3rd screenshot mentioned in the post above, please.

No it is not. However, it is appearing so. As previously mentioned by @PanoS, It is happening because of anisotropic property of charts.

Anyways, below is a code, where it is mathematically proven that ABCD is a square and hence by default it implies that the quadrilateral PQRS formed out of the mid-points of its sides is also a square.

```
function RadToDeg( x ) {
pi = atan( 1 ) * 4;
return x * ( 180 / pi ); //Angle is calculated in radians, thus converting it to degrees
}
_SECTION_BEGIN( "Square off a Trendline" );
SetChartOptions( 1, chartShowDates );
bi = BarIndex();
ChartId = Name() + GetChartId();
//////////////////////////////////////////////////////////////
///////////// Capturing co-ordinates of A and B //////////////
//////////////////////////////////////////////////////////////
LeftMsBtnJustClkd = GetCursorMouseButtons() & 8;
LeftMsBtnDownRlsd = GetCursorMouseButtons() & 9;
MsMiddleBtnClkd = GetCursorMouseButtons() & 4;
x = GetCursorXPosition( 0 );
y = GetCursorYPosition( 0 );
CtrlPressed = GetAsyncKeyState( 17 ) < 0;
if( CtrlPressed ) {
if( LeftMsBtnJustClkd ) {
StaticVarSet( "Ax" + ChartId, x, 0 );
StaticVarSet( "Ay" + ChartId, y, 0 );
}
if( LeftMsBtnDownRlsd ) {
StaticVarSet( "Bx" + ChartId, x, 0 );
StaticVarSet( "By" + ChartId, y, 0 );
}
if( MsMiddleBtnClkd ) {
StaticVarRemove( "Ax" + ChartId );
StaticVarRemove( "Ay" + ChartId );
StaticVarRemove( "Bx" + ChartId );
StaticVarRemove( "By" + ChartId );
}
RequestMouseMoveRefresh();
}
//////////////////////////////////////////////////////////////
GfxSetZOrder( 0 );
GfxSetCoordsMode( 1 );
GfxSetBkMode( 1 );
GfxSelectFont( "Arial", 8, 400 );
GfxSetTextColor( colorLavender );
GfxSelectPen( colorBlueGrey, 1, 0 );
_Ax = Lookup( bi, StaticVarGet( "Ax" + ChartId ) );
_Ay = StaticVarGet( "Ay" + ChartId );
_Bx = Lookup( bi, StaticVarGet( "Bx" + ChartId ) );
_By = StaticVarGet( "By" + ChartId );
if( _Ax != 0 AND _Bx != 0 ) {
// Using GFX, drawing a line between A and B
GfxMoveTo( _Ax, _Ay );
GfxLineTo( _Bx, _By );
// Finding co-ordinates of C and D (ABCD being a square)
dX = _Bx - _Ax; dY = _By - _Ay;
_Cx = _Bx + dY ; _Cy = _By - dx ;
_Dx = _Ax + dY ; _Dy = _Ay - dx ;
// Drawing a line between B and C
GfxMoveTo( _Bx, _By );
GfxLineTo( _Cx, _Cy );
// Drawing a line between A and D
GfxMoveTo( _Ax, _Ay );
GfxLineTo( _Dx, _Dy );
// Drawing a line between C and D
GfxMoveTo( _Cx, _Cy );
GfxLineTo( _Dx, _Dy );
// Drawing diagonals of the square ABCD
GfxMoveTo( _Ax, _Ay );
GfxLineTo( _Cx, _Cy );
GfxMoveTo( _Bx, _By );
GfxLineTo( _Dx, _Dy );
// Finding mid-points of the sides of ABCD
Px = ( _Ax + _Bx ) / 2; Py = ( _Ay + _By ) / 2;
Qx = ( _Bx + _Cx ) / 2; Qy = ( _By + _Cy ) / 2;
Rx = ( _Cx + _Dx ) / 2; Ry = ( _Cy + _Dy ) / 2;
Sx = ( _Ax + _Dx ) / 2; Sy = ( _Ay + _Dy ) / 2;
// Drawing a square PQRS
GfxMoveTo( Px, Py ); GfxLineTo( Qx, Qy );
GfxMoveTo( Qx, Qy ); GfxLineTo( Rx, Ry );
GfxMoveTo( Rx, Ry ); GfxLineTo( Sx, Sy );
GfxMoveTo( Sx, Sy ); GfxLineTo( Px, Py );
// Text for co-ordinates
GfxTextOut( "A", _Ax, _Ay );
GfxTextOut( "B", _Bx, _By );
GfxTextOut( "C", _Cx, _Cy );
GfxTextOut( "D", _Dx, _Dy );
GfxTextOut( "P", Px, Py );
GfxTextOut( "Q", Qx, Qy );
GfxTextOut( "R", Rx, Ry );
GfxTextOut( "S", Sx, Sy );
//////////////////////////////////////////////////////////////
/////////////// Proving that ABCD is a square ////////////////
//////////////////////////////////////////////////////////////
// Measuring length of the sides using Distance formula
AB = sqrt( dX ^ 2 + dY ^ 2 );
BC = sqrt( ( _Cx - _Bx ) ^ 2 + ( _Cy - _By ) ^ 2 );
CD = sqrt( ( _Dx - _Cx ) ^ 2 + ( _Dy - _Cy ) ^ 2 );
DA = sqrt( ( _Dx - _Ax ) ^ 2 + ( _Dy - _Ay ) ^ 2 );
// Finding angle of the vertices of ABCD
CAD = atan( CD / DA ); CAB = atan( BC / AB ); /*Hence,*/ DAB = RadToDeg( CAD + CAB );
DBA = atan( DA / AB ); DBC = atan( CD / BC ); /*Hence,*/ ABC = RadToDeg( DBA + DBC );
ACB = atan( AB / BC ); ACD = atan( DA / CD ); /*Hence,*/ BCD = RadToDeg( ACB + ACD );
BDC = atan( BC / CD ); BDA = atan( AB / DA ); /*Hence,*/ CDA = RadToDeg( BDC + BDA );
Title =
"Proof 1: All sides of ABCD are equal" +
StrFormat( "\nAB = %1.2f, BC = %1.2f, CD = %1.2f, DA = %1.2f", AB, BC, CD, DA ) +
"\nAB = BC = CD = DA = " + WriteIf( AB == BC && BC == CD && CD == DA, "True", "False" ) +
"\n\nProof 2: All vertices of ABCD are of 90°" +
StrFormat( "\nDAB = %1.0f°, ABC = %1.0f°, BCD = %1.0f°, CDA = %1.0f°", DAB, ABC, BCD, CDA ) +
"\nAngle A = B = C = D = " + WriteIf( DAB == ABC && ABC == BCD && BCD == CDA, "True", "False" )
;
//////////////////////////////////////////////////////////////
}
Plot( C, "Price", colorDefault, styleCandle );
_SECTION_END();
```

