transparent text in opengl

[atcdevil]

Text doesn't render transparent for me using OpenGL + setOverrideColor + enableOverrideColor. If alpha is 0... the text is invisible, if it is anything greater it is opaque, nothing in between.

Is this a known issue?

EDIT:

I went into CVideoOpenGL.cpp in draw2DImage:
I changed the setRenderStates2DMode calls to:

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if (useAlphaChannelOfTexture) setRenderStates2DMode(color.getAlpha() < 255, true, true);
else setRenderStates2DMode(color.getAlpha() < 255, true, false);

Then in setRenderStates2DMode, in the case that texture and alphaChannel are true, I changed the body to:

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glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0);

Enabling blending was originally commented out without an explanation, anyone know why that is?

EDIT: See below for update...

[niko]

I think it is simply a bug, I did not implement the OpenGL-version very perfectly. Your code fixes all the problems?

[atcdevil]

It works in my simple test program. I haven't done any comprehensive testing. I can get back to you on that as I use it more.

I also tweaked that 2nd snippet a little bit to be:

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if(alpha) {
	glEnable(GL_BLEND);
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
}
else {
	glDisable(GL_BLEND);
}
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0);

[Electron]

there are two sections that begin if(alpha). Whcih one are did you change?