Glowing and hollowed out-type sprites

Hey, I have some sprites that are causing me grief. Here’s my problem;

Let’s say you make a black ‘o’ shaped sprite in Photoshop, you make that ‘glow’ (if black can glow, but blur it and layer on top with 20% opacity or so). Now you will have some semitransparent areas, bring this into UE and create sprites using ‘extract sprites’. I am getting mixed results first of all, some of my shapes which have a hollowed out area in the middle (again, such as an ‘o’ or ‘b’) will be fully opaque in the middle. In this example it means a fully black circle.

I expect this to work better when not making anything glow, and just use sprites fully opaque or not (right?). How can I create this though? Post process won’t work AFAIK as that’s depending on superbright colours to kick in.

It be interesting to hear if I can also edit my sprites in any way to edit their look if the opacity is causing issues within an enclosed area.

Playing with the alpha threshold does nothing in any of the rendering modes from my testing so far.

Is this impossible to do with sprites?

Thanks.

I think I can make the decision how to move forward by just knowing if a sprite pixel has to be either fully opaque or completely see through.

If so I’d imagine a flat poly with a normal material will have to do.

Cheers.

Could you elaborate on what precisely you are trying to do, I am kind of lost in your text. Also an image would be nice.

Yeah I thought I might’ve been confusing people a bit, thanks for asking for clarification.

This is the effect I want to achieve:

http://www.gimpusers.com/system/tutorial_steps/773/6-original.png

If I run the ‘extract sprites’ on an image like that (can’t show you my exact image and the result as I’m at work) the inside of the ‘o’ becomes fully opaque even if that part is ranging between 0-40% transparent. Its alpha will be like a solid ball and not a doughnut essentually.

Again, I think the main question is whether a sprite can be partially see-through or not. :confused:

Thanks!

Black = 0 opacity while White = 100% opacity.

By default if you set up your material to masked and you plug in your masked version (Example the white text only) you should not get your example working properly. Because if you click at the actual material by default there is a floor value that controls the minimum masking. 0.333300 is the default value.

The name of that should be “Opacity Mask Clip Value”. Play with that while previewing to see how that affects your material. Btw i wouldn’t bake the glow leak in your text, The engine will create that glow after you input your color value on emissive (If R, G or B >= 1).
Plug your opacity mask or w/e in the input then go ahead and create an RGB node and input that with your desired color to your emissive. That would get you started.

Hope that made it clear. If you still have issues or didn’t get what i said let me know. When u get later on home if it’s not working post again an image of your texture and your material set up it self along with what you are using for blend and shading modes.

Oh and yes i know what u mean by becoming fully opaque, I need to see the actual texture again, However if it becomes fully opaque it means it generates too much emissive color in that area.

Heya,

My guess is that you are using a masked material (which is the default for sprites). If you have smooth gradients in alpha then you need to switch to using a translucent material instead. There is one in the Paper2D package or you can easily make one yourself using the SpriteTexture node.

Cheers,
Michael Noland

Your explanation was much better than mine lol. If indeed he is using that.

Great, worked a charm! :slight_smile: