Outline with fade-out?

[lukas____]

Hey guys,
I looked for an outline shader and found this one: http://www.allpiper.com/2d-selection-ou ... in-libgdx/
Works great! But I need an alpha transition/fade-out to achieve a glow-effect.
Do you have an idea?

[Hangman]

Just add a new uniform value for alpha, or change the existing Vec3 u_color to Vec4.
Multiply both alpha values before you give it to gl_FragColor.

[RafaSKB]

Just something to keep in mind about performance: When using Shader code, ifs and fors can make the code very slow, because the GPU usually processes many pixels at once with the same code, unless there are fors and ifs.