A GameBoy Emulator in JavaScript? It's Possible

extremetech.com — An independent developer has published a multi-part series showing the innards of a homebrew GameBoy emulator--one that runs in JavaScript inside a browser window. Nov 9, 2010 View in Crawl 4

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A GameBoy Emulator in JavaScript? It's Possible

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Xrimfaxi Nov 10, 2010

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a real gameboy will always be much better than pc emulator))

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mattbd Nov 10, 2010

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Not really the point, though. It's more of a proof of concept.

graeh Nov 10, 2010

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impressive achievement in javascript - exactly the type of thing that would benefit from a version in actionscript 3.0. A piece comparing the development process and the end result (as well as fully compatible penetration of both) of both approaches would provide some interesting case studies.

I doubt it would surprise anyone skilled in both javascript and actionscript development - and I doubt it would be taken in to consideration by those who are skilled soley in developing javascript. Maybe I'm being pessimistic.

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graeh Nov 10, 2010

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I'll break a cardinal rule - it's obvious that it was done in javascript because it could be, being dug down for that comment irks me. And it shouldn't - but it's a good frkn overdue rarely said point about comparing js and as development and final result. Apologies for being a downvote dislking dick :D

kekusmacca Nov 10, 2010

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i miss gameboy.

moduc Nov 10, 2010

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Great tutorial. I just went over them. Maybe some people will optimise the code to make it much faster.
For example, since the program's data is treated as string, a simple utility can convert it into byte array 1 time when loading it.
Interrupt can be implemented as hook, so it's not checked every time, but if the current context is switched, the interrupt takes place, else, the main context is run.
The Javascript can be implemented more object oriented as JS objects, versus JS static classes. This can help when more than 1 emulator can be run in a single page. Also, it makes isolation better.

Some people may know better about how JS performs with various operations with regard to performance, and replace the operations with a more optimised one.

Also, I wonder if local variables are faster than JS class variables (dot notation).
So, if replacing many of those can help. I understand that those variables are referenced outside, so consideration must be made.

It's best to keep the code clean and easy to read though. So no optimisation that compromise the readability of it.