ms to sound byte position utility function

Raffaello · Nov 12, 2023 · 88ff32e · 88ff32e
1 parent 16cfd08
commit 88ff32e
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Showing 3 changed files with 33 additions and 0 deletions.
diff --git a/sdl2-hyper-sonic-drivers/src/HyperSonicDrivers/utils/sound.cpp b/sdl2-hyper-sonic-drivers/src/HyperSonicDrivers/utils/sound.cpp
@@ -71,4 +71,14 @@ namespace HyperSonicDrivers::utils
 
         return  ms * 1000 / sound->freq;
     }
+
+    uint32_t ms_toPos(const uint32_t ms, const std::shared_ptr<audio::PCMSound>& sound)
+    {
+        uint32_t res = ms * sound->freq / 1000;
+
+        if (sound->stereo)
+            res <<= 1;
+
+        return res;
+    }
 }
diff --git a/sdl2-hyper-sonic-drivers/src/HyperSonicDrivers/utils/sound.hpp b/sdl2-hyper-sonic-drivers/src/HyperSonicDrivers/utils/sound.hpp
@@ -26,4 +26,5 @@ namespace HyperSonicDrivers::utils
         const std::shared_ptr<audio::PCMSound>& sound2);
 
     uint32_t duration_ms(const std::shared_ptr<audio::PCMSound>& sound);
+    uint32_t ms_toPos(const uint32_t, const std::shared_ptr<audio::PCMSound>& sound);
 }
diff --git a/sdl2-hyper-sonic-drivers/test/HyperSonicDrivers/utils/TestSound.cpp b/sdl2-hyper-sonic-drivers/test/HyperSonicDrivers/utils/TestSound.cpp
@@ -81,6 +81,28 @@ namespace HyperSonicDrivers::utils
         EXPECT_EQ(duration_ms(s4), 11025);
         EXPECT_EQ(duration_ms(s5), 5512);
     }
+
+    TEST(utils, ms_toPos)
+    {
+        const uint32_t size = 44100 * 2;
+        auto data = std::make_shared<int16_t[]>(size);
+
+        auto s1 = std::make_shared<PCMSound>(eChannelGroup::Plain, true, 44100, size, data);
+
+        EXPECT_EQ(ms_toPos(0, s1), 0);
+        EXPECT_EQ(ms_toPos(1000, s1), 44100 * 2);
+        EXPECT_EQ(ms_toPos(500, s1), 22050 * 2);
+        EXPECT_EQ(ms_toPos(250, s1), 11025 * 2);
+        EXPECT_EQ(ms_toPos(100, s1), 4410 * 2);
+
+        auto s2 = std::make_shared<PCMSound>(eChannelGroup::Plain, false, 44100, size, data);
+
+        EXPECT_EQ(ms_toPos(0, s2), 0);
+        EXPECT_EQ(ms_toPos(1000, s2), 44100);
+        EXPECT_EQ(ms_toPos(500, s2), 22050);
+        EXPECT_EQ(ms_toPos(250, s2), 11025);
+        EXPECT_EQ(ms_toPos(100, s2), 4410);
+    }
 }
 
 int main(int argc, char** argv)