Tag Archives: gamemaker

Variable references in GameMaker

A tutorial about variable references in GameMaker.

Sometimes you might want to pass an instance variable by reference rather than by value - to have a script modify instance variable(s) passed to it without having to return them, or have an instance save a reference to variable(s) that it should change on other instance, or doing anything else that would usually imply using pointers.

But it might seem like GameMaker does not support such things... or does it? Well, we'll make it.

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2d pivot points explained

(click to interact)Explaining pivot points (mouseover/click to play GIF) (spaceship graphic by Kenney)

Nowadays, most development tools provide ways of setting pivot/center point for imagery - that is, the relative point around which the image will rotate and usually be positioned relative to.

However, ability to define multiple pivot points per image remains relatively uncommon, despite being something that you want to have projectiles fire from a correct point of a sprite, display weapons/attachements at right relative points, or do anything else that demands relative offsets.

This small post is about that.

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GameMaker: Beautifying/pretty-printing JSON

Partially related to an earlier blog post about minifying JSON (which I had just updated), but adressing a different problem - sometimes, rather than trying to make your JSON more compact (and, consequently, less readable), you may want to make it more readable - be that for your own debugging purposes, or not to scare players away from files that they are allowed to edit.

Take Nuclear Throne, for example. The save file is a big nested JSON structure, and, needless to say, you aren't getting around passing it through an external JSON beautifier if you want to be able to make sense of it:

With a bit of string processing, however, you can have it printed out nicely readable:

So this post is about that.

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Converting key code to key name and vice-versa

(click to interact)Converting key code to key name and vice-versa (mouseover/click to play GIF) Interactive demo (if JavaScript is enabled)

This is a small post about how to convert key codes to key names and/or convert key names to key codes. Comes with sample code for GameMaker and a generic version.

Mostly published because it covers majority of common and semi-common buttons.

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GameMaker: Simplest possible custom timelines

This post is about implementing custom timelines in GameMaker.

Admittedly, timelines remain to be one of the more dated features of the software, designed for a specific purpose and kept in their original form for compatibility.

Time to time you'll see someone stopping by on forums to write a big rant about how these are a mess, do not do what they expect them to do, and should be redesigned immediately.
People will usually also argue that doing these things by yourself is too hard.

Since it is far easier than people claim, I decided to write a post about this.

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