Show HN: Cycle-accurate Nintendo NES emulator in ~1000 lines of code | Hacker News Reader

Show HN: Cycle-accurate Nintendo NES emulator in ~1000 lines of code

github.com

20 pointsandreaorru8 comments

This is one example of how powerful and expressive C++ can be in the hands of the right person. I love (plain) C for its openness and the apparent ease of use but keep being amazed at how much more powerful as a language C++ is - to the point that C starts looking like a children's toy tool that should be abandoned as soon as the hand is strong enough to hold the real one.

Thanks (for calling me the right person). There is a price to pay for power in C++ though. Keeping the code beautiful and readable is often a challenge, as the syntax gets convoluted very quickly. I'm not the biggest fan of the Standard Template Library either.

Lately I've been experimenting with D (https://dlang.org), created by Walter Bright and Andrei Alexandrescu, both well known expert C++ programmers. D feels a lot like C++ should have been had it dropped some C compatibility in exchange for clarity. Its meta-programming capabilities are also far more powerful. I can think of features (like template mixins) that would make this project even more compact.

I'm not sure if this can be technically defined as cycle accurate, since cpu instructions are still executed atomically, instead of executing each instruction cycle independently... I guess the end result is what matters and not the actual implementation?

EDIT: I suck at c++

It's not atomical. Note that the PPU is constantly updated in the middle of the CPU instructions in a way that respects the timing of the original hardware. The relative order of operations between CPU and PPU is respected.

You're right, sorry ^^ Too many meta-programming tricks for me

This is insanely good. I remember studying the code of other NES emulators and all of them easily passed the 10k lines mark. Makes you wonder how much repeated code is there.

To be fair I don't implement all the mappers, but I'm pretty confident the core parts of the emulator (CPU and PPU) are as small as it gets.

Such pregunta. Very clever. Many condense. Such switch. WOW. So emulator.

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