refactor: move around some code

inc/FilterFactory.h

@@ -22,4 +22,8 @@ struct FilterFactory {
         }
         return newFilter;
     }
+
+    static Filter* GetDefaultFilter() {
+        return new LowPassFilter();
+    }
 };

src/Filter.cpp

@@ -15,6 +15,7 @@ void Filter::Trigger() {}
 void Filter::Release() {}
 
 float Filter::Process(float in) {
+    // may move to a compile-time dictionary calculation, if needed
     calculate_coefficients();
     float out = in * m_a0 + m_z1;
     m_z1 = in * m_a1 + m_z2 - m_b1 * out;
@@ -23,10 +24,6 @@ float Filter::Process(float in) {
 }
 
 void Filter::Process(std::vector<float>& samples) {
-    // todo: that will not work for ADSR-controlled filter. So, let's calculate
-    // all the possible frequency values into array/dictionary then just lookup
-    // for each sample
-    
     for (std::size_t i = 0; i < samples.size(); i++) {
         samples[i] = Process(samples[i]);
     }

src/Renderer.cpp

@@ -241,13 +241,8 @@ float Renderer::draw_filter_panel(Synth& synth, FilterGuiState& gui_filter,
         gui_filter.is_dropdown_open = !gui_filter.is_dropdown_open;
         gui_filter.type = (FilterType)(shape_index);
         // APPLY STATE TO REAL SYNTH
-        if (!filter->IsSameFilterType(gui_filter.type)) {
-            synth.SetFilter(gui_filter.type);
-        }
-        //filter.SetType(ui_osc->waveshape);
+        synth.SetFilter(gui_filter.type);
     }
-    // if (gui_filter.is_dropdown_open)
-    //     break;
 
     // apply values to real one
     // todo: thrid (order) parameter

src/Synth.cpp

@@ -3,7 +3,6 @@
 #include "Logger.h"
 #include "OscillatorType.h"
 #include "Settings.h"
-#include "LowPassFilter.h"
 #include "FilterFactory.h"
 
 Synth::Synth(/* args */) {
@@ -11,7 +10,7 @@ Synth::Synth(/* args */) {
     add_oscillator();
     add_oscillator();
     AddEffect(new ADSR());
-    AddEffect(new LowPassFilter());
+    AddEffect(FilterFactory::GetDefaultFilter());
     for (size_t i = 0; i < STREAM_BUFFER_SIZE; i++) {
         float sample = 0.0f;
         m_out_signal.push_back(sample);
@@ -98,7 +97,9 @@ void Synth::AddEffect(Effect* fx) { m_effects.push_back(fx); }
 
 void Synth::SetFilter(FilterType type) {
     Filter* oldFilter = this->GetFilter();
-    Filter* newFilter = FilterFactory::CreateFilter(oldFilter, type);
-    delete oldFilter;
-    m_effects[1] = newFilter;
+    if (!oldFilter->IsSameFilterType(type)) {
+        Filter* newFilter = FilterFactory::CreateFilter(oldFilter, type);
+        delete oldFilter;
+        m_effects[1] = newFilter;
+    }
 }