types.h

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//
// Copyright 2016 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
#ifndef PXR_BASE_VT_TYPES_H
#define PXR_BASE_VT_TYPES_H
 
 
#include "pxr/pxr.h"
#include "pxr/base/vt/api.h"
#include "pxr/base/vt/traits.h"
#include "pxr/base/arch/inttypes.h"
#include "pxr/base/gf/declare.h"
#include "pxr/base/gf/half.h"
#include "pxr/base/gf/timeCode.h"
#include "pxr/base/tf/meta.h"
#include "pxr/base/tf/preprocessorUtilsLite.h"
#include "pxr/base/tf/token.h"
 
#include <cstddef>
#include <cstring>
#include <string>
 
PXR_NAMESPACE_OPEN_SCOPE
 
// Help ensure TfToken is stored in local storage in VtValue by indicating it is
// cheap to copy (just refcount operations).
VT_TYPE_IS_CHEAP_TO_COPY(TfToken);
 
// GfTimeCode supports value transformations.
VT_VALUE_TYPE_CAN_TRANSFORM(GfTimeCode);
 
// Value types.
 
#define VT_FLOATING_POINT_BUILTIN_VALUE_TYPES \
((      double,                Double )) \
((      float,                 Float  )) \
((      GfHalf,                Half   ))
 
#define VT_TIMECODE_VALUE_TYPES \
((      GfTimeCode,            TimeCode ))
 
#define VT_INTEGRAL_BUILTIN_VALUE_TYPES     \
((      bool,                  Bool   ))    \
((      char,                  Char   ))    \
((      unsigned char,         UChar  ))    \
((      short,                 Short  ))    \
((      unsigned short,        UShort ))    \
((      int,                   Int    ))    \
((      unsigned int,          UInt   ))    \
((      int64_t,               Int64  ))    \
((      uint64_t,              UInt64 ))
 
#define VT_VEC_INT_VALUE_TYPES         \
((      GfVec4i,             Vec4i  )) \
((      GfVec3i,             Vec3i  )) \
((      GfVec2i,             Vec2i  )) 
 
#define VT_VEC_HALF_VALUE_TYPES        \
((      GfVec4h,             Vec4h  )) \
((      GfVec3h,             Vec3h  )) \
((      GfVec2h,             Vec2h  ))
 
#define VT_VEC_FLOAT_VALUE_TYPES       \
((      GfVec4f,             Vec4f  )) \
((      GfVec3f,             Vec3f  )) \
((      GfVec2f,             Vec2f  ))
 
#define VT_VEC_DOUBLE_VALUE_TYPES      \
((      GfVec4d,             Vec4d  )) \
((      GfVec3d,             Vec3d  )) \
((      GfVec2d,             Vec2d  ))
 
#define VT_VEC_VALUE_TYPES   \
    VT_VEC_INT_VALUE_TYPES   \
    VT_VEC_HALF_VALUE_TYPES  \
    VT_VEC_FLOAT_VALUE_TYPES \
    VT_VEC_DOUBLE_VALUE_TYPES
 
#define VT_MATRIX_FLOAT_VALUE_TYPES      \
((      GfMatrix4f,          Matrix4f )) \
((      GfMatrix3f,          Matrix3f )) \
((      GfMatrix2f,          Matrix2f )) \
 
#define VT_MATRIX_DOUBLE_VALUE_TYPES     \
((      GfMatrix4d,          Matrix4d )) \
((      GfMatrix3d,          Matrix3d )) \
((      GfMatrix2d,          Matrix2d ))
 
#define VT_MATRIX_VALUE_TYPES            \
    VT_MATRIX_FLOAT_VALUE_TYPES          \
    VT_MATRIX_DOUBLE_VALUE_TYPES         \
 
#define VT_GFRANGE_VALUE_TYPES                 \
((      GfRange3f,           Range3f        )) \
((      GfRange3d,           Range3d        )) \
((      GfRange2f,           Range2f        )) \
((      GfRange2d,           Range2d        )) \
((      GfRange1f,           Range1f        )) \
((      GfRange1d,           Range1d        ))
 
