overlaying images with transparency..

[alanshort]

Hi

I'm tryting to create a weather map. Currently, I have two images, the map and an arrow to show wind direction.

I would like to use C# to load the map image(bmp) as a background then paste the arrow on top of the map.

The arrow is currently a png with transparency.

Is this possible ??

Also, is there an easy way to rotate the arrow image in C#??

cheers
A

 

[alanshort]

I'm now using a bmp and I've got this so far which works however, the arrow is not being displayed correctly. It's being resized for some reason... any ideas ??


public static void updateWeatherMap ()
{
Graphics g;
Image weatherMap = Image.FromFile (@"outputMap/_weathermap.bmp"
Bitmap wf3 = (Bitmap)Image.FromFile(@"outputMap/wf3.bmp"

wf3.MakeTransparent(Color.White);

g = Graphics.FromImage(weatherMap);

g.DrawImage(wf3,150,50);

weatherMap.Save(@"outputMap/weathermap1.png",ImageFormat.Png);

g.Dispose();
wf3.Dispose();
weatherMap.Dispose();
}