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neogeekneogeek
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Added ReadMidiFile method.
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‎RhythmGameUtilities.Tests/MidiTest.cs‎

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using System.IO;
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using NUnit.Framework;
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namespace RhythmGameUtilities.Tests
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{
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public class MidiTest
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{
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[Test]
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public void TestReadMidiFile()
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{
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var directory = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
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var path = Path.GetFullPath(Path.Combine(directory, "../../../Mocks/song.mid"));
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var notes = Midi.ReadMidiFile(path);
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Assert.That(notes.Count, Is.EqualTo(10));
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Assert.That(notes[0].Position, Is.EqualTo(0));
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Assert.That(notes[0].HandPosition, Is.EqualTo(48));
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Assert.That(notes[1].Position, Is.EqualTo(480));
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Assert.That(notes[1].HandPosition, Is.EqualTo(50));
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Assert.That(notes[2].Position, Is.EqualTo(960));
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Assert.That(notes[2].HandPosition, Is.EqualTo(52));
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Assert.That(notes[3].Position, Is.EqualTo(1440));
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Assert.That(notes[3].HandPosition, Is.EqualTo(54));
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Assert.That(notes[4].Position, Is.EqualTo(1920));
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Assert.That(notes[4].HandPosition, Is.EqualTo(56));
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Assert.That(notes[5].Position, Is.EqualTo(2400));
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Assert.That(notes[5].HandPosition, Is.EqualTo(48));
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Assert.That(notes[6].Position, Is.EqualTo(2400));
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Assert.That(notes[6].HandPosition, Is.EqualTo(50));
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Assert.That(notes[7].Position, Is.EqualTo(2400));
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Assert.That(notes[7].HandPosition, Is.EqualTo(52));
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Assert.That(notes[8].Position, Is.EqualTo(2400));
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Assert.That(notes[8].HandPosition, Is.EqualTo(54));
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Assert.That(notes[9].Position, Is.EqualTo(2400));
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Assert.That(notes[9].HandPosition, Is.EqualTo(56));
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}
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}
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}

‎RhythmGameUtilities.Tests/Mocks/song.mid‎

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‎RhythmGameUtilities/Scripts/Midi.cs‎

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using System;
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using System.Collections.Generic;
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using System.Runtime.InteropServices;
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namespace RhythmGameUtilities
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{
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internal static class MidiInternal
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{
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[DllImport("libRhythmGameUtilities", CallingConvention = CallingConvention.Cdecl)]
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public static extern IntPtr ReadMidiFileInternal(string filename, out int size);
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}
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public static class Midi
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{
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public static List<Note> ReadMidiFile(string path)
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{
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var notes = new List<Note>();
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var ptrArray = MidiInternal.ReadMidiFileInternal(path, out var size);
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var noteSize = Marshal.SizeOf(typeof(Note));
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for (var i = 0; i < size; i += 1)
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{
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var noteSizePtr = new IntPtr(ptrArray.ToInt64() + noteSize * i);
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var note = Marshal.PtrToStructure<Note>(noteSizePtr);
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notes.Add(note);
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}
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Marshal.FreeHGlobal(ptrArray);
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return notes;
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}
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}
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}

‎UnityPackage/Editor/Tests/MidiTest.cs‎

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using System.IO;
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using NUnit.Framework;
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namespace RhythmGameUtilities.Tests
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{
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public class MidiTest
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{
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[Test]
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public void TestReadMidiFile()
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{
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var directory = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
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var path = Path.GetFullPath(Path.Combine(directory, "../../../Mocks/song.mid"));
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var notes = Midi.ReadMidiFile(path);
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Assert.That(notes.Count, Is.EqualTo(10));
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Assert.That(notes[0].Position, Is.EqualTo(0));
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Assert.That(notes[0].HandPosition, Is.EqualTo(48));
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Assert.That(notes[1].Position, Is.EqualTo(480));
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Assert.That(notes[1].HandPosition, Is.EqualTo(50));
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Assert.That(notes[2].Position, Is.EqualTo(960));
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Assert.That(notes[2].HandPosition, Is.EqualTo(52));
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Assert.That(notes[3].Position, Is.EqualTo(1440));
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Assert.That(notes[3].HandPosition, Is.EqualTo(54));
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Assert.That(notes[4].Position, Is.EqualTo(1920));
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Assert.That(notes[4].HandPosition, Is.EqualTo(56));
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Assert.That(notes[5].Position, Is.EqualTo(2400));
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Assert.That(notes[5].HandPosition, Is.EqualTo(48));
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Assert.That(notes[6].Position, Is.EqualTo(2400));
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Assert.That(notes[6].HandPosition, Is.EqualTo(50));
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Assert.That(notes[7].Position, Is.EqualTo(2400));
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Assert.That(notes[7].HandPosition, Is.EqualTo(52));
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Assert.That(notes[8].Position, Is.EqualTo(2400));
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Assert.That(notes[8].HandPosition, Is.EqualTo(54));
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Assert.That(notes[9].Position, Is.EqualTo(2400));
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Assert.That(notes[9].HandPosition, Is.EqualTo(56));
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}
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}
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}

