Shadergraph update broke `w` usage

[timmybo5]

Describe the bug

A recent update of Shadergraph broke one of my already working shaders by changing the usage of w in the compiled shader code.

shaders/skins/wb_texturewrap.shader : SM 5.0 (D3D11), Pixel Shader, Non-Zero Combos: ---
shaders/skins/wb_texturewrap.shader(79,20-29): error X3018: invalid subscript 'w'

Old compiled code:

    float4 MainPs( PixelInput i ) : SV_Target0
    {
        Material m;
        m.Albedo = float3( 1, 1, 1 );
        m.Normal = TransformNormal( i, float3( 0, 0, 1 ) );
        m.Roughness = 1;
        m.Metalness = 0;
        m.AmbientOcclusion = 1;
        m.TintMask = 1;
        m.Opacity = 1;
        m.Emission = float3( 0, 0, 0 );
        m.Transmission = 0;

        float local0 = i.vPositionSs.x;
        float local1 = i.vPositionSs.y;
        float4 local2 = float4( local0, local1, local1, local1 );
        float local3 = i.vPositionSs.w;

New compiled code:

    float4 MainPs( PixelInput i ) : SV_Target0
    {
        Material m;
        m.Albedo = float3( 1, 1, 1 );
        m.Normal = TransformNormal( i, float3( 0, 0, 1 ) );
        m.Roughness = 1;
        m.Metalness = 0;
        m.AmbientOcclusion = 1;
        m.TintMask = 1;
        m.Opacity = 1;
        m.Emission = float3( 0, 0, 0 );
        m.Transmission = 0;

        float2 local0 = CalculateViewportUv( i.vPositionSs.xy );
        float local1 = local0.x;
        float local2 = local0.y;
        float4 local3 = float4( local1, local2, 0, 0 );
        float local4 = local0.w; <------------------------------------ line 79

Reproduce with:

[aylaylay]

This was an obvious typo in the Split node. Someone changed Screen Position to return a float2 so that's why this error has now popped up for you.

Also please note because of the Screen Position change, you'll have to change your shader. I believe you don't need to do the split, combine and divide anymore.. just plug the screenposition into the texture coord input.

[timmybo5]

The divide by w gives a special effect basically wrapping it around the meshes ignoring the uv's, without that it's just a normal screenspace effect

I need it to create this sort of skins, not sure how it would be possible otherwise.

[aylaylay]

Yeah sorry, Screen Position node was changed to do something else and I don't know why. I might revert it.

[aylaylay]

Alright, I've reverted ScreenPosition to do what it was doing before and added common accessors so you don't need to bother splitting and combining. Here's how to do what you were doing before. Hope this helps.

[timmybo5]

Even better! Works perfectly :)