Solar Animation

{Written by Justin Wright November 2011}
{Include this text in a menu command. Set up the view and it will output a render file of sun animation}
{This is free for all to use}
{This is in a prelimnary state. USE AT OWN RISK!}

PROCEDURE RenderSunAnimation;
VAR
    iCount:INTEGER;
    iCount2:INTEGER;
    iReal:REAL;
    iQT:INTEGER;
    QTLongInt:LONGint;
    FileName:STRING;
    hHelidon:HANDLE;
    hLight:HANDLE;
    RenderLength:REAL;
    SunPos:REAL;
    Flip:INTEGER;
    RenderStart:INTEGER;
    RenderEnd:INTEGER;
    x1,y1:REAL;
    rNoNeed:REAL;
    rSunBright:REAL;
    bNoNeed:BOOLEAN;
    gLongitude,gLatitude:REAL;

{SunPossition: I got this formular from the internet. It is not perfect but very close}
FUNCTION SunPossition(DayNumber:REAL;Hour:REAL;Latitude:REAL;Longitude:REAL):HANDLE;

VAR
    FractionalYear:REAL;
    Declination:REAL;
    TimeCorrection:REAL;
    SolarHourAngle:REAL;
    SunAzimuthAngle:REAL;
    SunZenithAngle:REAL;
    SunElevationAngle:REAL;

BEGIN;

    Latitude:=Deg2Rad(Latitude);
    Longitude:=Deg2Rad(Longitude);
    FractionalYear:=(360/365.25)*(DayNumber + Hour/24);
        FractionalYear:=Deg2Rad(FractionalYear);


    Declination:=0.396372-22.91327*cos(FractionalYear)+4.02543*sin(FractionalYear)-0.387205*cos(2*FractionalYear)+0.051967*sin(2*FractionalYear)-0.154527*cos(3*FractionalYear) + 0.084798*sin(3*FractionalYear);
    TimeCorrection:=0.004297+0.107029*cos(FractionalYear)-1.837877*sin(FractionalYear)-0.837378*cos(2*FractionalYear)-2.340475*sin(2*FractionalYear);
    SolarHourAngle:=(Hour-12)*15 + Rad2Deg(Longitude) + TimeCorrection;

    IF SolarHourAngle>180 Then SolarHourAngle:=SolarHourAngle-360;
    IF SolarHourAngle<-180 Then SolarHourAngle:=SolarHourAngle+360;

    SolarHourAngle:=Deg2Rad(SolarHourAngle);
    Declination:=Deg2Rad(Declination);

    SunZenithAngle:=(sin(Latitude)*sin(Declination))+(cos(Latitude)*cos(Declination)*cos(SolarHourAngle));
    SunZenithAngle:=Rad2Deg(ArcCos(SunZenithAngle));


    SunElevationAngle:=90-SunZenithAngle;


    SunAzimuthAngle:=(sin(Declination)-sin(Latitude)*cos(Deg2Rad(SunZenithAngle)))/(cos(Latitude)*sin(Deg2Rad(SunZenithAngle)));
    SunAzimuthAngle:=Rad2Deg(ArcCos(SunAzimuthAngle));
    SunAzimuthAngle:=SunAzimuthAngle;

    IF -SunElevationAngle > 0 THEN
        BEGIN;
            IF SolarHourAngle>0 THEN SunAzimuthAngle:=360-SunAzimuthAngle;
            hLight:=CreateLight(0,0,0,0,True,True);
            SetLightDirection(hLight,-SunAzimuthAngle,-SunElevationAngle);
            HRotate(hLight,0,0,GetSymRot(GetObject('TheNorth')));
            SunPossition:=hLight;
        END;
END;


PROCEDURE AnimateSun;

BEGIN;
{This first cycle is for Summer equanox}
                For iCount:= RenderStart to REnderEnd DO
                            BEGIN
                            iReal:=iCount/RenderLength;
                            hLight:=SunPossition(355,iReal,gLongitude,gLatitude);
                                IF hLight<>NIL THEN
                                    BEGIN;
                                        ReDraw;
                                        QTWriteFrame(QTLongInt);
                                        DelObject(hLight);
                                        Message('Rendering Frame:',iCount);
                                    END;
                            END;
{This second cycle is for Summer equanox}
                For iCount:= RenderStart to REnderEnd DO
                            BEGIN
                            iReal:=iCount/RenderLength;
                            hLight:=SunPossition(355/2,iReal,gLongitude,gLatitude);
                            IF hLight<>NIL THEN
                                    BEGIN;
                                        ReDraw;
                                        QTWriteFrame(QTLongInt);
                                        DelObject(hLight);
                                        Message('Rendering Frame:',iCount);
                                    END;
                            END;
END;


{AnimateLightUp is not being used. It will fade in a light}
PROCEDURE AnimateLightUp;
Function LightUp(hLight:HANDLE):HANDLE;
VAR
iType:INTEGER;
rBright:INTEGER;

BEGIN;
GetLightInfo(hLight,iType,rBright,bNoNeed,bNoNeed);
SetLightInfo(hLight,iType,rBright+5,TRUE,TRUE);
LightUp:=hLight;
END;

BEGIN;
                SetLightInfo(GetObject('TheSun'),0,0,TRUE,TRUE);
                hLight:=GetObject('TheSun');
                For iCount:=1 to 20 Do
                    Begin;
                    SetText(GetObject('TheTitle'),Concat((5*iCount)) );
                    hLight:=LightUp(hLight);
                    ReDraw;
                    QTWriteFrame(QTLongInt);
                    Message('LightUp Frame:',icount);
                    End;
END;

BEGIN;
gLatitude:=-36.25;
gLongitude:=175;

GetLightInfo(GetObject('TheSun'),rNoNeed,rSunBright,bNoNeed,bNoNeed);
SetLightInfo(GetObject('TheSun'),0,rSunBright,FALSE,FALSE);

{You need to place Text object in the drawings. This will allow you to name the animation}
SetText(GetObject('TheTitle'),StrDialog('Title',''));

{Place a VW 'North Arrow' In the drawing and name it 'TheNorth'. This next part will get the rotation of your 'TheNorth' Object}
{The north will rotate the light object 'TheSun'}

IF GetObject('TheNorth') <> NIL
    THEN
        BEGIN;
            RenderLength:=RealDialog('Length of Animation in secounds','1');
            RenderStart:=7*RenderLength;
            REnderEnd:=18*RenderLength;
            iQT:=QTInitialize;
            QTLongInt:=QTOpenMovieFile(StrDialog('NameMovie',''));
            QTSetMovieOptions(QTLongInt,24,100,True,True);

            AnimateSun;

            QTCloseMovieFile(QTLongInt);
            QTTerminate;
            Message('Done');
        END
    ELSE
    BEGIN;
        AlrtDialog('You Need to Place a North Arrow and Name it TheNorth. Place it now');
        GetPT(x1,y1);
        SetName(CreateCustomObjectN('North Arrow',x1,y1,0,FALSE),'TheNorth');
        AlrtDialog('Next, now rotate it to face north so I can work out where the sun will come from, and run the script again');
    END;

SetLightInfo(GetObject('TheSun'),0,rSunBright,TRUE,TRUE);
END;
RUN(RenderSunAnimation);