[openvrml-develop] Re: Transparency

[Damian M. <da...@er...>]

On Fri, 28 Dec 2001, Damian McGuckin wrote:

> In 'ViewerOpenGL::insertTexture', it mentioned
>
> 	// Enable blending if needed
>   	if (d_blend && (nc == 2 || nc == 4))
>     		glEnable(GL_BLEND);
>
> Don't we need an extra
>
> 	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
>
> or does the one in ViewerOpenGL::initialize cover us forever.  There is a
> glDisable(GL_BLEND) in ViewerOpenGL::redraw() and I thought that this
> clobbered the glBlendFunc().  I am a long way away from being an OpenGL
> guru.

And glBlendFunc really wants primitives sorted in Depth order.  Aren't
then loaded them in the order we found them in the VRML file in the first
place. And then, how do we change the depth-sorted order as we move around
within the VRML world?

Questions, questions?

Thanks - Damian (McGuckin)

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