STPPC2x post-v1.0 update

Yes, I'm still working on it!

However, there were a few problems which meant I had trouble getting a working development environment up and running on a new machine - nothing drastic enough to stop coding but it turned from "must do" to "I'll get around to it".

Anyway, I am still coding and there's quite a few changes that have already gone into the main code repository (http://code.google.com/p/stppc2x/), but don't think that what you see in there is all that exists... I'm working on a few new features besides those listed in the previous post, it's just that it's a jumble of half-finished, specific-to-my-PC code that doesn't belong in SVN at the moment.

I won't be coding for Pandora, because STPPC2x is the only thing that I enjoy coding on recently and it would be pointless to port because Simon Tatham's original collection will run fine on it because it has full X-Windows support, but I will continue coding for the GP2X even if I'm the only person who actually uses my code! The Wiz is in a strange middle-ground... if I can get hold of one at some point, I may well port STPPC2x over provided it isn't too different from a programmatic point of view but I'm not going to buy one just to do that.

The Changelog at the SVN repository (latest version can always be found here: http://code.google.com/p/stppc2x/source/browse/trunk/CHANGELOG.GP2X ) has the lowdown on what I've finished recently (it doesn't sound very exciting!) and I still use what-will-be-v1.1 on my own GP2X when I'm out and about (I do about 3 hours of train journeys every day and take my GP2X everywhere still - perfect for beta-testing!).

It aten't dead!

STPPC2x v1.1 News

Just to reassure everyone, I'm still working on STPPC2x after my "version 1.0" release.

At the moment, I have the following in progress for "version 1.1":

Menus - Added indicators on the main menu to tell whether a game requires numeric digit input (e.g. filling, solo, unequal), supports "cursor key" control (e.g. sokoban, maze3d, etc.) or has its own solver.

Mosco - Various memory cleanups, a working "end-of-game" detector with "flash" ( so that you know you've won) - I left a bug in the version released for v1.0 that lets you complete the game even if some of the conditions aren't met.

Solo (Sudoku) - Perfect display with all the intermediate lines but in a "normal" resolution now. 4x4 sudoku is also playable because I've adjusted the "digit" input code (e.g. Press L/R to increase digit and X to enter it into a square) so that you can use the letters too... 4x4 sudoku needs 1-9, A-G, for instance.

Unequal - Because of the above, you can now play much larger unequal games too, and smaller games now only let you select numbers that are "in range" (e.g. 1 - 4 on a 4x4 unequal, 0-9 on a 10x10 unequal, 0-G on a 16x16 unequal etc.)

Loopy - New SVN updates provide better puzzle generation when using "Great Hexagonal" layouts etc.

I'm also working on a Kakuro puzzle, because it's nice to have a new puzzle each time I put out a big update.

STPPC2x Version 1.0

(Hopefully) The definitive version of my efforts to port Simon Tatham's Portable Puzzle Collection to the GP2X. This is now a set of 31 addictive logic and puzzle games (1 new to this release - Mosco). Some are old favourites (like sudoku, sliding puzzles and minesweeper) and others you may not have seen before. An awful lot has changed in this release, so make sure you read this whole thing!



You can download STPPC2x immediately from the main website or from the GP2X archive.

PLEASE NOTE: This release is a bit of a leap in how the collection operates. It is recommended that you create a new folder for this version - the directory structure has changed significantly. INI's and SAV's from previous versions are, of course, still compatible but may need a little renaming (same_game.ini to samegame.ini or rect0.sav to rectangles0.sav, etc.)

So, what's new?

- Mines now works 100%.

- New game - Mosco - written by myself, based on a puzzle I found in an old book I found lying around. There isn't a "proper" solver yet (by Simon Tatham's definition), but it will give a valid answer and determine when you have won.

- Perfect display of all games (no more mismatching lines etc.)

- Save / Load / Delete Savegame with multiple saveslots for each game.

- "Autosave" option to save whenever you come out of a game (so it gives the appearance of persistence - come out of one game, or quit the collection, and when you come back it's exactly how you left it). Off by default to prevent unnecessary writing to your SD card (hold L or R when starting a game to ignore any autosave).

- Game presets are now fully working - you can play the "difficulty levels" of games that have them, as well as create your own defaults for each individual game. (Hold L or R when starting a game from the main menu to skip your defaults, or hold L + R on the main menu to delete the config file for that game entirely).

- Music by Mr Lou is available in a (optional and seperate) "music pack" from http://www.ledow.org.uk/gp2x/ (Turned off by default - check the tracks you want to play in the Music Tracks menu and it will loop through them. Press to the left of a track name to sample it. Make sure Play Music is on and save the config on the relevant pages to get music all the time). Many thanks to Mr Lou for allowing me to use the track.

