Merge pull request #462 from jpcima/loopfix

Fix the case when multiple loops occur in one buffer

src/sfizz/MathHelpers.h

@@ -139,6 +139,20 @@ constexpr T clamp(T v, T lo, T hi)
     return max(min(v, hi), lo);
 }
 
+/**
+ * @brief Compute the floating-point remainder (fmod)
+ *
+ * @tparam T
+ * @param x
+ * @param m
+ * @return T
+ */
+template <class T>
+inline constexpr T fastFmod(T x, T m)
+{
+    return x - m * static_cast<int>(x / m);
+}
+
 template <int Increment = 1, class T>
 inline CXX14_CONSTEXPR void incrementAll(T& only)
 {

src/sfizz/Voice.cpp

@@ -549,12 +549,12 @@ void sfz::Voice::fillWithData(AudioSpan<float> buffer) noexcept
 
     if (region->shouldLoop() && region->loopEnd(currentPromise->oversamplingFactor) <= source.getNumFrames()) {
         const auto loopEnd = static_cast<int>(region->loopEnd(currentPromise->oversamplingFactor));
-        const auto offset = loopEnd - static_cast<int>(region->loopStart(currentPromise->oversamplingFactor)) + 1;
+        const auto loopStart = static_cast<int>(region->loopStart(currentPromise->oversamplingFactor));
-        for (auto* index = indices->begin(); index < indices->end(); ++index) {
+        const auto loopSize = loopEnd + 1 - loopStart;
-            if (*index > loopEnd) {
+        for (auto* it = indices->begin(), *end = indices->end(); it < end; ++it) {
-                const auto remainingElements = static_cast<size_t>(std::distance(index, indices->end()));
+            auto index = *it;
-                subtract1<int>(offset, { index, remainingElements });
+            *it = (index < loopEnd + 1) ? index :
-            }
+                (loopStart + (index - loopStart) % loopSize);
         }
     } else {
         const auto sampleEnd = min(