eturnerx: Search results for label:twine label:"game conversions"

Showing posts sorted by relevance for query label:twine label:"game conversions". Sort by date Show all posts

2012-11-04

Joust Conversion for Twine

Here is a conversion of Joust. This is another one of those games I copied from source in a book to learn how to program as a kid. Bringing these old games back to life is like paying my dues.

This is not a difficult game - you will play through it in just a few minutes. There is also not too much in the way of flavour text compared to other games. I'd rate it as about the same as Highnoon in terms of depth but the game play feels much less varied.

SPOILER: Once you work out a winning attack / defense combo then keep repeating it and let luck do the rest.

The game logic is entirely implemented in Twine/twee code. This could've been much simplified by using custom javascript macros to handle the logic branching or even by coding a "switch...case" macro system for twine to substitute for "ON X GOTO line, line ..." code from the original. I used if, else, endif blocks and despite being a bit complicated and verbose they did handle the task well enough.

Debugging something with such tricky logic wasn't easy but I used a couple of tricks. These might be useful to other Twine/twee code authors too.

TIP1: Debug nested if, else, endif blocks by copying into another text editor and indenting like a regular programming language.
Complex nesting of if, else, endif blocks can be annoying to debug. The are formatted in non-obvious ways to suit the needs of end display, not the programming. So, just for the purposes of debugging, try indenting it as if it is a programming language.

TIP2: Debug nested <<display>> chains with html comments. e.g. <html></html>
Chasing around through multiple display macros gets hard. Add html comments to insert invisible stuff into the code so that you can inspect the page and track where the display macros are leading. It helps narrow down where the bugs are really quickly.

Checkout the other games I have converted

2012-10-07

Highnoon Conversion for Twine

This week's creative project is a conversion of Highnoon for the Twine interactive fiction system. While I was converting/reimagining for Arduino I had two thoughts. The first was that I'd like to do a more faithful conversion with the original dialogue and secondly that such a conversion would be a way to demonstrate the power of Twine.

So, you know the game; You're in a showdown with Black Bart. You each have four shells and are 100 paces apart. In this original version there are more win/loss conditions than straight death.

Twine allows quite a lot of expressiveness and flexibility when writing interactive fiction. It also outputs the results to a single .html file that require no supporting libraries or other files. If you are interested in the basics of Twine then I'd suggest looking at this tutorial.

The conversion to Twine was fairly straightforward. I used the Jonah Story Format because it places passages one after the other without clearing the screen like Sugarcane does. I made a few tweaks to the inbuilt functions; the first to totally suppress the output of passage titles and the second to totally deactivate old choices. This was not difficult; it was more a matter of removing the bits of code from existing functions that I did not need.

I also based passage names around the line numbers in the original code. This eased moving from the GOTO style of the original code to the structured coding style of Twine.

The verdict; a very playable old-style game.

Checkout the other games I have converted

2012-10-28

Camel Conversion for Twine

Here is a conversion of Camel. I can vaguely remember coding and playing this game as a kid in the early '80s. If it left that kind of impression then it must've been a fun game so I decided to give this a shot for a Twine conversion. It is similar in many ways to Highnoon in that there is an underlying game system represented by some quirky text.

The game play can be frustrating! Oases appear frequently enough that water is almost never a problem (just don't forget to drink). The biggest problem is the pygmies. They have a 10% speed advantage on your moderate speed, but running your camel at full speed burns it out three times faster.

SPOLIER: The mathematically optimal strategy is to go full speed twice, moderate speed once then rest. Drink when warned (actually the turn after). If you are captured then wait for the ransom. Even with an optimal strategy a win is not assured. In this game the player loses more often than not. Prepare for frustration.

I made extensive use of the custom macro <<randomp>> that I made for another project. This simplified a lot of the handling where things were triggered by random events.

I intentionally left as much logic in place as it is in the BASIC code with a couple of small changes. The capture submenu display the request for sub-command before the menu and the "Miles travelled" text appears more than in the original. There was also something where asking for a status report would fall through to also taking a drink. I assumed that this was a bug and changed status report to not force a drink at the same time.

From the viewpoint of 2012 the text could appear offensive. I prefer to think of it is ironically anachronistic because there are many obviously mismatched facts and intentional mispellings. Many of the other books edited by David Ahl do contain some quite detailed information about the historical context of the games so I do not assume the authors of this game were naively flavouring the game they way they did.

Checkout the other games I have converted

2012-10-22

Nicomachus Conversion for Twine

Here is a conversion of Nicomachus for Twine. This was a much simpler program than Highnoon so I further restricted myself to making all program logic happen in Twine's tweecode.

Twine surprised me with its arithmetic handling. Up until now I had been ducking into Javascript for all but the simplest of expressions. Twine was easily able to handle an arithmetic statement with three sets of parentheses and about six terms.

Twine does lack a loop function (like a while). I was able to simulate this with an if, else, endif macro that keep displaying another passage (itself) until the condition expired. You can check the code for how I implemented this. The technique is known in computer science as recursion.

The verdict; A fun quick conversion.

Checkout the other games I have converted