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How to avoid GC spikes with string formatting in Unity / .NET hot paths? [Discussion #7]

BlazorKing
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2y ago · Oct 10, 2023 8:21 PM
#1
My game loop is getting occasional micro-stutters because string interpolations $"Score: {score}" are generating garbage memory every frame. How can I format text with zero heap allocations?
BlazorKing · Full-Stack C#
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UI_Wizard
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2y ago · Oct 10, 2023 9:32 PM
#2
Use ZString or string.Create with a stackalloc Span<char>! In .NET 6+, ISpanFormattable allows writing numbers directly into a char buffer: score.TryFormat(span, out int written). Then pass the buffer directly to your renderer without creating an intermediate string.
UI_Wizard · ImGui Widget Dev
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MemoryLeaker
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2y ago · Oct 11, 2023 3:32 AM
#3
In Unity, you can also use StringBuilder with an integer-to-char conversion helper to avoid boxing.
MemoryLeaker · C++ Enthusiast
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