#define VT_RANGE_VALUE_TYPES                   \
    VT_GFRANGE_VALUE_TYPES                     \
((      GfInterval,          Interval       )) \
((      GfRect2i,            Rect2i         ))
 
#define VT_STRING_VALUE_TYPES            \
((      std::string,           String )) \
((      TfToken,               Token  ))
 
#define VT_QUATERNION_VALUE_TYPES           \
((      GfQuath,             Quath ))       \
((      GfQuatf,             Quatf ))       \
((      GfQuatd,             Quatd ))       \
((      GfQuaternion,        Quaternion ))
 
#define VT_DUALQUATERNION_VALUE_TYPES       \
((      GfDualQuath,         DualQuath ))   \
((      GfDualQuatf,         DualQuatf ))   \
((      GfDualQuatd,         DualQuatd ))
 
#define VT_NONARRAY_VALUE_TYPES                 \
((      GfFrustum,           Frustum))          \
((      GfMultiInterval,     MultiInterval))
 
// Helper macros for extracting bits from a type tuple.
#define VT_TYPE(elem) \
TF_PP_TUPLE_ELEM(0, elem)
#define VT_TYPE_NAME(elem) \
TF_PP_TUPLE_ELEM(1, elem)
 
 
// Composite groups of types.
#define VT_BUILTIN_NUMERIC_VALUE_TYPES \
VT_INTEGRAL_BUILTIN_VALUE_TYPES VT_FLOATING_POINT_BUILTIN_VALUE_TYPES \
VT_TIMECODE_VALUE_TYPES
 
#define VT_BUILTIN_VALUE_TYPES \
VT_BUILTIN_NUMERIC_VALUE_TYPES VT_STRING_VALUE_TYPES
 
#define VT_SCALAR_CLASS_VALUE_TYPES \
VT_VEC_VALUE_TYPES \
VT_MATRIX_VALUE_TYPES \
VT_RANGE_VALUE_TYPES \
VT_QUATERNION_VALUE_TYPES \
VT_DUALQUATERNION_VALUE_TYPES
 
#define VT_SCALAR_VALUE_TYPES \
VT_BUILTIN_VALUE_TYPES VT_SCALAR_CLASS_VALUE_TYPES
 
// The following preprocessor code produces type aliases for VtArray holding
// various scalar value types.  The produced aliases are of the form:
//
// using VtIntArray = VtArray<int>;
// using VtDoubleArray = VtArray<double>;
template<typename T> class VtArray;
#define VT_ARRAY_ALIAS(unused, elem) \
using TF_PP_CAT( \
   Vt, TF_PP_CAT(VT_TYPE_NAME(elem), Array)) = VtArray< VT_TYPE(elem) >;
TF_PP_SEQ_FOR_EACH(VT_ARRAY_ALIAS, ~, VT_SCALAR_VALUE_TYPES)
 
// The following preprocessor code produces type aliases for VtArrayEdit holding
// various scalar value types.  The produced aliases are of the form:
//
// using VtIntArrayEdit = VtArrayEdit<int>;
// using VtDoubleArrayEdit = VtArrayEdit<double>;
template<typename T> class VtArrayEdit;
#define VT_ARRAY_EDIT_ALIAS(unused, elem) \
using TF_PP_CAT(Vt, TF_PP_CAT(VT_TYPE_NAME(elem), ArrayEdit)) \
    = VtArrayEdit< VT_TYPE(elem) >;
TF_PP_SEQ_FOR_EACH(VT_ARRAY_EDIT_ALIAS, ~, VT_SCALAR_VALUE_TYPES)
 
