Add Pre-Delay

1 files changed, 37 insertions, 0 deletions

diff --git a/src/DSP/Delay.cpp b/src/DSP/Delay.cpp
new file mode 100644
index 0000000..50c310a
--- /dev/null
+++ b/src/DSP/Delay.cpp
@@ -0,0 +1,37 @@
+#include "Delay.h"
+
+void
+Delay::prepare(double sampleRate, int samplesPerBlock)
+{
+    int maxDelayTimeMs = 2000;
+    int maxDelaySamples = static_cast<int>(sampleRate * maxDelayTimeMs / 1000.0);
+
+    delayBuffer.resize(maxDelaySamples, 0.0f);
+    std::fill(delayBuffer.begin(), delayBuffer.end(), 0.0f);
+    delayBufferWritePos = 0;
+    this->sampleRate = sampleRate;
+}
+
+void
+Delay::process(float& sample)
+{
+    if (delayInSamples == 0)
+    {
+        return;
+    }
+    int delayBufferLength = (int)delayBuffer.size();
+    int delayReadPos
+        = (delayBufferWritePos - delayInSamples + delayBufferLength) % delayBufferLength;
+    float delayedSample = delayBuffer[delayReadPos];
+
+    delayBuffer[delayBufferWritePos] = sample;
+    sample = delayedSample;
+
+    delayBufferWritePos = (delayBufferWritePos + 1) % delayBufferLength;
+}
+
+void
+Delay::setDelayMs(float ms)
+{
+    delayInSamples = static_cast<int>(sampleRate * (ms / 1000.0f));
+}