//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include <math.h>
#include "PACSDK.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

const int ROTARY_SWITH_UNIT = 400;
const int ARROW_UNIT = 120;
const int CIRCLE_UNIT = 150;
const int NUMBER_UNIT = 175;
const int ORIGIN_X = ROTARY_SWITH_UNIT / 2;
const int ORIGIN_Y = ROTARY_SWITH_UNIT / 2;

//arrowPoints = vertices of the arrow shape
double arrowPointsX[] = {1, 0, 0, -1, -1, 0, 0};
double arrowPointsY[] = {0, -1, -0.5, -0.5, 0.5, 0.5, 1};
const int ARROW_POINT_NUM = 7;

TLabel * lbNumbers[10];  //numbers of the rotary switch

int CurrentRotaryID = -1;
int previousRotaryID = -1;  //used to prevent flash


//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
        double angle;
        int x, y;



        for (int i = 0; i < 10; i++)
        {
                angle = M_PI * 2 / 10 * i;

                //labels of number initialization
                lbNumbers[i] = new TLabel(this);
                x = (int)(cos(angle) * NUMBER_UNIT + ORIGIN_X);
                y = (int)(sin(angle) * NUMBER_UNIT + ORIGIN_Y);
                lbNumbers[i]->Left = x;
                lbNumbers[i]->Top = y;
                lbNumbers[i]->Caption = IntToStr(i);
                lbNumbers[i]->Font->Size = 16;
                lbNumbers[i]->Font->Style << fsBold;
                lbNumbers[i]->Font->Color = clWhite;
                lbNumbers[i]->Color = clBlack;
                lbNumbers[i]->Width = 20;
                lbNumbers[i]->Height = 20;
                lbNumbers[i]->Parent = Form1;
        }
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
        previousRotaryID = CurrentRotaryID;
        CurrentRotaryID = pac_GetRotaryID();

        if(CurrentRotaryID != previousRotaryID)  //to prevent flash
                RotaryPaint();
}
//---------------------------------------------------------------------------
DynamicArray<double> rotate(double x[], double y[], int length, int graduation)
{
        //vector rotation formula:
        // x2 = x1 * cos - y1 * sin
        //y2 = y1 * cos + x1 * sin

        double angle = M_PI * 2 / 10 * graduation;
        DynamicArray<double> dbArray;
        dbArray.Length = length * 2;

        for(int i=0;i<length; i++)
        {
                dbArray[2 * i] = x[i] * cos(angle) - y[i] * sin(angle);
                dbArray[2 * i + 1] = y[i] * cos(angle) + x[i] * sin(angle);
        }
        return dbArray;
}

//---------------------------------------------------------------------------
void CalculateArrowPoints(int graduation, TPoint * rotatedArrow)
{
        DynamicArray<double> rotatedArrowPoints;
        rotatedArrowPoints.Length = ARROW_POINT_NUM * 2;

        int x, y;

        rotatedArrowPoints = rotate(arrowPointsX, arrowPointsY, ARROW_POINT_NUM, graduation);
        for (int i = 0; i < ARROW_POINT_NUM; i++)
        {
                TPoint pt;
                x = (int)(ARROW_UNIT * rotatedArrowPoints[2 * i] + ORIGIN_X);
                y = (int)(ARROW_UNIT * rotatedArrowPoints[2 * i + 1] + ORIGIN_Y);
                pt.x = x;
                pt.y = y;
                rotatedArrow[i] = pt;
        }

}

//---------------------------------------------------------------------------
void __fastcall TForm1::RotaryPaint()
{
        TPoint arrowPt[ARROW_POINT_NUM];

        Form1->Canvas->Brush->Color = clWhite;
        Form1->Canvas->Ellipse(ORIGIN_X - CIRCLE_UNIT,
                        ORIGIN_Y - CIRCLE_UNIT,
                        ORIGIN_X - CIRCLE_UNIT + CIRCLE_UNIT * 2,
                        ORIGIN_Y - CIRCLE_UNIT + CIRCLE_UNIT * 2
                        );

        CalculateArrowPoints(CurrentRotaryID, arrowPt);
        arrowPt[ARROW_POINT_NUM] = arrowPt[0];   //eight points with 8th = first

        Form1->Canvas->Brush->Color = clGray;
        Form1->Canvas->Polygon(arrowPt, ARROW_POINT_NUM);

}
//---------------------------------------------------------------------------