Posts Tagged struct

C++ Scripting: Part 17 – Boxing and Unboxing

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The GitHub project is closing in on supporting all the “must have” features. Today’s article tackles “boxing” and “unboxing” so our C++ game code will be able to convert types like int into an object and then convert an object back into an int. Usually we want to avoid this because it creates garbage for the GC to later collect and ruins type safety, but sometimes an API like Debug.Log insists that we pass it an object. Read on to see how to use boxing and unboxing in C++!

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C++ Scripting: Part 11 – Collaborators, Structs, and Enums

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The series to build a viable system to write Unity scripts in C++ continues! While these 11 articles have covered a lot of ground toward making a usable C++ scripting system, there’s still a lot to do. Writing the code for these articles takes quite a lot of time, so today I’m officially calling for collaborators on the GitHub project. If you’d like to join in, please leave a comment, send an e-mail, or submit a pull request. There’s plenty to do and your help would be greatly appreciated! Aside from that, today’s article is all about adding support for struct and enum types so we can use types like Vector3 and TextureFormat from our C++ scripts.

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Getting the Size of a Struct at Compile Time

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I continue to learn a lot by reading the C++ code that IL2CPP outputs. Like reading decompiled code, it gives some insight into what what Unity’s build process is doing with the C# we give it. This week I learned that sizeof(MyStruct) isn’t a compile-time constant like it is in C++. Because of that, IL2CPP generates some less-than-ideal C++ code every time you use it. Today’s article shows the process I went through to work around that issue and ends up with some code you can drop into your project to avoid the problem.

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Three Surprises I Encountered While Reading IL2CPP Output

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We code in C#, but that’s just a starting point. Our C# code is compiled to DLLs and then converted into C++ where it’s compiled again to machine code. The good news is that this isn’t a black box! I’ve recently been reading through the C++ code that IL2CPP outputs and learning quite a lot. Today’s article is about some of the surprises that I encountered and how you can change your C# code to avoid some nasty pitfalls.

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Making Structs More Useful with Object Handles

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Structs can be a great way to keep the garbage collector off your back and to use the CPU’s data cache more effectively. Not everything can be a struct though. At a minimum, you’ll need to use some Unity and .NET classes like MonoBehaviour and string. If your struct has any of these as fields, you can no longer use sizeof(MyStruct). That really limits its usefulness, so a workaround is needed. Enter object handles: a simple way to represent any object as a plain old int which won’t break sizeof. Read on to see how these work and some code you can easily drop into your project to start using them right away!

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The Other CPU Cache

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We’ve seen how using the CPU’s cache can lead to a 13x speedup, but that’s only utilizing one of the CPU’s cache types. Today’s article shows you how to go further by utilizing a whole other type of CPU caching!

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How to Use the Whole CPU

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Last week’s article showed how to effectively use the CPU’s caches to boost performance by an order of magnitude. Today’s article goes even further to show you how to use even more of the CPU’s capabilities!

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How to Write Faster Code Than 90% of Programmers

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Most programmers write code for an abstract computer. The thing is- code runs on a real computer that works in a specific way. Even if your game is going to run on a wide range of devices, knowing some of the common features can speed up your code 10x or more. Today’s article shows you how!

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Enumerables Without the Garbage: Part 7

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Today we’ll wrap up the iterator series by finishing up porting C++’s <algorithm> header. We end up with a library of functions for common LINQ-style algorithms but without any of the garbage creation that slows our games down. Read on for the source and examples!

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Enumerables Without the Garbage: Part 6

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We’re nearing the end of the series to build a no-garbage replacement for System.Linq. Today we tackle functions that work on already-sorted ranges and functions that work on ranges that are in heap order. These include common set operations like “union” and “intersection”. Read on to see how to use them and for the updated library that you can use to eliminate your garbage creation!

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