Hello Cougar,

Thank you for your help. I understood that part now. By using zoom - shorter bars & taller bars options, I am able to see the square shape on the chart.

Though, somehow I am not able to see Proof related text on the chart which I see on your screenshot on upper left part. If possible, let me know how to get it displayed on chart, please.

When selected point A has lower price & selected point B has higher price, it draws downward facing square on the right side of the selected points, which is awesome.

If possible, I would like to have square drawn to upward & right side of a trend line when a selected point A has higher price, selected point B has lower price & selected point B is located on (lower) right side from selected point A as shown in my screenshot below with this post, please. In other words, point A has occurred earlier (date/time) then point B (date/time)

In the GIF screenshot that you have displayed in your last reply, has point A has higher price & point B has lower price but Point B is located on (lower) left side from point A.

I am ok to use 2 separate indicators (one for each case) if its not possible to draw square using single indicator, please.

Thank you.

Use the latter code and draw a new trendline using CTRL & Mouse Left Button down. The moment you draw, the Title text will appear.

DIY please... You have all the cues in place!

Hint:

```
// Finding co-ordinates of C and D (ABCD being a square)
dX = _Bx - _Ax; dY = _By - _Ay;
_Cx = _Bx + dY ; _Cy = _By - dx ;
_Dx = _Ax + dY ; _Dy = _Ay - dx ;
```

Hello Cougar,

Thank you for your comments & Hint.

I will try to DIM (Do it myself) & apply those changes.

Thank you.

Do share your efforts!

Would be happy to help... It's just that one does not learn, if everything is showcased.

Thank you

Hello Cougar,

I agree. I will try to update. Once I get the desired result, I will share that code over here.

