Edges on transparent texture

[ozRocker]

Does anyone know why the edges of my transparent texture have red lines on it?  Is there a way to prevent it from happening?

https://www.babylonjs-playground.com/#YTHP9D

[GameMonetize]

Just wrap your texture using clamp

https://www.babylonjs-playground.com/#YTHP9D#1

 

[ozRocker]

7 hours ago, Deltakosh said:

Just wrap your texture using clamp

https://www.babylonjs-playground.com/#YTHP9D#1

 

Thank you!!

[Wingnut]

Weird solution. (Wingy checks texture transparent pixel @ 0, 0 [lower left corner] to see if a mosquito turd got jammed in there.)

I wonder why this texture needs wrap-clamping.  hmm.  Oh, it was upside-down.  THAT's why it needed... errr... no.  *scratch scratch*

It's because pixel 0,0 is transparent.  It's fooling some BJS code somewhere, I bet.  (Wingy activates his SUPER-DOOPER electron microscope, and examines some shader code.  It causes him pink-eye.)

I dunno.  Something smells fishy, here.    How 'bout you, Oz?  Are you going to swallow this solution without coughing-up a yak hairball?  (without wondering "what the heck?")

Things that make ya go "hmm".

[ozRocker]

24 minutes ago, Wingnut said:

I dunno.  Something smells fishy, here.    How 'bout you, Oz?  Are you going to swallow this solution without coughing-up a yak hairball?  (without wondering "what the heck?")

Things that make ya go "hmm".

I will gladly swallow this solution without question

[GameMonetize]

It is not "fishy"  Here is the explanation:

pixels on the edge will have an uv of 0,0 (or 0,1 on the bottom). BUT we are using linear filtering which means that more than one texel is read from the texture.

 

Let's just suppose the bilinear uses a box approach. for uv = 0,0 it will actually read 0,0 and -epsilon, 0 and +epsilon,0 and so on.. 

 

If wrap is enabled the -epsilon will be converted to 0.99999 so it will capture a bit of red. 

 

Does it make sense?

[Wingnut]

ah ha!!!  hehe.  Thx dk!