Shapes2D doesn't work with VR with single pass instanced

[all-iver]

But according to a user it can be made to work easily by following the instructions on this page: https://docs.unity3d.com/Manual/SinglePassInstancing.html

[MathiasWorm]

thank @all-iver

the solution looks like that:

open your shapes.shader file and insert the lines flagged with //Inserted

struct appdata_t {
    float4 vertex : POSITION;
    float4 color : COLOR;
    float2 texcoord : TEXCOORD0;
    UNITY_VERTEX_INPUT_INSTANCE_ID  // Inserted
    };
            
struct v2f {
    float4 pos : SV_POSITION;
    float2 uv : TEXCOORD0;
    float4 modelPos : TEXCOORD1;
    fixed4 color : COLOR;

    UNITY_VERTEX_OUTPUT_STEREO  // Inserted
    };

v2f vert(appdata_t v) {
    v2f o;

    UNITY_SETUP_INSTANCE_ID(v);     // Inserted
    UNITY_INITIALIZE_OUTPUT(v2f, o);    // Inserted
    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);   // Inserted

    o.pos = UnityObjectToClipPos(v.vertex);
    // translate input uv coords (which are from 0 - 1 on either dimension) to something more 
    // useful (-0.5 to 0.5).
    o.uv = v.texcoord.xy - 0.5;
    o.modelPos = v.vertex;
    // hijack modelPos.z to be distance from camera plane since it 
    // isn't being used for anything else.  used for pixel size.
    o.modelPos.z = -UnityObjectToViewPos(v.vertex).z;
    // for Unity versions < 5.4.0f3
    // o.modelPos.z = -mul(UNITY_MATRIX_MV, v.vertex).z;
    o.color = v.color;
    return o;
    }