How do I draw multiple points from multiple lat longs pairs?

I'm not sure if I understood it correctly, but it's quite easy to draw a straight line connecting two points with Graphics.drawLine().

https://developer.garmin.com/connect-iq/api-docs/Toybox/Graphics/Dc.html#drawLine-instance_function

By saving the coordinates of the last point, you've the pair of points, i.e. lastPoint and actualPoint, which can be connected with drawLine() and so on.

I think we move away from your OP. The theme of your OP is "How do I draw multiple points from multiple lat longs pairs?" and afterwards you wanted

"Would you be willing to provide an example I can use instead to draw the points?"

Therefore I've coded a raw example how to may solve this with using drawCircle() which are drawing the points. If you'ld like to draw the connections between the points instead, then you've to use drawLine(), like e.g.

// set graphics rendering
dc.setColor(...);
dc.setPenWidth(...);

// using 1-dim array like 
// track[lat1,lon1,lat2,lon2,lat3,...}
for(i=0; i < (track.size() - 2), i+=2) {
    // calculate point locations in pixels
    var pixelsLon = (track[i+3] - track[i+1]) * scaleXY;
    var pixelsLat = (track[i+2] - track[i])   * scaleXY;

    // adjust point locations to a reference point
    var displayX = pixelsLon + pixelsXRef;
    var displayY = pixelsLat + pixelsYRef;

    // draw points
	dc.fillCircle(displayX, displayY, 2);
	
	// draw lines
	if (i == 0) {
	    var displayXOld = displayX;
	    var displayYOld = displayY;

	} else {
	    dc.drawLine(displayXOld, displayYOld, displayX, displayY);
	    displayXOld = displayX;
	    displayYOld = displayY;
    }	 
}
...

This is only an example that points out how you may solve this, especially it's not perfect code because it depends on the rest of the program.

Yes, Originally when I made thr post I should have included the drawing line functionality, I can see how it hs got a bit confusing, i’ll play around with the code you’ve provided later, thankyou.

if(lat != null){
var lonMax = -180.0;
var lonMin = 180.0;
var latMax = -90.0;
var latMin = 90.0;
for(var i=0; i < lat.size(); i++) {
lonMax = (lonMax > lon[i]) ? lonMax : lon[i];
lonMin = (lonMin < lon[i]) ? lonMin : lon[i];
latMax = (latMax > lat[i]) ? latMax : lat[i];
latMin = (latMin < lat[i]) ? latMin : lat[i];
System.println("lonmax = " + lonMax);
System.println("latmax = " + latMax);
System.println("lonmin = " + lonMin);
System.println("latmin = " + latMin);
}

var scaleX = dc.getWidth() / (lonMax - lonMin);
var scaleY = dc.getHeight() / (latMax - latMin);
var scaleXY = (scaleX < scaleY) ? scaleX : scaleY;

dc.setColor(Graphics.COLOR_PURPLE, Graphics.COLOR_TRANSPARENT);
dc.setPenWidth(4);
for(var i=0; i < (lat.size() - 2); i+=2){
var pixelsLon = (lon[i+1] - lon[i]) * scaleXY;
var pixelsLat = (lat[i+1] - lat[i]) * scaleXY;

var displayX = pixelsLon + 120; // screenwidth
var displayY = pixelsLat + 120; //screenheight

dc.fillCircle(displayX, displayY, 3);
if (i == 0) {
var displayXOld = displayX;
var displayYOld = displayY;

} else {
var displayXOld = displayX;
var displayYOld = displayY;
System.println("dxold and dyold" + displayXOld + displayYOld);
System.println("dx and dy" + displayX + displayY);
dc.drawLine(displayXOld, displayYOld, displayX, displayY);
}
}}

So this is the code for drawing the lines and points, I provided it all so you can get a clearer insight into what I'm using. It is slightly modified from what you most recently provided (not a 1-dim array), it draws the points but for some reason not the lines.

For drawing a line you need two points, a starting point and an end point. The line should be drawed and subsequently the starting point should be updated with the end point for advancing to the next loop. So you can't change the order of the statements, i.e. first draw the line and then update the old point.

I've cleaned up and simplyfied your code a little and hope it runs w/o errors ;)

if(lat != null){
    var lonMax = -180.0;
    var lonMin = 180.0;
    var latMax = -90.0;
    var latMin = 90.0;

    for(var i=0; i < lat.size(); i++) {
        lonMax = (lonMax > lon[i]) ? lonMax : lon[i];
        lonMin = (lonMin < lon[i]) ? lonMin : lon[i];
        latMax = (latMax > lat[i]) ? latMax : lat[i];
        latMin = (latMin < lat[i]) ? latMin : lat[i];
        System.println("lonmax = " + lonMax);
        System.println("latmax = " + latMax);
        System.println("lonmin = " + lonMin);
        System.println("latmin = " + latMin);
    }

    var scaleX = dc.getWidth() / (lonMax - lonMin);
    var scaleY = dc.getHeight() / (latMax - latMin);
    var scaleXY = (scaleX < scaleY) ? scaleX : scaleY;

    dc.setColor(Graphics.COLOR_PURPLE, Graphics.COLOR_TRANSPARENT);
    dc.setPenWidth(4);

    var pixelsLon;
    var pixelsLat;
    var displayX;
    var displayY;
    var displayXOld;
    var displayYOld;
    for(var i=0; i < (lat.size() - 2); i+=2){
        pixelsLon = (lon[i+1] - lon[i]) * scaleXY;
        pixelsLat = (lat[i+1] - lat[i]) * scaleXY;

        displayX = pixelsLon + 120; // screenwidth
        displayY = pixelsLat + 120; //screenheight

        dc.fillCircle(displayX, displayY, 3);

        if (i > 0) {
            dc.drawLine(displayXOld, displayYOld, displayX, displayY);
        }
		
        displayXOld = displayX;
        displayYOld = displayY;
        System.println("dxold and dyold" + displayXOld + displayYOld);
        System.println("dx and dy" + displayX + displayY);
    }
}

Right, gotcha, i’ll test it out tomorrow when i’m back at the computer.

Ok it worked, it draws the lines and dots, I had to add “= null” to the variables displayXOld and var displayYOld like so to solve an intialization error:

var displayXOld = null;

var displayYOld = null;

Now that it draws the lines I notice two problems

Note how the background map moves according to your position but the track does not. Heres an example where I change position.

As you can see the purple line is the drawn route, the blue line I added in microsoft paint and marks where the route should be. 

How can I get the purple line to stay where the blue line is?

The second problem is that the route doesn’t appear to be scaled to the map. 

Other than that it is working perfectly.

Again, we are moving further away from your OP. So far the route is only scaled to the screen size. If you want to draw the positions depending on the map size, I recommend you to use the MapSample which is part of the SDK.

C:\User\<User>\AppData\Roaming\Garmin\ConnectIQ\Sdks\<sdk>\samples\MapSample

You appear to be trying to overlay on a MapView. so you will have to use MapPolyLines to keep your track co-ordinated with the scale and positioning of the map.