- Integrated game menu.

- Map now has an option to show "unmoveable" colours.

- New SVN version of Loopy which is much more complex and configurable. Old savegames may not be compatible (not my fault!).

- Fixed display of Solo to show up better on the GP2X.

- Screenshot feature on stick-click.

- Cursor key emulation mode (so that the D-pad/joystick) to let you play games like Sokoban easily - joystick will act like a joystick when this is turned on (indicated by a keyboard icon in the menu). Net, Light-up, Maze3D and Sokoban also support this option.

- Fix to Blackbox to allow the player to set minimum and maximum number of balls on the GP2X.

- Use the Y button in more games to support additional functions (hints, clearing digits etc.)

- A million and one other features and fixes.

Feedback is appreciated (especially from F-200 and USB mouse users) and full source code is available from:

http://www.ledow.org.uk/gp2x/

Note that this is an unofficial port - so please don't bother Simon Tatham with any problems, although he is aware of the project's existence.

Preview screenshots

More version 1.0 news

Version 1.0 Checklist - Current Status

30 fully-working games (including Mines) - Check
Perfect display of the games - Check
Loading of built-in game presets (Easy, Medium, Hard etc.) - Check
Presets menu can cope with any number of presets - Check
Saving your own custom preset for each game, with automatic loading of the preset for that game ("I like net to start on a 10x10" mode) - Check
Ability to bypass the above if you want when starting a game - Check
Blackbox fix (so you can enter, e.g. 4-10 balls instead of a fixed number) - Check
Map fix (so you can see which "countries" were given to you at the start and are therefore locked) - Check
Loopy fix (so that you can still use the "old" presets which are much more playable than the enormous presets in the new code) - Check
Up to ten save slots can be loaded, saved and safely deleted from within the game - Check
Auto-save option so that whenever you quit a puzzle it is saved in a special slot and the same puzzle in the same state greets you next time you run that game - Check
Ability to bypass the above if you want when starting a game - Check
Cursor-key emulation available for certain games (sokoban etc.)
Latest SVN (including a more complex version of Loopy) - Check
Background Music - Check
Volume control - Check
Track list (up to ten music tracks, only turn on the ones you want to play, if any) - Check
Music can be replaced by any OGG file - check
Tweaked floating-point (decimal numbers) support in some games configuration options - Check
Screenshot feature on stick click (with options to snap whole screen or just puzzle area and settings in a global settings menu to hide certain elements) - Check
Game menu can cope with any number of games - Check

Hourglass cursors, credits screens, SVN version number in the title screen, updated text throughout, general help for keys, nicer menu system, smaller executable, smaller distribution (you can even remove the music, which doesn't need to be there), and a million and one tiny tweaks - Check

Basically the only things that remain on my list for v1.0 are "Interruptible generation", a new verson of malloc() and some random code-style, duplicated variables etc. that I can prune but which don't affect the games at all.

Interruptible generation for the games which are "slow" by default (which seems to be Filling and Slide) shouldn't be too hard at all. Moving it to every game will take a bit longer as they all have different generation strategies and it'll take a while to understand the code and find the bottlenecks.

It's also a little tricky to "recover" from a interrupted generation cleanly, but it shouldn't happen too often, so that shouldn't be an issue. Mainly, it's where the game allocated a ton of memory to generate the puzzle and I missed that it should be cleaned up.

The new "malloc" (which allocates memory for the games to use) may well be implemented for v1.0 depending on how easy it is to do. The games already use a "safe malloc" within the puzzle collection for all memory allocations, which leaves the opportunity to extend it to be able to use some of the Video RAM on the GP2X too. Basically, when a "normal" memory allocation fails, it'll be able to carry on and provide a bit of Video RAM to use instead and the games won't even know the difference.

The whole procedure would be transparent to the games, but provide them with up to 32Mb of RAM extra if they need it. I can't see many current games needing it will provide a safety barrier should they touch on the 32Mb mark. I'm looking at a new game (which probably will come after v1.0 if at all) that might well come close to that mark on it's larger settings. Once you add multiple fonts, PNG's loaded into RAM, OGG files, etc. it's better to be safe for the sake of fifty lines of code.

Anyway, version 1.0 is iminent and in a more-than-releaseable state as it is. I just want to playtest some more (the wife is very good at finding bugs accidentally), get those two more bits of code in and then it'll be released.

Feature-creep

Okay, so version 1.0 is slowly taking shape. Here's a few snippets of the smaller parts that are being worked on in between a lot of the "big stuff".

