all this work without overloading the interface.

About the second point, if I understood you correctly, you added a few candidates, but as you progress in the game, you need to eliminate some of them. You remove candidates the same way as you add them: by clicking on the corresponding button in the bottom row or pressing Shift + number (on US keyboard for now). They can be auto-removed when you fill a cell with the same value in the row/column/box of the candidate. Doesn't this work? Or the problem is that the numbers 9 from your example remain highlighted after the candidate is removed? I see pros & cons of this behaviour, so I might add an option to configure this as well.

[Hajime]

Great and yes I meant: Or the problem is that the numbers 9 from your example remain highlighted after the candidate is removed
Also another issue: The difficulty of a puzzle is not determined by the count of the givens....

[sudokumaster]

Hey Hajime,

Thanks for the context. I released a new version of the game with a few updates, one of them hopefully addressed the problems you mentioned: ability to fill the candidates at the beginning of each game and during the game, plus the ability not focus on the values you remove from candidates. I made a single toggle in the settings which changes the game from a classic sudoku (no pencil marks) to a game where you need to illuminate impossible candidates, each type with its own set of hints. All hints are configurable, so you can switch between two opposite game styles in the middle of a game.

On your last point about game complexity, indeed the number of clues is not a good representation of the complexity. The fair complexity estimation requires a different algorithm, which is difficult to implement in a game that works fully offline. If puzzles are generated on your device, not all puzzles will satisfy your complexity needs, so the easiest way out is to proxy the complexity to the number of clues. I'll work on the more accurate way of adjusting game complexity in the coming weeks.

Thanks a lot for your comments, and I would very much appreciate your feedback about the recent changes.

Cheers!

[Hajime]

Looks great. All my first wishes are implemented. Good job.
I solved a medium with singles only.
I will try the more difficult ones in the next days.

I tried an extreme... Made an error . Where is the undo button?
I had to restart the same game. Ok.
Now I saw the red and orange naked/hidden singles pencilmarks. Great.
Solved it with singles...

[sudokumaster]

Bravo!

Thanks for the feedback.

Yes, the undo button is in my plans, for now undo is pressing the same button once more (pressing "9" once adds "9", pressing it twice removes it), but I agree it's not obvious.

At the moment the whole error handling can be done much better (error counting, blocking next moves if there are errors, etc). I'll work on this after making more contrast dark & light themes.

[Hajime]

...the undo button is in my plans, for now undo is pressing the same button once more (pressing "9" once adds "9", pressing it twice removes it)...

Ok, but about 5 or 6 turns ago I made the mistake and I forgot the sequence of turns

[sudokumaster]

Yes, you're absolutely right.

I also noticed that when I made a wrong move having a lot of candidates prefilled, and the wrongly placed number removed a lot of candidates in the overlaping areas. I was able to undo the mistake immediately, but this didn't restore the removed candidates. So undo will be one of the next things I'll add.

Thanks for your attention to this.

[sudokumaster]

Hey Hajime. It took me some time, but I finished the work on the undo button. It plays nicely with both versions: classic & pencil notes. The undo button appears only when the first move is made, so it takes the place of info button, which I'm planning to use for all kind of tips and technique explanations.

Also, I added a couple of new themes. I think the visual delight is equally important as the gameplay.

Next plans: sharing & restoring puzzles, usage statistics, additional performance optimizations for offline usage.

Looking forward to getting your feedback!

[Hajime]

Hi sudokumaster
Very well programmed. I like the interface.
Looking forward to the import/export of puzzles.

At this version naked/hidden pairs/triples (in "Highlight Notes") are highlighted, but there are many more methods.
How do you cope with that challenge?

Further the difficulty of a puzzle is not determined by the number of clues.
As an example see this link http://forum.enjoysudoku.com/patterns-game-results-t6291-450.html
It shows a list of puzzles with the same layout and the same number of givens.
Each puzzle is on one line of 81 digits and a difficulty score.
The first is very easy. The last is "undoable". And everything in between.