Thank you.

Very nice clean afl code with details, good job @Cougar

We can insert to your code (**after line 40**) the below code that is just for editing the point A or point B of the main line

I think now the @trader123 he have to hit the hart image button or solution on your post Cougar, as you spent at least one day just to help him.

```
//////////////////////////////////////////////////////////////
// For Editing TRENDLINE POINTS A OR B, (by holding keyboard button A OR B and just a Click Mouse Left Button )
//////////////////////////////////////////////////////////////
AlfaPressed = GetAsyncKeyState( 65 ) < 0;
BetaPressed = GetAsyncKeyState( 66 ) < 0;
if( AlfaPressed ) {
if( LeftMsBtnJustClkd ) {
StaticVarSet( "Ax" + ChartId, x, 0 );
StaticVarSet( "Ay" + ChartId, y, 0 );
} RequestMouseMoveRefresh();
}
if( BetaPressed) {
if( LeftMsBtnJustClkd ) {
StaticVarSet( "Bx" + ChartId, x, 0 );
StaticVarSet( "By" + ChartId, y, 0 );
} RequestMouseMoveRefresh();
}
//////////////////////////////////////////////////////////////
```

Thank you

Nah!... About an hour (occasionally distracted by other things)... I was not doing anything either, would have anyways wasted that time... Productive utilization of free time so to speak...

BTW, there is a simpler way to flip the squares just by toggling the sign of delta of axis coordinates (line 61 - 63).

```
// Finding co-ordinates of C and D (ABCD being a square)
dX = _Bx - _Ax; dY = _By - _Ay;
_Cx = _Bx + dY ; _Cy = _By - dx ;
_Dx = _Ax + dY ; _Dy = _Ay - dx ;
```

Flipping the squares by changing sign:

```
dX = _Bx - _Ax; dY = _By - _Ay;
_Cx = _Bx - dY ; _Cy = _By + dx ;
_Dx = _Ax - dY ; _Dy = _Ay + dx ;
```

Thank you Cougar & PanoS for your help.

Hello Cougar & PanoS,

I have got solution to draw the square on the chart. Various points of the chart can be used as support & resistance. Various side of the square can also be used as support & resistance. That's the usage of it, which you helped me with.

I had purchased Amibroker Professional Edition since early 2017 but was not using as much till now. Since, I got this interesting setup available on chart, I am planning to use it more often now. In that regards, I have one more query which I have posted it at following location in this forum, please.

If possible, I would like to request you to review it & let me know your input, please.

Thank you.

Hello Cougar,

When I draw square on S&P500 M5 & H1 charts. It works good. But when I draw square on S&P500 D1 (Daily) chart, side AD and BC stretch out a lot & square does not get completed within screen limit. As discussed earlier in the post, I think its due to difference in the unit of X-axis & Y-axis.

Similarly, when I try to draw square on EURUSD M5 chart & select point A & B then side AD & BC tend to extend to infinity. If you get chance, let me know if anything can be done for these situation, please.

You can re-solve that easily by converting Bar (on X-axis) and Price (on Y-axis) to pixel co-ordinates and then use `GfxSetCoordsMode`

set to `0`

(instead of `1`

as previously used). Try this:

```
// To convert from Bar (on X-axis) and Price (on Y-axis) to pixel co-ordinates
// Link: http://www.amibroker.com/kb/2009/03/30/how-to-convert-from-bar-value-to-pixel-co-ordinates/
Miny = Status( "axisminy" );
Maxy = Status( "axismaxy" );
lvb = Status( "lastvisiblebar" );
fvb = Status( "firstvisiblebar" );
pxchartleft = Status( "pxchartleft" );
pxchartwidth = Status( "pxchartwidth" );
pxchartbottom = Status( "pxchartbottom" );
pxchartheight = Status( "pxchartheight" );
function XtoPxX( bar ) { return pxchartleft + ( bar - fvb ) * pxchartwidth / ( lvb - fvb + 1 ); }
function YtoPxY( value ) { return pxchartbottom - floor( 0.5 + ( value - Miny ) * pxchartheight / ( Maxy - Miny + 1e-9 ) ); }
function RadToDeg( x ) {
pi = atan( 1 ) * 4;
return x * ( 180 / pi ); //Angle is calculated in radians, thus converting it to degrees
}
_SECTION_BEGIN( "Square off a Trendline" );
SetChartOptions( 1, chartShowDates );
bi = BarIndex();
ChartId = Name() + GetChartId();
//////////////////////////////////////////////////////////////
///////////// Capturing co-ordinates of A and B //////////////
//////////////////////////////////////////////////////////////
LeftMsBtnJustClkd = GetCursorMouseButtons() & 8;
LeftMsBtnDownRlsd = GetCursorMouseButtons() & 9;
MsMiddleBtnClkd = GetCursorMouseButtons() & 4;
x = GetCursorXPosition( 0 );
y = GetCursorYPosition( 0 );
CtrlPressed = GetAsyncKeyState( 17 ) < 0;
if( CtrlPressed ) {
if( LeftMsBtnJustClkd ) {
StaticVarSet( "Ax" + ChartId, x, 0, False );
StaticVarSet( "Ay" + ChartId, y, 0, False );
}
if( LeftMsBtnDownRlsd ) {
StaticVarSet( "Bx" + ChartId, x, 0, False );
StaticVarSet( "By" + ChartId, y, 0, False );
}
if( MsMiddleBtnClkd ) {
StaticVarRemove( "Ax" + ChartId );
StaticVarRemove( "Ay" + ChartId );
StaticVarRemove( "Bx" + ChartId );
StaticVarRemove( "By" + ChartId );
}
}
//////////////////////////////////////////////////////////////
GfxSetZOrder( 0 );
GfxSetCoordsMode( 0 );
GfxSetBkMode( 1 );
GfxSelectFont( "Arial", 8, 400 );
GfxSetTextColor( colorLavender );
GfxSelectPen( colorBlueGrey, 1, 0 );
_Ax = XtoPxX( Lookup( bi, StaticVarGet( "Ax" + ChartId ) ) );
_Ay = YtoPxY( StaticVarGet( "Ay" + ChartId ) );
_Bx = XtoPxX( Lookup( bi, StaticVarGet( "Bx" + ChartId ) ) );
_By = YtoPxY( StaticVarGet( "By" + ChartId ) );
if( _Ax > 0 && _Bx > 0 ) {
// Finding co-ordinates of C and D (ABCD being a square)
dX = _Bx - _Ax; dY = _By - _Ay;
_Cx = _Bx - dY; _Cy = _By + dx;
_Dx = _Ax - dY; _Dy = _Ay + dx;
// Drawing square ABCD
GfxMoveTo( _Ax, _Ay ); GfxLineTo( _Bx, _By );
GfxMoveTo( _Bx, _By ); GfxLineTo( _Cx, _Cy );
GfxMoveTo( _Ax, _Ay ); GfxLineTo( _Dx, _Dy );
GfxMoveTo( _Cx, _Cy ); GfxLineTo( _Dx, _Dy );
// Drawing diagonals of the square ABCD
GfxMoveTo( _Ax, _Ay ); GfxLineTo( _Cx, _Cy );
GfxMoveTo( _Bx, _By ); GfxLineTo( _Dx, _Dy );
// Finding mid-points of the sides of ABCD
Px = ( _Ax + _Bx ) / 2; Py = ( _Ay + _By ) / 2;
Qx = ( _Bx + _Cx ) / 2; Qy = ( _By + _Cy ) / 2;
Rx = ( _Cx + _Dx ) / 2; Ry = ( _Cy + _Dy ) / 2;
Sx = ( _Ax + _Dx ) / 2; Sy = ( _Ay + _Dy ) / 2;
// Drawing a square PQRS
GfxMoveTo( Px, Py ); GfxLineTo( Qx, Qy );
GfxMoveTo( Qx, Qy ); GfxLineTo( Rx, Ry );
GfxMoveTo( Rx, Ry ); GfxLineTo( Sx, Sy );
GfxMoveTo( Sx, Sy ); GfxLineTo( Px, Py );
// Text for co-ordinates
GfxTextOut( "A", _Ax, _Ay ); GfxTextOut( "B", _Bx, _By ); GfxTextOut( "C", _Cx, _Cy ); GfxTextOut( "D", _Dx, _Dy );
GfxTextOut( "P", Px, Py ); GfxTextOut( "Q", Qx, Qy ); GfxTextOut( "R", Rx, Ry ); GfxTextOut( "S", Sx, Sy );
//////////////////////////////////////////////////////////////
/////////////// Proving that ABCD is a square ////////////////
//////////////////////////////////////////////////////////////
// Measuring length of the sides using Distance formula (in pixels)
AB = sqrt( dX ^ 2 + dY ^ 2 );
BC = sqrt( ( _Cx - _Bx ) ^ 2 + ( _Cy - _By ) ^ 2 );
CD = sqrt( ( _Dx - _Cx ) ^ 2 + ( _Dy - _Cy ) ^ 2 );
DA = sqrt( ( _Dx - _Ax ) ^ 2 + ( _Dy - _Ay ) ^ 2 );
// Finding angle of the vertices of ABCD
CAD = atan( CD / DA ); CAB = atan( BC / AB ); /*Hence,*/ DAB = RadToDeg( CAD + CAB );
DBA = atan( DA / AB ); DBC = atan( CD / BC ); /*Hence,*/ ABC = RadToDeg( DBA + DBC );
ACB = atan( AB / BC ); ACD = atan( DA / CD ); /*Hence,*/ BCD = RadToDeg( ACB + ACD );
BDC = atan( BC / CD ); BDA = atan( AB / DA ); /*Hence,*/ CDA = RadToDeg( BDC + BDA );
Title =
"Proof 1: All sides of ABCD are equal (in pixels)" +
StrFormat( "\nAB = %1.2f, BC = %1.2f, CD = %1.2f, DA = %1.2f", AB, BC, CD, DA ) +
"\nAB = BC = CD = DA = " + WriteIf( AB == BC && BC == CD && CD == DA, "True", "False" ) +
"\n\nProof 2: All vertices of ABCD are of 90°" +
StrFormat( "\nDAB = %1.0f°, ABC = %1.0f°, BCD = %1.0f°, CDA = %1.0f°", DAB, ABC, BCD, CDA ) +
"\nAngle A = B = C = D = " + WriteIf( DAB == ABC && ABC == BCD && BCD == CDA, "True", "False" )
;
//////////////////////////////////////////////////////////////
}
Plot( C, "Price", colorDefault, styleCandle );
RequestMouseMoveRefresh();
_SECTION_END();
```

