Function _EmitDeclaration

pxr/imaging/hdSt/codeGen.cpp:3409–3523

}

static void _EmitDeclaration(
    HioGlslfxResourceLayout::ElementVector *elements,
    TfToken const &name,
    TfToken const &type,
    HdStBinding const &binding,
    bool isWritable,
    int arraySize)
{
    /*
      [vertex attribute]
         layout (location = <location>) in <type> <name>;
      [uniform]
         layout (location = <location>) uniform <type> <name>;
      [SSBO]
         layout (std430, binding = <location>) buffer buffer_<location> {
            <type> <name>[];
         };
      [Bindless Uniform]
         layout (location = <location>) uniform <type> *<name>;

     */
    HdStBinding::Type bindingType = binding.GetType();

    if (!TF_VERIFY(!name.IsEmpty())) return;
    if (!TF_VERIFY(!type.IsEmpty(),
                      "Unknown dataType for %s",
                      name.GetText())) return;

    if (arraySize > 0) {
        if (!TF_VERIFY(bindingType == HdStBinding::UNIFORM_ARRAY             ||
                       bindingType == HdStBinding::DRAW_INDEX_INSTANCE_ARRAY ||
                       bindingType == HdStBinding::UBO                       ||
                       bindingType == HdStBinding::SSBO                      ||
                       bindingType == HdStBinding::BINDLESS_SSBO_RANGE       ||
                       bindingType == HdStBinding::BINDLESS_UNIFORM)) {
            // XXX: SSBO and BINDLESS_UNIFORM don't need arraySize, but for the
            // workaround of UBO allocation we're passing arraySize = 2
            // for all bindingType.
            return;
        }
    }

    // layout qualifier (if exists)
    uint32_t location = binding.GetLocation();
    switch (bindingType) {
        case HdStBinding::VERTEX_ATTR:
        case HdStBinding::DRAW_INDEX:
        case HdStBinding::DRAW_INDEX_INSTANCE:
            _AddVertexAttribElement(elements,
                                    /*name=*/name,
                                    /*dataType=*/_GetPackedType(type, false),
                                    location);

            break;
        case HdStBinding::DRAW_INDEX_INSTANCE_ARRAY:
        {
            for(int i = 0; i < arraySize;i++) {
                _AddVertexAttribElement(elements,