Sprite.Draw2D and Alphablending?

I'm trying to do alphablended sprites (not color keyed sprites), but it doesn't seems to works. I tried to load .dds with alpha channel and .bmp (32bpp, last channel should be obviously alpha, but i don't know if TextureLoader.FromFile() understand the last channel as an alpha channel).

I've put the device's renderstate at alphablendingenable = true (don't have any PS GFX card). But it doesn't seems to work. Am I missing something Maybe should I try to put some texturestage state But which value should I use

System specs:
Windows 2000 SP4
Ati 7200 AIW
Dx 9 SDK (Apr 2005 release, jun release only works on XP and above)
Visual C# 2005 (with Framework .Net beta 2)

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Sprite.Draw2D and Alphablending?

Jeremy Grand
Make sure you set the Color in your Draw to Color.White

This will allow all channels to pass through. If you set this to 0 or black then the ARGB (0,0,0,0) will be multiplied to each pixel of your image.

Here is some sample code: This sample draws a red line from top left to bottom right.

Bitmap myImage = new Bitmap(100, 100);
Graphics g = Graphics.FromImage(myImage);
g.Clear(Color.FromArgb(0)); //Fill background with a transparent color
g.DrawLine(new Pen(Color.Red, 10),1,1,100,100);
Texture myTexture = new Texture(device, myImage, Usage.None, Pool.Managed);
Sprite sprite = new Sprite(device);
sprite.Begin(SpriteFlags.AlphaBlend);
sprite.Draw2D(myTexture, new Point(0, 0), 0, new Point(0, 0), Color.White);
sprite.End();

Hope this helps.

Andrew
dongjunming
So i've tested some of your suggestions:

PNG with SpriteFlags.None: No transparency
PNG with SpriteFlags.AlphaBlending: No image displayed (very curious, isn't it )

I surely miss something, but I don't know what. My last experience with Direct3D was with DirectX 6 (and C++ of course). I'm a bit lost with managed DirectX :/.
Werner de Jong
Try to use PNG files. Been there done that!

[]s
Dan Ward
When you call Sprite.Begin are you passing the AlphaBlend flag If you're using the Sprite interface you don't need to touch the renderstates or texturestages yourself.
Sprite.Draw2D and Alphablending?

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