compressor.cpp

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{
   wxPaintDC dc(this);

   int width, height;
   GetSize(&width, &height);

   if (!mBitmap || mWidth!=width || mHeight!=height) {
      if (mBitmap)
         delete mBitmap;

      mWidth = width;
      mHeight = height;
      mBitmap = new wxBitmap(mWidth, mHeight);
   }

   wxColour bkgnd = GetBackgroundColour();
   wxBrush bkgndBrush(bkgnd, wxSOLID);

   wxMemoryDC memDC;
   memDC.SelectObject(*mBitmap);

   wxRect bkgndRect;
   bkgndRect.x = 0;
   bkgndRect.y = 0;
   bkgndRect.width = 40;
   bkgndRect.height = mHeight;
   memDC.SetBrush(bkgndBrush);
   memDC.SetPen(*wxTRANSPARENT_PEN);
   memDC.DrawRectangle(bkgndRect);

   bkgndRect.y = mHeight - 20;
   bkgndRect.width = mWidth;
   bkgndRect.height = 20;
   memDC.DrawRectangle(bkgndRect);

   wxRect border;
   border.x = 40;
   border.y = 0;
   border.width = mWidth;
   border.height = mHeight - 20;

   memDC.SetBrush(*wxWHITE_BRUSH);
   memDC.SetPen(*wxBLACK_PEN);
   memDC.DrawRectangle(border);

   mEnvRect.x = 44;
   mEnvRect.width = mWidth - 50;
   mEnvRect.y = 3;
   mEnvRect.height = mHeight - 26;

   double rangeDB = 60;

   int kneeX = (int)rint((rangeDB+threshold)*mEnvRect.width/rangeDB);
   int kneeY = (int)rint((rangeDB+threshold)*mEnvRect.height/rangeDB);

   int finalY = kneeY + (int)rint((-threshold/ratio)*mEnvRect.height/rangeDB);

   // Yellow line for threshold
   memDC.SetPen(wxPen(wxColour(220, 220, 0), 1, wxSOLID));
   memDC.DrawLine(mEnvRect.x,
                  mEnvRect.y + mEnvRect.height - kneeY,
                  mEnvRect.x + mEnvRect.width,
                  mEnvRect.y + mEnvRect.height - kneeY);

   // Was: Nice dark red line for the compression diagram
//   memDC.SetPen(wxPen(wxColour(180, 40, 40), 3, wxSOLID));

   // Nice blue line for compressor, same color as used in the waveform envelope.
   memDC.SetPen( AColor::WideEnvelopePen) ;

   memDC.DrawLine(mEnvRect.x,
                  mEnvRect.y + mEnvRect.height,
                  mEnvRect.x + kneeX,
                  mEnvRect.y + mEnvRect.height - kneeY);

   memDC.DrawLine(mEnvRect.x + kneeX,
                  mEnvRect.y + mEnvRect.height - kneeY,
                  mEnvRect.x + mEnvRect.width,
                  mEnvRect.y + mEnvRect.height - finalY);

   // Paint border again
   memDC.SetBrush(*wxTRANSPARENT_BRUSH);
   memDC.SetPen(*wxBLACK_PEN);
   memDC.DrawRectangle(border);

   // Ruler

   Ruler vRuler;
   vRuler.SetBounds(0, 0, 40, mHeight-21);
   vRuler.SetOrientation(wxVERTICAL);
   vRuler.SetRange(0, -rangeDB);
   vRuler.SetFormat(Ruler::LinearDBFormat);
   vRuler.SetUnits(_("dB"));
   vRuler.Draw(memDC);

   Ruler hRuler;
   hRuler.SetBounds(41, mHeight-20, mWidth, mHeight);
   hRuler.SetOrientation(wxHORIZONTAL);
   hRuler.SetRange(-rangeDB, 0);
   hRuler.SetFormat(Ruler::LinearDBFormat);
   hRuler.SetUnits(_("dB"));
   hRuler.SetFlip(true);
   hRuler.Draw(memDC);

   dc.Blit(0, 0, mWidth, mHeight,
           &memDC, 0, 0, wxCOPY, FALSE);
}

//----------------------------------------------------------------------------
// CompressorDialog
//----------------------------------------------------------------------------

enum {
   ThresholdID = 7100,
   RatioID,
   AttackID,
   PreviewID
};

BEGIN_EVENT_TABLE(CompressorDialog,wxDialog)
   EVT_BUTTON( wxID_OK, CompressorDialog::OnOk )
   EVT_BUTTON( wxID_CANCEL, CompressorDialog::OnCancel )
   EVT_BUTTON( PreviewID, CompressorDialog::OnPreview )
   EVT_SIZE( CompressorDialog::OnSize )
   EVT_SLIDER( ThresholdID, CompressorDialog::OnSlider )
   EVT_SLIDER( RatioID, CompressorDialog::OnSlider )
   EVT_SLIDER( AttackID, CompressorDialog::OnSlider )
END_EVENT_TABLE()

CompressorDialog::CompressorDialog(EffectCompressor *effect,
                                   wxWindow *parent, wxWindowID id,
                                   const wxString &title,
                                   const wxPoint &position, const wxSize& size,
                                   long style ) :
   wxDialog( parent, id, title, position, size, style ),
   mEffect(effect)
{
   wxBoxSizer *mainSizer = new wxBoxSizer(wxVERTICAL);

   mainSizer->Add(new wxStaticText(this, -1,
                                   _("Dynamic Range Compressor by Dominic Mazzoni"),
                                   wxDefaultPosition, wxDefaultSize, wxALIGN_CENTRE),
                  0, wxALIGN_CENTRE|wxALL, 5);

   mPanel = new CompressorPanel(this, -1);
   mPanel->threshold = threshold;
   mPanel->ratio = ratio;
   mainSizer->Add(mPanel, 1, wxGROW|wxALIGN_CENTRE|wxALL, 5);

   wxFlexGridSizer *gridSizer = new wxFlexGridSizer(2, 0, 0);

   mThresholdText = new wxStaticText(this, -1, wxString(_("Threshold: ")) + wxT("XXX dB"));
   gridSizer->Add(mThresholdText, 0, wxALIGN_LEFT|wxALL, 5);

   mThresholdSlider = new wxSlider(this, ThresholdID, -8, -60, -1,
                                   wxDefaultPosition, wxSize(200, -1), wxSL_HORIZONTAL);
   gridSizer->Add(mThresholdSlider, 1, wxEXPAND|wxALL, 5);

   mRatioText = new wxStaticText(this, -1, wxString(_("Ratio: ")) + wxT("XXXX:1"));
   gridSizer->Add(mRatioText, 0, wxALIGN_LEFT|wxALL, 5);

   mRatioSlider = new wxSlider(this, RatioID, 4, 3, 20,
                               wxDefaultPosition, wxSize(200, -1), wxSL_HORIZONTAL);
   gridSizer->Add(mRatioSlider, 1, wxEXPAND|wxALL, 5);

   mAttackText = new wxStaticText(this, -1, wxString(_("Attack Time: ")) + wxT("XXXX secs"));
   gridSizer->Add(mAttackText, 0, wxALIGN_LEFT|wxALL, 5);

   mAttackSlider = new wxSlider(this, AttackID, 2, 1, 10,
                                wxDefaultPosition, wxSize(200, -1), wxSL_HORIZONTAL);
   gridSizer->Add(mAttackSlider, 1, wxEXPAND|wxALL, 5);

   mainSizer->Add(gridSizer, 0, wxALIGN_CENTRE|wxALIGN_CENTER_VERTICAL|wxALL, 5);

   wxBoxSizer *hSizer = new wxBoxSizer(wxHORIZONTAL);

   mGainCheckBox = new wxCheckBox(this, -1, _("Normalize to 0dB after compressing"));
   mGainCheckBox->SetValue(true);
   hSizer->Add(mGainCheckBox, 0, wxALIGN_LEFT|wxALL, 5);

