Olivier Smeesters / SoundWaveGenerator

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Dependents:   SoundWaveGeneratorTest SoundWaveGeneratorTest

Files at this revision

API Documentation at this revision

Revision 1:6864fd480178, committed 2011-02-08

Comitter:
osmeest
Date:
Tue Feb 08 21:39:55 2011 +0000
Parent:
0:ed89ef772e92
Commit message:
Fix the Sine & Triangle wave computations which were very bad !

Changed in this revision

SineWave.cpp Show annotated file Show diff for this revision Revisions of this file
TriangleWave.cpp Show annotated file Show diff for this revision Revisions of this file 
--- a/SineWave.cpp	Mon Jan 24 22:44:39 2011 +0000
+++ b/SineWave.cpp	Tue Feb 08 21:39:55 2011 +0000
@@ -9,9 +9,9 @@
     this->buffer.resize(cycleLength);
 
     std::size_t middle = cycleLength / 2;
-    std::size_t quarter = middle / 4;
+    std::size_t quarter = middle / 2;
     
-    float delta = 3.14 / (2.0 * float(sampleRate) / float(this->frequency));
+    float delta = 6.28 / (float(sampleRate) / float(this->frequency));
     for(std::size_t i = 0; i < quarter; ++i) {
         float dt = delta * i;
         float dv = std::sin(dt) / 2.0;
@@ -23,9 +23,11 @@
         this->buffer.write(cycleLength - i, negValue);
     }
     
+    this->buffer.write(quarter, 1.0);
     if (middle - quarter != quarter) {
-        this->buffer.write(quarter, 1.0);
+        this->buffer.write(middle - quarter, 1.0);
     }
+    this->buffer.write(cycleLength - quarter, 0.0);
     if (middle + quarter != cycleLength - quarter) {
         this->buffer.write(middle + quarter, 0.0);
     }

--- a/TriangleWave.cpp	Mon Jan 24 22:44:39 2011 +0000
+++ b/TriangleWave.cpp	Tue Feb 08 21:39:55 2011 +0000
@@ -8,9 +8,9 @@
     this->buffer.resize(cycleLength);
 
     std::size_t middle = cycleLength / 2;
-    std::size_t quarter = middle / 4;
+    std::size_t quarter = middle / 2;
     
-    float delta = 0.5 / (float(sampleRate) / float(this->frequency));
+    float delta = 2.0 / (float(sampleRate) / float(this->frequency));
     for(std::size_t i = 0; i < quarter; ++i) {
         float dt = delta * i;
         float posValue = 0.5 + dt;
@@ -21,9 +21,11 @@
         this->buffer.write(cycleLength - i, negValue);
     }
     
+    this->buffer.write(quarter, 1.0);
     if (middle - quarter != quarter) {
-        this->buffer.write(quarter, 1.0);
+        this->buffer.write(middle - quarter, 1.0);
     }
+    this->buffer.write(cycleLength - quarter, 0.0);
     if (middle + quarter != cycleLength - quarter) {
         this->buffer.write(middle + quarter, 0.0);
     }