Posts Tagged lambda

C++ Scripting: Part 15 – Delegates

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This week’s article adds another major feature to the C++ scripting system: delegates. These are vital so C++ game code can use features like Unity’s UI system (a.k.a. UGUI). Without them, we wouldn’t be able to handle button clicks or other UI events. So read on to learn how these were implemented in the GitHub project.

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Delegates and Garbage Creation

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Two facts are at odds in Unity programming. First, delegates like Action, Func, and EventHandler are extremely common with or without events. Second, the garbage collector is a huge source of CPU spikes and memory fragmentation in our games. Why are these facts at odds? Because code that uses delegates is almost always written in a way that creates garbage. It’s an extremely easy trap to fall into, but this article will show you how to get out of it!

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Unity Function Performance Followup

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By request, today’s article follows up on my Unity Function Performance article from a year and a half ago using Unity 5.0. It adds on GameObject.SendMessage and virtual functions to get a more complete picture of how various function calls in Unity perform. Of course it runs these tests using Unity 5.4 to see if there have been any changes in the engine. Read on for the results!

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Loop Performance: Part 4

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Today’s article takes a break from the iterator series to investigate an interesting anomaly with the List.ForEach function: it’s surprisingly fast! So fast that it’s actually competitive with regular old for, foreach, and while functions. How can it be so fast when it has to call a delegate that you pass it for every single loop iteration? Read on for to find out!

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Do Events and Delegates Create Garbage?

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Unity’s garbage collector can be disastrous to our games’ framrates when it runs so we’d best not incur its wrath. We’ve seen that foreach loops usually create garbage, so the natural followup question is “what other language features create garbage?” Events and delegates are extremely handy features of C#. They serve as the function pointers and Function objects of the language. They replace signals and slots and allow for flexible callbacks. But a lot of what they do is behind the scenes. Are they creating garbage back there? Today’s article puts them to the test to see if creating and calling delegates and events creates any garbage. Read on to find out!

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How Closures Work

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C#’s support for closures includes lambdas ((a, b) => a+b) and delegates (delegate(int a, int b){return a+b;}). They’re extremely handy tools that many developers use on a daily basis. For example, it’s really convenient when using List.Find to pass in a lambda like item => item.Id == IdToFind. They also make great callbacks for asynchronous operations. However you’re using them, understanding how they work behind the scenes will help you understand how they behave and give you insight when optimizing your code. Today’s article delves into the topic to gain just this understanding, so read on to learn some more about closures!

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Unity Function Performance

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Which is the fastest kind of C# function in Unity? There are several to choose from: regular old instance methods, static methods, delegates, and lambdas. Is there any performance reason to choose one over the other? Today’s article answers just these questions by putting each type of function to the test. Read on to see which is fastest and which is slowest!

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From AS3 to C#, Part 16: Lambdas and Delegates

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Two of C#’s really interesting features are technically operators, but didn’t fit in last week’s article. These are both ways to create anonymous functions: lambdas and delegates. AS3 has anonymous functions too, but today’s article will discuss how they differ from the C# approaches. Read on to learn how to harness the power of anonymous functions in C#.

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