draw2dImage Alpha

[kevinsbro]

Is it possible to use the texture's alpha values when drawing 2D images?
I know you can get it so that either all or none of certain pixels are transparent, but what if I want a value in between for each pixel?

[Nadro]

draw2DImage allow enable alpha blending, so all values between 0-255 are available for pixels related to alpha.

[kevinsbro]

I know that you can use alpha on the vertex level, but I want to be able to load a texture with an alpha channel and have it use that for alpha blending.

Currently, if you try and do this now, it clamps the value to all invisible or all visible.

[Nadro]

Which Irrlicht version do you use?

[kevinsbro]

I'm currently using Irrlicht 1.8.

I've taken a look at the source code on the direct x side of things and can tweak the code in CD3D9Driver::setRenderStates2DMode to change the alpha blending between the vertex alpha and texture alpha, but there seems to be something going on at the actual texture alpha. Somewhere else in the code the texture alpha must be getting clamped to either all (255) or none (0).

Can someone help me find where in the source this is happening?
The main method to look at is CD3D9Driver::draw2DImage

[vroad]

Have you look at the documentation?
Just pass true to 'useAlphaChannelOfTexture' parameter.
http://irrlicht.sourceforge.net/docu/cl ... e526bbcdb3