pretty random color for chapters

Author: OpenFunscripter

OFS-lib/OFS_Util.cpp

@@ -33,6 +33,9 @@
 #define SINFL_IMPLEMENTATION
 #include "sinfl.h"
 
+#define RND_IMPLEMENTATION
+#include "rnd.h"
+
 char Util::FormatBuffer[4096];
 
 static void SanitizeString(std::string& str) noexcept
@@ -358,3 +361,30 @@ std::filesystem::path Util::FfmpegPath() noexcept
     return ffmpegPath;
 #endif
 }
+
+static rnd_pcg_t pcg;
+void Util::InitRandom() noexcept
+{
+    time_t t = time(0);
+    rnd_pcg_seed(&pcg, t);
+}
+
+float Util::NextFloat() noexcept
+{
+    return rnd_pcg_nextf(&pcg);
+}
+
+uint32_t Util::RandomColor(float s, float v, float alpha) noexcept
+{
+    // This is cool :^)
+    // https://martin.ankerl.com/2009/12/09/how-to-create-random-colors-programmatically/
+    constexpr float goldenRatioConjugate = 0.618033988749895f;
+    static float H = NextFloat();
+    
+    H += goldenRatioConjugate;
+    H = SDL_fmodf(H, 1.f);
+
+    ImColor color;
+    color.SetHSV(H, s, v, alpha);
+    return ImGui::ColorConvertFloat4ToU32(color);
+}

OFS-lib/OFS_Util.h

@@ -511,6 +511,10 @@ class Util {
                 return (*pf)(decltype(args)(args)...);
             };
     }
+
+    static void InitRandom() noexcept;
+    static float NextFloat() noexcept;
+    static uint32_t RandomColor(float s, float v, float alpha = 1.f) noexcept;
 };
 
 #define FMT(fmt, ...) Util::Format(fmt, __VA_ARGS__)

OFS-lib/state/states/ChapterState.cpp

@@ -89,6 +89,7 @@ Chapter* ChapterState::AddChapter(float time, float duration) noexcept
     Chapter newChapter = {0};
     newChapter.startTime = startTime;
     newChapter.endTime = endTime;
+    newChapter.color = Util::RandomColor(0.65f, 0.90f);
 
     if(chapters.empty())
     {