VertexAlpha & Entity Alpha?

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John Pickford (Posted 2007) [#1]

Does using vertex alpha stop entityalpha from working? I'm buildinga mesh in realtime which uses vertexalpha and it seems to be immune to the effects of entityalpha till it reaches zero (object disappears). Is there any way around this? JP

Beaker (Posted 2007) [#2]

Seems to work ok in Blitz3D. Are you sure you are using a float for the alpha value? Is it between 0.0 and 1.0?

John Pickford (Posted 2007) [#3]

Of course.

Beaker (Posted 2007) [#4]

Oh wait! My mistake, it isn't working in Blitz3D either, so I presume its a feature rather than bug. You can of course do global alpha yourself using the vertex alpha.

John Pickford (Posted 2007) [#5]

It's hard to imagine this was done on purpose. Oh well, I'll have to think of something else.

Gabriel (Posted 2007) [#6]

How were you hoping it would behave? As a multiplier or just as a quick way of setting the alpha of each vertex?

John Pickford (Posted 2007) [#7]

As a multiplier. That would be consistent. It's not like VertexColour stops lighting from working.

simonh (Posted 2007) [#8]

The same thing happens in MiniB3D. When vertex colours are enabled it seems the material alpha just gets ignored by the hardware.

John Pickford (Posted 2007) [#9]

So it's a hardware\DX artifact rather than a bug in the engine?

simonh (Posted 2007) [#10]

Well MiniB3D is OpenGL so it suggest it's a hardware thing.