Firstly, there's a couple of things that I've put in there for my own use. For instance, there's screenshot code now, although probably the only person that will use that is myself. It's BMP-only (converting to PNG using libpng just looks way too complex to bother with) and I use it to verify the drawing is correct, to build the new animated GIF's for advertising the game and things like that. Unfortunately, because it needs to be able to activate at any time, this is one of those features that can't be slowly moved into the menus like almost every other new feature and requires a dedicated key. I've put it on Stick-Click for now because most people never press it (and it doesn't even exist on later versions of the GP2X), so it won't get in people's way.

It highlights a big problem that I have - the GP2X doesn't have enough keys! Unbelievable, I know! Excluding the basic up-down-left-right (whether as a "mouse" or "cursor keys") that are common to all the games, and the key-combinations I have for "safety" (e.g. L+R to quit back to the menu etc.) the "keys" required after moving almost everything into the Pause menu are:

Left-click (required in every game)
Right-click (required in a lot of games and sometimes essential to completion / player comfort)
Middle-click (only used in a handful of the games, and not essential to puzzle completion, but convenient)
Pause / Enter Menu
Decrease Digit
Increase Digit (the only way I could make unequal, solo, filling, etc. playable without a keyboard, but still not perfect).
Enter Digit
Undo
Redo

And the buttons I have are: A, B, X, Y, L, R, Select, Start. 8 buttons for 9 functions. So before release I'll be re-jigging all the keys. I don't want to move Undo/Redo into the menus but it's an option. I also don't want to shift a common key into a "combination" (e.g. at the moment I have L+VolDown for Undo and L+VolUp for Redo). I'd also like a key to switch between input systems eventually, so that for some games where it makes more sense to use a "cursor-control" system instead of a mouse-emulation one (such as fifteen and sokoban), the user can change between them at the press of a button.

Some "hidden" combinations need to be present to. Because the user can save their favourite configuration for each game as a preset, and that preset loads by default whenever they start that game, there needs to be a way to cope with two scenarios: The config save file gets corrupted, the config describes a game which takes an inordinately long time to generate. Imagine accidentally saving a config for Net, for example, that takes an hour to generate a game. You'd have to leave your GP2X on for all that time before you'd be able to change the options and play Net normally again. In fact, the easy solution is a little hidden feature - press L or R when loading a game from the main menu and it will completely ignore your preset. You can then get into the game ultra-quickly, change the options and re-save your preset if you need to.

At the moment, the options in the Pause menu are so numerous that they are now sub-categorised:

New Game
Restart Game
Solve Game
Configure Game
- View Presets
- Load "My Preset"
- {Load Preset X}
- {Configuration Option X}
- Save As "My Preset"
Help
- General help (Keys, etc.)
- {Game X} Instructions
- {Game X} Tips and Tricks
Global Options
- Music
- Track List
- Volume (including On/Off)
- Auto-Save Game on Exit
- Screenshots
- Include cursor in screenshot.
- Include status text in screenshot.
Credits & Licenses
- Puzzle Collection
- Third-party Games
- GP2X Port
- Music
Quit to Main Menu (the list of games).

I have decided on the background music I want and got permission of the artist - by strange coincidence, they own a GP2X so they'll be able to play the game with their own music. I've gone for some plinky-plonky ambient music - gentle, relaxing, simple. I'll also retain the ability for the users to replace or remove the music if they so wish - it'll just be 10 OGG files in a music folder. If they aren't there, nothing plays. If they are, they appear on a track list that the user can edit - so even if they don't like my choices, they can choose their favourite tracks to play while they puzzle. And, of course, there's the all important "Music Off" option.

General Updates:

The main menu shows the revision of STPPC that they are based on. This is so that people can see how old the collection is and whether it needs updating to support feature X of a certain game, or indeed any new games that come about. (There's a new, much more configurable, version of Loopy in SVN and it's already in my private version of 1.0 and working perfectly.)

The main menu is now complete and allows loading any of the 30 fully-working games (yes, 30, because Mines works now). It lets you go into and come out of the games as many time as you like without quitting back to the menu and is super-fast. I tried it on my GP2X for a laugh and after 200 entries and exits from particular games without quitting back to the main menu, I was suitably satisifed that I wasn't leaking too much RAM or risking a crash by playing that many games - this test included music, games with saved presets, full games, partial games, games with timers, loading/saving games, etc. A fairly accurate measurement of memory usage says that (with music off) the games rarely go about 5Mb of allocated RAM in their default configurations, although obviously most of them can be allowed to grow to silly sizes if you play with their config options. Without going too mad, I was able to generate "virtually impossible to solve within the GP2X's battery life" puzzles in all the games and didn't once get an out-of-memory error or crash. Although some of them nearly took forever to generate puzzles of that size!

