C++ TType::isStruct方法代码示例

// Recursively merge the implicit array sizes through the objects' respective type trees.
void TIntermediate::mergeImplicitArraySizes(TType& type, const TType& unitType)
{
    if (type.isImplicitlySizedArray() && unitType.isArray()) {
        int newImplicitArraySize = unitType.isImplicitlySizedArray() ? unitType.getImplicitArraySize() : unitType.getOuterArraySize();
        if (newImplicitArraySize > type.getImplicitArraySize ())
            type.setImplicitArraySize(newImplicitArraySize);
    }

    // Type mismatches are caught and reported after this, just be careful for now.
    if (! type.isStruct() || ! unitType.isStruct() || type.getStruct()->size() != unitType.getStruct()->size())
        return;

    for (int i = 0; i < (int)type.getStruct()->size(); ++i)
        mergeImplicitArraySizes(*(*type.getStruct())[i].type, *(*unitType.getStruct())[i].type);
}

    int resolveInOutLocation(EShLanguage /*stage*/, const char* /*name*/, const TType& type, bool /*is_live*/) override
    {
        // kick out of not doing this
        if (!doAutoLocationMapping)
            return -1;

        // no locations added if already present, or a built-in variable
        if (type.getQualifier().hasLocation() || type.isBuiltIn())
            return -1;

        // no locations on blocks of built-in variables
        if (type.isStruct()) {
            if (type.getStruct()->size() < 1)
                return -1;
            if ((*type.getStruct())[0].type->isBuiltIn())
                return -1;
        }

        // Placeholder.
        // TODO: It would be nice to flesh this out using 
        // intermediate->computeTypeLocationSize(type), or functions that call it like
        // intermediate->addUsedLocation()
        // These in turn would want the intermediate, which is not available here, but
        // is available in many places, and a lot of copying from it could be saved if
        // it were just available.
        return 0;
    }

// Recursively figure out how many bytes of xfb buffer are used by the given type.
// Return the size of type, in bytes.
// Sets containsDouble to true if the type contains a double.
// N.B. Caller must set containsDouble to false before calling.
unsigned int TIntermediate::computeTypeXfbSize(const TType& type, bool& containsDouble) const
{
    // "...if applied to an aggregate containing a double, the offset must also be a multiple of 8, 
    // and the space taken in the buffer will be a multiple of 8.
    // ...within the qualified entity, subsequent components are each 
    // assigned, in order, to the next available offset aligned to a multiple of
    // that component's size.  Aggregate types are flattened down to the component
    // level to get this sequence of components."

    if (type.isArray()) {        
        // TODO: perf: this can be flattened by using getCumulativeArraySize(), and a deref that discards all arrayness
        assert(type.isExplicitlySizedArray());
        TType elementType(type, 0);
        return type.getOuterArraySize() * computeTypeXfbSize(elementType, containsDouble);
    }

    if (type.isStruct()) {
        unsigned int size = 0;
        bool structContainsDouble = false;
        for (int member = 0; member < (int)type.getStruct()->size(); ++member) {
            TType memberType(type, member);
            // "... if applied to 
            // an aggregate containing a double, the offset must also be a multiple of 8, 
            // and the space taken in the buffer will be a multiple of 8."
            bool memberContainsDouble = false;
            int memberSize = computeTypeXfbSize(memberType, memberContainsDouble);
            if (memberContainsDouble) {
                structContainsDouble = true;
                RoundToPow2(size, 8);
            }
            size += memberSize;
        }

        if (structContainsDouble) {
            containsDouble = true;
            RoundToPow2(size, 8);
        }
        return size;
    }

    int numComponents;
    if (type.isScalar())
        numComponents = 1;
    else if (type.isVector())
        numComponents = type.getVectorSize();
    else if (type.isMatrix())
        numComponents = type.getMatrixCols() * type.getMatrixRows();
    else {
        assert(0);
        numComponents = 1;
    }

    if (type.getBasicType() == EbtDouble) {
        containsDouble = true;
        return 8 * numComponents;
    } else
        return 4 * numComponents;
}

// Recursively figure out how many locations are used up by an input or output type.
// Return the size of type, as measured by "locations".
int TIntermediate::computeTypeLocationSize(const TType& type) const
{
    // "If the declared input is an array of size n and each element takes m locations, it will be assigned m * n 
    // consecutive locations..."
    if (type.isArray()) {
        // TODO: perf: this can be flattened by using getCumulativeArraySize(), and a deref that discards all arrayness
        TType elementType(type, 0);
        if (type.isImplicitlySizedArray()) {
            // TODO: are there valid cases of having an implicitly-sized array with a location?  If so, running this code too early.
            return computeTypeLocationSize(elementType);
        } else
            return type.getOuterArraySize() * computeTypeLocationSize(elementType);
    }

    // "The locations consumed by block and structure members are determined by applying the rules above 
    // recursively..."    
    if (type.isStruct()) {
        int size = 0;
        for (int member = 0; member < (int)type.getStruct()->size(); ++member) {
            TType memberType(type, member);
            size += computeTypeLocationSize(memberType);
        }
        return size;
    }

    // ES: "If a shader input is any scalar or vector type, it will consume a single location."

    // Desktop: "If a vertex shader input is any scalar or vector type, it will consume a single location. If a non-vertex 
    // shader input is a scalar or vector type other than dvec3 or dvec4, it will consume a single location, while 
    // types dvec3 or dvec4 will consume two consecutive locations. Inputs of type double and dvec2 will 
    // consume only a single location, in all stages."
    if (type.isScalar())
        return 1;
    if (type.isVector()) {
        if (language == EShLangVertex && type.getQualifier().isPipeInput())
            return 1;
        if (type.getBasicType() == EbtDouble && type.getVectorSize() > 2)
            return 2;
        else
            return 1;
    }

    // "If the declared input is an n x m single- or double-precision matrix, ...
    // The number of locations assigned for each matrix will be the same as 
    // for an n-element array of m-component vectors..."
    if (type.isMatrix()) {
        TType columnType(type, 0);
        return type.getMatrixCols() * computeTypeLocationSize(columnType);
    }

    assert(0);
    return 1;
}

    int resolveInOutLocation(EShLanguage stage, const char* /*name*/, const TType& type, bool /*is_live*/) override
    {
        // kick out of not doing this
        if (!doAutoLocationMapping())
            return -1;

        // no locations added if already present, or a built-in variable
        if (type.getQualifier().hasLocation() || type.isBuiltIn())
            return -1;

        // no locations on blocks of built-in variables
        if (type.isStruct()) {
            if (type.getStruct()->size() < 1)
                return -1;
            if ((*type.getStruct())[0].type->isBuiltIn())
                return -1;
        }

        // point to the right input or output location counter
        int& nextLocation = type.getQualifier().isPipeInput() ? nextInputLocation : nextOutputLocation;

        // Placeholder. This does not do proper cross-stage lining up, nor
        // work with mixed location/no-location declarations.
        int location = nextLocation;
        int typeLocationSize;
        // Don’t take into account the outer-most array if the stage’s
        // interface is automatically an array.
        if (type.getQualifier().isArrayedIo(stage)) {
                TType elementType(type, 0);
                typeLocationSize = TIntermediate::computeTypeLocationSize(elementType, stage);
        } else {
                typeLocationSize = TIntermediate::computeTypeLocationSize(type, stage);
        }
        nextLocation += typeLocationSize;

        return location;
    }