Shadow plane - which blend mode?

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Cancerian (Posted 2005) [#1]

Hi, I'm trying to create a simple shadow plane to sit beneath my player object. This is just the old-school shadow blob like the old Resident Evil games. I've tried a dark gray circle on a black background, I've tried a black circle on a white background and neither one will blend to create the effect I want. I just want the circular shadow to show and not the rest of the texture. The shadow has to be dark coloured. Any adice? Thanks!

Rob Farley (Posted 2005) [#2]

Multiply blend. Use a grey circle on a white background and blur it to buggery.

Raitsun (Posted 2005) [#3]

The Texture should contain Alpha-Information, you can make parts of a picture transparent with Photoshop for example. If you just make a circle that is NOT totally black on totally black Background, that should work, too. Just Load the texture with the "masked" tag: LoadTexture("picture.pic", 1+4) Raitsun

Raitsun (Posted 2005) [#4]

Or solve this problem in an intelligent manner and listen to what Rob says ^^

Sledge (Posted 2005) [#5]

I tend to use Multiply 2 (mode 5)* *Edit: Mind you, that was for generating a shadowplane in realtime... I'll have to have a rummage as it's been a while and I never comment properly. Normal multiply should definately be useful to you, Multiply 2 simlpy blends so that color 128,128,128 has no effect and anything brighter lightens while any area less bright darkens. God only knows what I was up to.

Cancerian (Posted 2005) [#6]

I could have sworn I tried that before but gray blob on the white background works for me now. I think I had blurred too much and turned the white edges into light grey because you used to be able to clearly see the edges of the shadow polygon. But as I said, it works perfectly now so thank-you all for your help!

jfk EO-11110 (Posted 2005) [#7]

I use the alpha channel of a 32 Bit TGA for the circle, where the RGB Channels are simply black. So I have to alphablend this this texture. Probably Multiply Blending is better, maybe it won't produce Alpha Z-order problems, as Alpha-Shadows usually do when there's more Alpha Stuff in the scene.