//===========================================================================
//                                      VISUALIZING AND SONIFYING A SINE WAVE
//                                               N. Gessler 13 September 2015
//===========================================================================

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include <mmsystem.h>                                         // enables MIDI

//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

//===========================================================================
//                                                                  VARIABLES
//===========================================================================

float x, y;

// for the MIDI device

int midiport = 0;
HMIDIOUT device;

union {
   public:
   unsigned long word;
   unsigned char data[4];
} message;

int instrument = 10;  // "marimba" but sounds like 13 xylophone
int note;

int whole = 500;

//===========================================================================
//                                                                  FUNCTIONS
//===========================================================================

//--------------------------------------------------- Color Ramp Version 2012
TColor colorRamp(int part, int whole)
{
	if (whole == 0) whole = 1;             // prevent divide by zero
	part = part % whole;                   // keep part <= whole
	int pixelDistanceAlongEdges = (part * 1792) / whole;
	int red, green, blue;
	// Which edge of the color cube are we on?
	if (pixelDistanceAlongEdges < 256) {        // from BLACK to BLUE
		red = 0; green = 0; blue = pixelDistanceAlongEdges;
	}
	else if (pixelDistanceAlongEdges < 512) {   // from BLUE to CYAN
		red = 0; green = pixelDistanceAlongEdges - 256; blue = 255;
	}
	else if (pixelDistanceAlongEdges < 768) {   // from CYAN to GREEN
		red = 0; green = 255; blue = 255 - (pixelDistanceAlongEdges - 512);
	}
	else if (pixelDistanceAlongEdges < 1024) {  // from GREEN to YELLOW
		red = (pixelDistanceAlongEdges - 768); green = 255; blue = 0;
	}
	else if (pixelDistanceAlongEdges < 1280) {  // from YELLOW to RED
		red = 255; green= 255-(pixelDistanceAlongEdges - 1024); blue = 0;
	}
	else if (pixelDistanceAlongEdges < 1536) {  // from RED to MAGENTA
		red = 255; green= 0; blue = pixelDistanceAlongEdges - 1280;
	}
	else {                                     // from MAGENTA to WHITE
		red = 255; green = pixelDistanceAlongEdges - 1537; blue = 255;
	}
	return static_cast<TColor>(RGB(red, green, blue));
}

//------------------------------------------------------- 2012.01.21 midiRamp
// Be aware that the range of notes is different for different instruments.
// This code does not take that into account.
int midiRamp(int part, int whole) {
	// only using the 47 MIDI notes which range from 35 to 81
		if (whole == 0) whole = 1;     // prevent divide by zero
		part = part % whole;           // keep part less than whole
	note = (part * 47) / whole;
	note = note + 35;
	return note;
}

void drawBox (void) {
	Form1->PaintBox1->Canvas->MoveTo(0, 0);
	Form1->PaintBox1->Canvas->LineTo(Form1->PaintBox1->Width - 1, 0);
	Form1->PaintBox1->Canvas->LineTo(Form1->PaintBox1->Width - 1, Form1->PaintBox1->Height - 1);
	Form1->PaintBox1->Canvas->LineTo(0, Form1->PaintBox1->Height - 1);
	Form1->PaintBox1->Canvas->LineTo(0, 0);
}

// Creates a sine wave 500 pixels high beginning at 0
void sineWave (void) {
	Form1->PaintBox1->Refresh();
	Form1->PaintBox1->Canvas->Pen->Width = 4;
	Form1->PaintBox1->Canvas->Pen->Color = clRed;
	Form1->PaintBox1->Canvas->Brush->Color = clGray;
	Form1->PaintBox1->Canvas->Rectangle(0, 0, 660, 500);
	//drawBox();

	Form1->PaintBox1->Canvas->Pen->Width = 1;
	Form1->PaintBox1->Canvas->Pen->Color = clBlack;
	Form1->PaintBox1->Canvas->MoveTo(800, 500);
	Form1->PaintBox1->Canvas->LineTo(0, 500);
	for (x = M_PI / 2; x <= 2. * M_PI + M_PI / 2; x+=.05) {
		y = 250 + 250 * sin(x);

		Sleep(60);                   // interval between notes & colors

		// select the viusualization color and draw an ellipse
		Form1->PaintBox1->Canvas->Pen->Color = colorRamp(y, whole);
		Form1->PaintBox1->Canvas->Brush->Color = colorRamp(500 - y, whole);
		Form1->PaintBox1->Canvas->Ellipse(x * 100 - 150, y, x * 100 - 150 + 20, y + 20);

        // select a sonification note and play it
		//if (y == 0) continue;                	// if we want 0 to be silent
		note = midiRamp(500 - y, whole);          // the call
		message.data[0] = 0x90;                 // note on
		message.data[1] = note;                 // note #
		midiOutShortMsg(device, message.word);  // do it

		Form1->EditX->Text = (x * 100 - 150);
		Form1->EditY->Text = (500 - y);

		Application->ProcessMessages();

	}


}

//===========================================================================
//                                                             EVENT HANDLERS
//===========================================================================

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
	: TForm(Owner)
{
   DoubleBuffered = true;   // corrects display glitches

   // set up midi device
   midiOutOpen(&device, midiport, 0, 0, CALLBACK_NULL);
   message.data[0] = 0xC0;         // choose instrument command
   message.data[1] = instrument;   // instrument
   message.data[2] = 100;          // once set, no need to repeat
   message.data[3] = 0;            // once set, no need to repeat
   midiOutShortMsg(device, message.word);
}

//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonRunClick(TObject *Sender)
{
	sineWave();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::TrackBarWholeChange(TObject *Sender)
{
	whole = TrackBarWhole->Position;
	Form1->EditWhole->Text = whole;
}
//---------------------------------------------------------------------------

void __fastcall TForm1::EditWholeChange(TObject *Sender)
{
	Form1->TrackBarWhole->Position = StrToInt(EditWhole->Text);
}
//---------------------------------------------------------------------------