Music works but may stutter on very difficult puzzle generation. There's not much I can do about this without increasing the size of the sound buffer - at the moment puzzle generation is an inherently single-threaded process and it tends to swamp the CPU and all other threads running. When interruptible generation is implemented (a BIG task), then it will hopefully solve itself because in the same place that I put code to check if the user wants to stop, I can refresh the music buffer.

I also know that Blackbox has a configuration option that can take values of the form "4-10" meaning "anything from 4 to 10". That's totally impossible to enter in the options menu in the current state (although you can happily use a Preset or hand-edited config file to play it!), but I may well hack on the Blackbox code to convert this to two configuration options: Min and Max. If you set them to the same number N, it's the same as just "N" in the config box, and if you set them to, say, X and Y respectively, it's the same as entering "X-Y" in the config box. I'll also be on the lookout for other similar options that allow such things.

Config-options are one of those things that are really finicky to convert to a non-keyboard device because they are expecting textual input all the time - the current GP2X code has always had a special "Kludge" switch that allows entry of floating-point numbers in, for example, "Barrier Probability" in net because otherwise you'd only have barriers everywhere or none at all. At the moment, such options are hard-coded in the GP2X code but I'm trying to find a nice way for the puzzles to support telling the so-called "frontend" whether a configuration option should be floating-point or not. It looks like I might have Simon Tatham's ear on that particular issue, however.

There's been a massive reorganisation of the files that the program uses. The folder structure is currently similar to:

Configurations/ (holds the game-specific INI files)
Documentation/ (holds various information about the collection such as licenses etc.)
Help/ (holds the various help textfiles)
Images/ (holds splashscreens and "game previews" that show in the menu)
Images/Screenshots/ (holds any generated .BMP screenshots)
Music/ (hold, erm, the music?)
Saves/ (holds all the savegames)
STPPC2x.gpe

So hopefully, there will be no more hundreds-of-files-in-one-folder and even the above folders should be as empty as they can be.

Finally (for this update at least), I'm looking at making a new game to go into the collection. It won't make it into the official collection, I'm sure, but I'm looking at the possibility of a simple overhead 2D maze game - I have some code that I can use for various "types" of mazes and solvers for them and I'm hoping they'll translate well to the small screen of the GP2X. That will be probably be a post-1.0 thing, though, because believe it or not, programming for that side of the collection is new to me!

STPPC2X - "Mines" is now working!

Ah-ha!

Right, FINALLY. I got you, you mines-bast**d. FIXED. FIXED. FIXED. Version 1.0 will have working "mines"! Guaranteed.



Okay, for some reason, the particular version of gcc on ARM that the Open2x development environment uses does not treat an relatively-undocumented (and technically "broken") use of memset on the ARM platform the same as it does on x86. I think it's the alignment of ARM but I can't be bothered to check the exact technical details know that I have found it.

void * memset ( void * ptr, int value, size_t num);
Sets the first num bytes of the block of memory pointed by ptr to the specified value (interpreted as an unsigned char).

Notice the "unsigned char" bit. So when you do what mines.c was doing: memset(a pointer, -2, a number) it works perfectly on x86 (and all the other supported platforms, including MacOS, Palm, etc.) but does this on ARM:

"-1 -2 -2 -2 -1 -2 -2 -2 -1 -2 -2 -2"

Which buggers up mines! The fix is not to use memset but to fill the array manually - you get the proper result and mines no longer crashes but "just works". There were three places, only in mines.c, that do similar things. It seems to work fine for the other uses which are mostly -1's.

This fix was found by the following method:

1) Write original author of mines.c a long begging letter with lots of technical details on the problem
2) Recieve reply with basically says "No idea, can you print out the contents of X at line Y for me to look at?"
3) Edit code to print out contents of X at line Y on both PC and GP2X.
4) Gather debug logs from both platforms and compare.
5) Draft another long begging letter which says "This is what I got".
6) Just before hitting Send with large debug logs attached, notice that there is a pattern to the what-should-be-empty array.
7) On a hunch, gradually keep shifting the debug check higher and higher in the code, eventually placing it immediately after a memset.
8) Spot the problem (memset arrays aren't actually uniformly memset)
9) Google the definition of memset which includes the "unsigned char" line.
10) BELLS RING.
11) Search for all memsets with negative parameters and replace with for() loops.
12) Test on PC and GP2X.
13) Rewrite email to Simon Tatham, including a patch and problem description and press Send.
14) Kick self repeatedly and hard.

Anyway... it's fixed. Mines works. Finally. Can't believe it was something so stupid. Multiple human error, because obviously nobody who's touched the mines code had ever noticed the error before and only a compile on an ARM-based device showed it up. Patch winging its way to Simon Tatham for inclusion in the main code. Sigh of relief. Celebration game of mines.

Now, who's got the champagne?