// The following preprocessor code produces type aliases for VtArrayEditBuilder
// holding various scalar value types.  The produced aliases are of the form:
//
// using VtIntArrayEditBuilder = VtArrayEditBuilder<int>;
// using VtDoubleArrayEditBuilder = VtArrayEditBuilder<double>;
template<typename T> class VtArrayEditBuilder;
#define VT_ARRAY_EDIT_BUILDER_ALIAS(unused, elem) \
using TF_PP_CAT(Vt, TF_PP_CAT(VT_TYPE_NAME(elem), ArrayEditBuilder)) \
    = VtArrayEditBuilder< VT_TYPE(elem) >;
TF_PP_SEQ_FOR_EACH(VT_ARRAY_EDIT_BUILDER_ALIAS, ~, VT_SCALAR_VALUE_TYPES)
 
// The following preprocessor code generates the boost pp sequence for
// all array value types (VT_ARRAY_VALUE_TYPES)
#define VT_ARRAY_TYPE_TUPLE(unused, elem) \
(( TF_PP_CAT(Vt, TF_PP_CAT(VT_TYPE_NAME(elem), Array)) , \
   TF_PP_CAT(VT_TYPE_NAME(elem), Array) ))
#define VT_ARRAY_VALUE_TYPES \
TF_PP_SEQ_FOR_EACH(VT_ARRAY_TYPE_TUPLE, ~, VT_SCALAR_VALUE_TYPES)
 
// The following preprocessor code generates the boost pp sequence for
// all array edit value types (VT_ARRAY_EDIT_VALUE_TYPES)
#define VT_ARRAY_EDIT_TYPE_TUPLE(unused, elem) \
(( TF_PP_CAT(Vt, TF_PP_CAT(VT_TYPE_NAME(elem), ArrayEdit)) , \
   TF_PP_CAT(VT_TYPE_NAME(elem), ArrayEdit) ))
#define VT_ARRAY_EDIT_VALUE_TYPES \
TF_PP_SEQ_FOR_EACH(VT_ARRAY_EDIT_TYPE_TUPLE, ~, VT_SCALAR_VALUE_TYPES)
 
// This unfortunately must be two separate PP lists, otherwise we exceed the
// MSVC macro nesting depth.
#define VT_VALUE_TYPES_1                                \
    VT_BUILTIN_VALUE_TYPES VT_SCALAR_CLASS_VALUE_TYPES
#define VT_VALUE_TYPES_2                                \
    VT_ARRAY_VALUE_TYPES VT_ARRAY_EDIT_VALUE_TYPES VT_NONARRAY_VALUE_TYPES
 
// Expand _macro for each value type tuple in VT_VALUE_TYPES_{1,2}.  The _macro
// must have the same form as for TF_PP_SEQ_FOR_EACH, namely MACRO(unused,
// elem), where `unused` should be ignored and `elem` is the VT_VALUE_TYPES
// tuple element.
#define VT_FOR_EACH_VALUE_TYPE(_macro)              \
    TF_PP_SEQ_FOR_EACH(_macro, ~, VT_VALUE_TYPES_1) \
    TF_PP_SEQ_FOR_EACH(_macro, ~, VT_VALUE_TYPES_2)
 
// Populate a type list from the preprocessor sequence.  The type `void` is
// prepended to accommodate the comma-type expansion for the rest of the type
// list type and then dropped by TfMetaTail.
#define VT_COMMA_TYPE(unused, elem) , VT_TYPE(elem)
using Vt_ValueTypeList =
    TfMetaApply<TfMetaTail, TfMetaList<
        void VT_FOR_EACH_VALUE_TYPE(VT_COMMA_TYPE)>>;
#undef VT_COMMA_TYPE
 
namespace Vt_KnownValueTypeDetail
{
 
// Implement compile-time value type indexes.
// Base case -- unknown types get index -1.
template <typename T>
constexpr int
GetIndexImpl(TfMetaList<>) {
    return -1;
}
 
template <typename T, typename Typelist>
constexpr int
GetIndexImpl(Typelist) {
    if (std::is_same_v<T, TfMetaApply<TfMetaHead, Typelist>>) {
        return 0;
    }
    else if (const int indexOfTail =
             GetIndexImpl<T>(TfMetaApply<TfMetaTail, Typelist>{});
             indexOfTail >= 0) {
        return 1 + indexOfTail;
    }
    else {
        return -1;
    }
}
 
template <typename T>
constexpr int
GetIndex() {
    return GetIndexImpl<T>(Vt_ValueTypeList{});
}
 