   mainSizer->Add(hSizer, 0, wxALIGN_CENTRE|wxALIGN_CENTER_VERTICAL|wxALL, 5);

   hSizer = new wxBoxSizer(wxHORIZONTAL);

   wxButton *preview = new wxButton(this, PreviewID, mEffect->GetPreviewName());
   hSizer->Add(preview, 0, wxALIGN_CENTRE|wxALL, 5);
   hSizer->Add(40, 10);

   wxButton *cancel = new wxButton(this, wxID_CANCEL, _("Cancel"));
   hSizer->Add(cancel, 0, wxALIGN_CENTRE|wxALL, 5);

   wxButton *ok = new wxButton(this, wxID_OK, _("OK"));
   ok->SetDefault();
   ok->SetFocus();
   hSizer->Add(ok, 0, wxALIGN_CENTRE|wxALL, 5);

   mainSizer->Add(hSizer, 0, wxALIGN_CENTRE|wxALIGN_CENTER_VERTICAL|wxALL, 5);

   SetAutoLayout(true);
   SetSizer(mainSizer);
   mainSizer->Fit(this);
   mainSizer->SetSizeHints(this);

   SetSizeHints(500, 300, 20000, 20000);
   SetSize(500, 400);
}

bool CompressorDialog::TransferDataToWindow()
{
   mPanel->threshold = threshold;
   mPanel->ratio = ratio;

   mThresholdSlider->SetValue((int)rint(threshold));
   mRatioSlider->SetValue((int)rint(ratio*2));
   mAttackSlider->SetValue((int)rint(attack*10));
   mGainCheckBox->SetValue(useGain);

   TransferDataFromWindow();

   return true;
}

bool CompressorDialog::TransferDataFromWindow()
{
   threshold = (double)mThresholdSlider->GetValue();
   ratio = (double)(mRatioSlider->GetValue() / 2.0);
   attack = (double)(mAttackSlider->GetValue() / 10.0);
   useGain = mGainCheckBox->GetValue();

   mPanel->threshold = threshold;
   mPanel->ratio = ratio;

   mThresholdText->SetLabel(wxString::Format(_("Threshold: %d dB"), (int)threshold));

   if (mRatioSlider->GetValue()%2 == 0)
      mRatioText->SetLabel(wxString::Format(_("Ratio: %.0f:1"), ratio));
   else
      mRatioText->SetLabel(wxString::Format(_("Ratio: %.1f:1"), ratio));

   mAttackText->SetLabel(wxString::Format(_("Attack Time: %.1f secs"), attack));

   mPanel->Refresh(false);

   return true;
}

void CompressorDialog::OnSize(wxSizeEvent &event)
{
   event.Skip();
}

void CompressorDialog::OnOk(wxCommandEvent &event)
{
   TransferDataFromWindow();

   EndModal(true);
}

void CompressorDialog::OnPreview(wxCommandEvent &event)
{
   TransferDataFromWindow();

	// Save & restore parameters around Preview, because we didn't do OK.
   double    oldAttackTime = mEffect->mAttackTime;
   double    oldThresholdDB = mEffect->mThresholdDB;
   double    oldRatio = mEffect->mRatio;
   bool      oldUseGain = mEffect->mNormalize;

   mEffect->mAttackTime = attack;
   mEffect->mThresholdDB = threshold;
   mEffect->mRatio = ratio;
   mEffect->mNormalize = useGain;

   mEffect->Preview();

   mEffect->mAttackTime = oldAttackTime;
   mEffect->mThresholdDB = oldThresholdDB;
   mEffect->mRatio = oldRatio;
   mEffect->mNormalize = oldUseGain;
}

void CompressorDialog::OnCancel(wxCommandEvent &event)
{
   EndModal(false);
}

void CompressorDialog::OnSlider(wxCommandEvent &event)
{
   TransferDataFromWindow();
}