I'm working with Visual C# 2010 Express and SDL.net graphics library.
I try to paint on winform with SurfaceControl Class, and can't create an empty surface to draw on. I found only one working example with bitmap, although there is such method in http://cs-sdl.sourceforge.net/apidocs/html/class_sdl_dot_net_1_1_graphics_1_1_surface.html
Surface (int width, int height) // "Create surface of a given width and height."`
My code:
private void surfaceControl1_Click(object sender, EventArgs e)
{
Surface surf = new Surface((Bitmap)Bitmap.FromFile("example.png"));
surfaceControl1.Blit(surf, new Point(0, 0));
surfaceControl1.Blit(surf, new Point(20, 20));
// this works
Surface surf2 = new Surface(20, 20); // <- throws exception on click
surf2.Fill(Color.White);
surfaceControl1.Blit(surf2);
}
Also tried:
Surface surf2 = new Surface(this.surfaceControl1.Width,this.surfaceControl1.Height);
NullReferenceException was unhandled Object reference not set to an instance of an object. Troubleshooting tips: Use the "new" keyword to create an object instance.. etc.
SDl.net has example files with sources, it uses same method to initialize surface variable as i do, but mine throws exception. Can't find examples or tutorials with SurfaceControl usage. Any ideas what i am doing wrong?
Also found this tutorial http://www.microbasic.net/2011/08/using-sdl-with-c/ It uses this code:
Surface surface = new Surface(100, 100); //same error here
Surface item = new Surface((Bitmap)Bitmap.FromFile(“example.png”));
surface.Blit(item, new Point(0, 0));
surface.Blit(item, new Point(20, 20));
this.surfaceControl.Blit(surface);
But this code also throws same exception.
More information: I managed to launch sdl.net SdlDotNetCDPlayer example, and surprizingly it throws same exception! Though i had these examples working on my laptop half year ago.
protected override void OnResize(EventArgs e)
{
try
{
surf =
new Surface(
this.surfaceControl.Width,
this.surfaceControl.Height); //exception error
base.OnResize(e);
}
catch (AccessViolationException ex)
{
Console.WriteLine(ex.StackTrace);
}
}
It may be a bug in the SdlDotNet.dll. When I reference version 6.1 of the DLL, I receive the same run-time error. When I reference version 5.0 of the DLL, it runs fine.
Note that v5 uses a slightly different set of initializes for the Surface, so you may need to tweak your code.