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Re: My flaky math

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Den måndag 9 december 2019 kl. 09:59:51 UTC+1 skrev Jonas Thörnvall:
> Den måndag 9 december 2019 kl. 09:51:42 UTC+1 skrev Jonas Thörnvall:
> > Den lördag 7 december 2019 kl. 19:44:08 UTC+1 skrev Jonas Thörnvall:
> > > When i move selection to middle and then move the start point the selection start to drift within timeframe, should i calcMarking another way?
> > > 
> > > There must be a logical error because as i see it left and right are percentages of the total time that is the length of the bar so i do not think i move it relative a static target just timespann. And the marking shrink and expand with the timetotal, but it drifts? "When you change startpoint relative the marking".
> > > 
> > > https://midisequenser.000webhostapp.com/
> > > 
> > > function calcMarking(){
> > > 	//Do calculation
> > > 	var LeftTime=parseInt(document.getElementById("recstart").value);
> > > 	var RightTime=parseInt(document.getElementById("recend").value);
> > > 	var TimeSPos=document.getElementById("EditStart").value;
> > > 	var TimeEPos=document.getElementById("EditEnd").value;
> > > 	var distanceTotal=Mwidth-50;
> > > 	var TimeTotal=TimeEPos-TimeSPos;
> > > 	console.log("TimeEPos="+TimeEPos+" TimeSPos="+TimeSPos+" Timetotal="+TimeTotal);
> > > 	var RightPercent=RightTime/TimeTotal;
> > > 	var LeftPercent=LeftTime/TimeTotal;
> > > 	zz=50+(RightPercent*distanceTotal);
> > > 	yy=50+(LeftPercent*distanceTotal);
> > > }
> > > 
> > > 
> > > // This below is just the drawout and i don't think it is anything there
> > > // I think there is flaky math or flaky logic above.
> > > // It has no real importance for the functionality, but should look nice i guess
> > > 
> > > function drawMarked() {
> > > var LeftTime=parseInt(document.getElementById("recstart").value);
> > > var RightTime=parseInt(document.getElementById("recend").value);	
> > > var TimeSPos=document.getElementById("EditStart").value;
> > > var TimeEPos=document.getElementById("EditEnd").value;
> > > if(LeftTime>=TimeSPos && RightTime<=TimeEPos && mode=="Listen")  {
> > > 	calcMarking();
> > > 	drawOutMark();
> > > 	leftMarker();
> > > 	rightMarker();
> > >  }  
> > > }
> > > 
> > > 
> > > 
> > > function drawOutMark(){
> > > 	ctm.fillStyle ="#661313";
> > > 	ctm.fillRect(yy, 25,zz-yy,Mheight);
> > > }
> > > 
> > > function leftMarker(){
> > >     ctm.fillStyle = "orange";
> > >     ctm.beginPath();
> > >     ctm.moveTo(yy-10, 15);
> > >     ctm.lineTo(yy+10, 15);
> > >     ctm.lineTo(yy, 25);
> > >     ctm.fill();
> > > }
> > > 
> > > function rightMarker(){
> > >     ctm.fillStyle = "orange";
> > >     ctm.beginPath();
> > >     ctm.moveTo(zz-10, 15);
> > >     ctm.lineTo(zz+10, 15);
> > >     ctm.lineTo(zz, 25);
> > > 	ctm.lineWidth = 2;
> > >     ctm.fill();
> > > }
> > 
> > I think the correct math involve transforming right and left "selected markers" into fractions relative the length of FRACTION=(righttime-lefttime)/totaltime
> > And then newleftime=leftime*FRACTION and newrighttime=rightime*fraction.
> > 
> > And then take the fraction of Rightperc=newrighttime/totaltime
> > And then Rightperc*totaltime
> > 
> > But i am not in the mood to fiddle with it.
> > There is other things to fix like the trackeditor.
> > 
> > I would say it work now, for the use intended "yeah i can see it drift a little" when the startbar run high.
> 
> At bar 450 or so it have drifted a full bar...

Well now i think you will find the accuracy good enough for some hundred million of bars, but what is the math really?

function calcMarking(){
	var STARTBAR=document.getElementById("SB").value;
	var LeftTime=parseInt(document.getElementById("recstart").value);
	var RightTime=parseInt(document.getElementById("recend").value);	
	var TimeSPos=document.getElementById("EditStart").value;
	var TimeEPos=document.getElementById("EditEnd").value;
	//Do calculation
	distanceTotal=Mwidth-50;
	TimeTotal=TimeEPos-TimeSPos;
	RightPerc=RightTime/TimeTotal;
	LeftPerc=LeftTime/TimeTotal;
	zz=50+(RightPerc*distanceTotal)-(barlength*STARTBAR)*0.99771462;
	yy=50+(LeftPerc*distanceTotal)-(barlength*STARTBAR)*0.99771462;
}

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My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-07 10:44 -0800
  Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-07 11:24 -0800
  Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-07 11:43 -0800
    Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 00:26 -0800
      Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 00:33 -0800
        Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 00:35 -0800
  Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 00:51 -0800
    Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 00:59 -0800
      Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 03:03 -0800
        Re: My flaky math Jonas Thörnvall <jonas.thornvall@gmail.com> - 2019-12-09 04:12 -0800

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