How to program two layers picture?

[Petri]

Hi,

I want to program a picture in a panel which has a map in the background and position coordinates from a GPS as a figure are updated into the map. Map file format can be e.x. bmp. NI example alphablend with x% transparency is something which I could develop further, but I wonder if there is faster way to do that without re-drawing the whole picture every time a position point figure is added to a map ? The same program has to communicate  simultaneously with an instrument for quite intensive amount of measurement values.   

Thanks for any advice. 

/petri

[jr_2005]

If all you want to add to the picture is a set of coordinates, have you considered putting them into a string Text control whose background has been set to transparant?

JR

[Petri]

Sorry that I was unclear. I want to follow positions on the map for a moving vehicle. I can calculate the position from the GPS to correspond the pixel/point on the map. I want also maintain the positions, where vehicle has been, on the map. So, a little point like figure would be nice to present vehicles position now and before.

/petri

[Wolfgang]

So possibly you could use a graph control with a transparent background on top of your picture. Then you add two cursors with possibly different colors to indicate your current and previous car location...

Wolfgang

[ebalci · Accepted solution]

When it comes to drawing lines, isn't the canvas control the best choice?

You can make the background transparent and draw lines to show vehicle's path.

But I'm not sure you can make the lines thick enough to be visible over a colorful background like a map.

[Petri]

Hi S. Eren BALCI,

Yes, canvas was the best solution. Thanks.

Regards,

Petri