‎UnityPackage/Scripts/Midi.cs‎

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using System;
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using System.Collections.Generic;
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using System.Runtime.InteropServices;
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namespace RhythmGameUtilities
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{
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internal static class MidiInternal
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{
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[DllImport("libRhythmGameUtilities", CallingConvention = CallingConvention.Cdecl)]
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public static extern IntPtr ReadMidiFileInternal(string filename, out int size);
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}
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public static class Midi
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{
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public static List<Note> ReadMidiFile(string path)
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{
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var notes = new List<Note>();
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var ptrArray = MidiInternal.ReadMidiFileInternal(path, out var size);
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var noteSize = Marshal.SizeOf(typeof(Note));
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for (var i = 0; i < size; i += 1)
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{
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var noteSizePtr = new IntPtr(ptrArray.ToInt64() + noteSize * i);
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var note = Marshal.PtrToStructure<Note>(noteSizePtr);
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notes.Add(note);
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}
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Marshal.FreeHGlobal(ptrArray);
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return notes;
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}
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}
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}

‎include/RhythmGameUtilities/Midi.hpp‎

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#pragma once
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#include <fstream>
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#include <string>
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#include <vector>
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#include "Structs/Note.h"
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namespace RhythmGameUtilities
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{
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template <typename T> T ByteSwap(T value, int length = 8)
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{
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return (value >> length) | (value << length);
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}
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template <typename T> T ReadChunk(std::ifstream &file, int length = sizeof(T))
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{
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T chunk{};
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file.read(reinterpret_cast<char *>(&chunk), length);
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return chunk;
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}
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std::string ReadString(std::ifstream &file, int length)
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{
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std::string chunk(length, '\0');
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file.read(&chunk[0], length);
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return file.gcount() == length ? chunk : "";
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}
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uint32_t ReadVarLen(std::ifstream &file)
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{
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uint32_t value = 0;
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uint8_t byte = 0;
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do
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{
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byte = ReadChunk<uint8_t>(file);
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value = (value << 7) | (byte & 0x7F);
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} while (byte & 0x80);
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return value;
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}
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auto STATUS_NOTE_EVENT = 0x90;
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auto STATUS_META_EVENT = 0xFF;
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auto TYPE_END_OF_TRACK = 0x2F;
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std::vector<Note> ReadMidiFile(const std::string &path)
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{
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std::ifstream file(path, std::ios::binary);
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if (!file.is_open())
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{
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throw std::runtime_error("Cannot open MIDI file");
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}
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if (ReadString(file, 4) != "MThd")
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{
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throw std::runtime_error("Invalid MIDI file header");
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}
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auto headerLength = ByteSwap(ReadChunk<uint32_t>(file));
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auto format = ByteSwap(ReadChunk<uint16_t>(file));
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auto tracks = ByteSwap(ReadChunk<uint16_t>(file));
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auto resolution = ByteSwap(ReadChunk<uint16_t>(file));
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std::vector<Note> notes;
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for (int t = 0; t < tracks; t += 1)
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{
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if (ReadString(file, 4) != "MTrk")
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{
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throw std::runtime_error("Invalid track header");
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}
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auto trackLength = ByteSwap(ReadChunk<uint32_t>(file));
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uint32_t absoluteTick = 0;
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while (true)
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{
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absoluteTick += ReadVarLen(file);
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auto status = ReadChunk<uint8_t>(file);
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if ((status & 0xF0) == STATUS_NOTE_EVENT)
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{
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Note note{.Position = static_cast<int>(absoluteTick),
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.HandPosition = ReadChunk<uint8_t>(file)};
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auto velocity = ReadChunk<uint8_t>(file);
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notes.push_back(note);
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}
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else if (status == STATUS_META_EVENT)
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{
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auto type = ReadChunk<uint8_t>(file);
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auto length = ReadVarLen(file);
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file.seekg(length, std::ios::cur);
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if (type == TYPE_END_OF_TRACK)
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{
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break;
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}
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}
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else if ((status & 0xF0) == 0xC0 || (status & 0xF0) == 0xD0)
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{
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file.seekg(1, std::ios::cur);
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}
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else
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{
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file.seekg(2, std::ios::cur);
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}
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}
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}
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return notes;
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}
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} // namespace RhythmGameUtilities

‎include/RhythmGameUtilities/MidiInternal.hpp‎

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#pragma once
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#include <map>
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#include "Structs/Note.h"
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#include "Midi.hpp"
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#ifdef _WIN32
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#define PACKAGE_API __declspec(dllexport)
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#else
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#define PACKAGE_API
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#endif
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namespace RhythmGameUtilities
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{
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extern "C"
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{
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PACKAGE_API Note *ReadMidiFileInternal(const std::string &path,
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int *outSize)
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{
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auto internalNotes = ReadMidiFile(path);
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*outSize = internalNotes.size();
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auto notes = (Note *)malloc(internalNotes.size() * sizeof(Note));
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for (auto i = 0; i < internalNotes.size(); i += 1)
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{
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notes[i] = internalNotes[i];
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}
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return notes;
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}
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}
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} // namespace RhythmGameUtilities

‎include/RhythmGameUtilities/RhythmGameUtilities.cpp‎

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#include "Audio.hpp"
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#include "Common.hpp"
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#include "Midi.hpp"
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#include "MidiInternal.hpp"
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#include "Parsers.hpp"
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#include "ParsersInternal.hpp"
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#include "Utilities.hpp"

‎tests/Mocks/song.mid‎

219 Bytes
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