glsl: matrix qualifier on shader attributes about slang

[farnoy]

Yes I did intend to do that and it's useful with per-instance vertex input attributes. It worked just fine with glsl, I'm pretty sure it's legal.

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On Wed, Jan 17, 2024, 02:13 Yong He ***@***.***> wrote: The fix here is to issue an error message that forbids defining a non-uniform matrix typed parameter. — Reply to this email directly, view it on GitHub <#3447 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACUNUA7ZSIC4VFYDVDBYOTYO4QTRAVCNFSM6AAAAABBZKPIEWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTQOJUG43TIOJTGE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[csyonghe]

Reading matrices from an input stream is very rare. Do you intend this, or do you mean uniform float4x4 mvp?

[csyonghe]

GLSL does not allow matrices as vertex stream elements IIRC.

[csyonghe]

The fix here is to issue an error message that forbids defining a non-uniform matrix typed parameter.

[csyonghe]

The issue here is that the code is being compiled with "column-major" layout, which maps to glsl's "row-major". Can you share you compilation options? Compiling with default row-major layout should get rid of the decoration.

You can also try -emit-spirv-directly and see if it fixes the problem.

[farnoy]

My args are -I src/shaders -g3 -line-directive-mode none -entry main -target glsl -force-glsl-scalar-layout -o out.glsl -- shader.slang

I'm not passing the -matrix-layout-row-major option. Are you saying that if I did pass it, there would be no layout(row_major) or layout(column_major) annotations on these GLSL attributes? I may be approaching it incorrectly in that case, since I translated my GLSL's matrix * vector snippets into mul(matrix, vector) in Slang.

[csyonghe]

You need to either pass -matrix-layout-row-major or specify row_major modifier on the parameter.

[csyonghe]

Closing since the matrix layout qualifier should work here. If not, please reopen.