hard to diagnose error in shader

[Geokureli]

hard to diagnose error in shader

[giuppe]

It's not flixel's fault. The #pragma header directive is preprocessed by a simple string replace, here:

openfl/src/openfl/utils/_internal/ShaderMacro.hx

Line 106 in e1fd1a0

glFragmentSource = StringTools.replace(glFragmentSource, "#pragma header", glFragmentHeader);

Missing the space means that the substitution won't take place, and the resulting shader string is sent as-is to the opengl driver. The error message is GPU-vendor-dependent: and some vendors might also treat it as a warning and/or just skip the faulty line, so you could have a shader working fine on your GPU and then failing for some of your players.

Probably the only way to catch this type of errors independently of opengl drivers is to use a Haxe based GLSL parser/compiler like Heaps' HXSL.

[Geokureli]

I'm mainly surprised it's not giving this error:

'pragmaheader' : invalid directive name