Shader issue: #extension repeated in shader

[Chien Yang]

Hi Johan,

Can you please file a JIRA for this?

Thanks,
- Chien

On 12/30/15 04:33, Johan Vos wrote:
> When upgrading a Nexus 6 from Android 5.1.1 to Android 6, the JavaFX 3D
> stopped working.
> The relevant error is this:
>
> java.lang.RuntimeException: Error creating fragment shader
> in
> com.sun.prism.es2.ES2Shader.createFromSource
>
> The shader compilation failed with this error:
> GLSL compile error:  Extension directives must occur before any
> non-preprocessor tokens.
> which occurs in
>
> When debugging this, it seems the fragment shader passed
> to glCtx.compileShader is created by ES2PhongShader.getShader() which
> starts from main1Light.frag and which will do a replaceAll for a number of
> statements which will replace those statements with other shader code that
> also contains an #extension directive.
>
> As a result, the resulting shader source contains a number of identical
> #extension directives. It seems the latest drivers on Android are much more
> strict in compiling shaders, and they complain about the position of the
> extension directives.
>
> It seems to me some post-processing needs to be done on the result of the
> replaceAll() statements when creating the fragment shader in
> ES2PhongShader.getShader(ES2MeshView meshView, ES2Context context)
>
> I did a quick and dirty workaround for this in the 8u-dev-tree on
> javafxports:
> https://bitbucket.org/javafxports/8u-dev-rt/commits/a84eb188c73ff60b68c016f14b6ebf85449a6bbe
>
> With this patch, JavaFX 3D works again on Android, but it is not the best
> post-processing solution.
>
> Another solution might be to remove the extension directives from the
> individual files in glsl and add them at the end of the processing chain?
>
> - Johan