consistent void* return type for data buffers

Cpp/lib/waveform.cpp

@@ -265,7 +265,7 @@ double ArrayWaveform::setMovingSegment(
     return nextPhase;
 }
 
-std::pair<int16_t*, int64_t> ArrayWaveform::getStaticWaveform() {
+std::pair<void*, int64_t> ArrayWaveform::getStaticWaveform() {
     auto minSampleLen = 2 * this->wfmParam.samplingRate
         / std::gcd(
             this->wfmParam.samplingRate,
@@ -283,13 +283,13 @@ std::pair<int16_t*, int64_t> ArrayWaveform::getStaticWaveform() {
         + this->wfmParam.phases.array())
     ).array().colwise() * this->wfmParam.amplitudes.array();
     bindBuffer(minSampleLen * 2); // bytes
-    auto pData = (int16_t*) this->pDataBuffer;
+    auto pData = (void*) this->pDataBuffer;
     Eigen::Map<EigenVectorXi16> dataMap(pData, minSampleLen);
     dataMap = wfmMatrixrix.colwise().sum().cast<int16_t>();
     return std::pair(pData, int64_t(minSampleLen));
 }
 
-std::pair<int16_t*, int64_t> ArrayWaveform::getTrickWaveform(
+std::pair<void*, int64_t> ArrayWaveform::getTrickWaveform(
     std::set<int> siteIndex,
     double df,
     double tauMove,
@@ -354,7 +354,7 @@ std::pair<int16_t*, int64_t> ArrayWaveform::getTrickWaveform(
         }
     }
     bindBuffer(sampleLen * 2);
-    auto pData = (int16_t*) this->pDataBuffer;
+    auto pData = (void*) this->pDataBuffer;
     Eigen::Map<EigenVectorXi16> dataMap(pData, sampleLen);
     dataMap = wfmMatrix.rowwise().sum().cast<int16_t> ();
     return std::pair(pData, int64_t(sampleLen));

Cpp/lib/waveform.h

@@ -225,7 +225,7 @@ class ArrayWaveform {
      * 
      * @return std::pair(pDataBuffer: int16_t*, dataLength: int64_t)
      */
-    std::pair<int16_t*, int64_t> getStaticWaveform();
+    std::pair<void*, int64_t> getStaticWaveform();
 
     /**
      * @brief generate a tricky-trick waveform from current set of
@@ -237,7 +237,7 @@ class ArrayWaveform {
      * @param tauStay wait time (s)
      * @return std::pair(pDataBuffer: int16_t*, dataLength: int64_t) 
      */
-    std::pair<int16_t*, int64_t> getTrickWaveform(
+    std::pair<void*, int64_t> getTrickWaveform(
         std::set<int> siteIndex,
         double df,
         double tauMove=0,