} // Vt_KnownValueTypeDetail
 
// Total number of 'known' value types.
constexpr int
VtGetNumKnownValueTypes() {
    return TfMetaApply<TfMetaLength, Vt_ValueTypeList>::value;
}
 
template <class T>
constexpr int
VtGetKnownValueTypeIndex()
{
    constexpr int index = Vt_KnownValueTypeDetail::GetIndex<T>();
    static_assert(index != -1, "T is not one of the known VT_VALUE_TYPES.");
    return index;
}
 
template <class T>
constexpr bool
VtIsKnownValueType()
{
    return Vt_KnownValueTypeDetail::GetIndex<T>() != -1;
}
 
// XXX: Works around an MSVC bug where constexpr functions cannot be used as the
// condition in enable_if, fixed in MSVC 2022 version 14.33 1933 (version 17.3).
// https://developercommunity.visualstudio.com/t/function-template-has-already-been-defined-using-s/833543
template <class T>
struct VtIsKnownValueType_Workaround
{
    static const bool value = VtIsKnownValueType<T>();
};
 
// Generally, we want to allow clients to register value-type transforms for
// their own user-defined types.  Registering transforms for built-in (float,
// double, string) or low-level (GfVec, GfMatrix) types can lead to ODR
// violations (due to trait differences in different TUs) and added performance
// costs.  So we allow registering transforms for all the types not known to Vt.
// However there are a couple of low-level types known to Vt that are explicitly
// allowed to support registered transforms.  This private function captures
// this set of types.
template <class T>
constexpr bool
Vt_IsTypeAllowedToRegisterTransforms()
{
    return !VtIsKnownValueType<T>()
        || std::is_same_v<T, GfTimeCode>
        // || std::is_same_v<T, GfDuration>
        ; 
}
 
// None of the VT_VALUE_TYPES are value proxies.  We want to specialize these
// templates here, since otherwise the VtIsTypedValueProxy will require a
// complete type to check if it derives VtTypedValueProxyBase.
#define VT_SPECIALIZE_IS_VALUE_PROXY(unused, elem)                             \
    template <> struct                                                         \
    VtIsValueProxy< VT_TYPE(elem) > : std::false_type {};                      \
    template <> struct                                                         \
    VtIsTypedValueProxy< VT_TYPE(elem) > : std::false_type {};                 \
    template <> struct                                                         \
    VtIsErasedValueProxy< VT_TYPE(elem) > : std::false_type {};
VT_FOR_EACH_VALUE_TYPE(VT_SPECIALIZE_IS_VALUE_PROXY)
#undef VT_SPECIALIZE_IS_VALUE_PROXY
 
// Free functions to represent "zero" for various base types.  See
// specializations in Types.cpp
template<typename T>
T VtZero();
 
// Shape representation used in VtArray for legacy code.  This is not supported
// at the pxr level or in usd.  Shape is represented by a total size, plus sized
// dimensions other than the last.  The size of the last dimension is computed
// as totalSize / (product-of-other-dimensions).
struct Vt_ShapeData {
    unsigned int GetRank() const {
        return
            otherDims[0] == 0 ? 1 :
            otherDims[1] == 0 ? 2 :
            otherDims[2] == 0 ? 3 : 4;
    }
    bool operator==(Vt_ShapeData const &other) const {
        if (totalSize != other.totalSize)
            return false;
        unsigned int thisRank = GetRank(), otherRank = other.GetRank();
        if (thisRank != otherRank)
            return false;
        return std::equal(otherDims, otherDims + GetRank() - 1,
                          other.otherDims);
    }
    bool operator!=(Vt_ShapeData const &other) const {
        return !(*this == other);
    }
    void clear() {
        memset(this, 0, sizeof(*this));
    }
    static const int NumOtherDims = 3;
    size_t totalSize;
    unsigned int otherDims[NumOtherDims];
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif // PXR_BASE_VT_TYPES_H