Yes!

And scaling as Tomasz wrote about it here. Quoting him:

Hello Cougar,

Thank you for taking time & providing updated code. I have tried it on different instruments & different time frames. I have tried drawing square on S&P500 - M5, H1 & D1 and EURUSD - M5, H1 & D1 charts. Its working good now.

Thank you.

Hello Trader123,

Why the update code is a backward draw when I choose Peak and Vallery. Can you show for the updated code? It is useful.

Hi,

I tried to draw circle around the square, have read help file etc, still I am unable to draw it properly.

```
GfxSelectStockObject( 5 );
Cirstar = (( _Ax + _Ay ) + ( _Cx + _Cy ))/2 ;
yAxisM = ( _Ax + _Ay );
r = sqrt(( _Bx + _By )^2 + ( _Dx + _Dy )^2);
GfxMoveTo(_Ax,_Ay);
GfxCircle ( Cirstar, yAxisM, r);
```

Made some progress, still unable to calculate proper radius. Image didn't got uploaded.

```
Cen1 = (_Ax + _Cx)/2 ; Cen2 = (_Ay + _Cy)/2 ;
rad = sqrt( (_Ax+_Cx) + (_Ay+_Cy)) +sqrt((_Bx+_Dx) +(_By+_DY)) ;
GfxSelectStockObject( 5 );
GfxCircle(Cen1,Cen2,rad);pe or paste code here
```

Looks like found solution.

```
Cen1 = (_Ax + _Cx)/2 ; Cen2 = (_Ay + _Cy)/2 ;
rad = sqrt( dX ^ 2 + dY ^ 2 )/2;
r = (sqrt( ( _Cx - _Bx ) ^ 2 + ( _Cy - _By ) ^ 2 ))/1.41;
GfxSelectStockObject( 5 );
GfxCircle(Cen1,Cen2,rad);
GfxCircle(Cen1, Cen2,r);
```

if someone wants Circle from trendline....

```
GfxCircle(Px,Py,rad);
```

Hi Cougar,

is there anyway can make the afl become explorable ;

- point A and B either top or valley for days range input in parameter
- filter exploring point C if valley is in A and Top is in B , vice versa for point D

i try to modif the code but not working at all.

Thank you