Merge commit '0f6aab9da6fe982218a01f4a5b896e65fcced437' as 'third_party/flatbuffers'
This commit is contained in:
Siarhei Fedartsou
+1493
File diff suppressed because it is too large
Load Diff
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export 'src/builder.dart';
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export 'src/reference.dart';
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+676
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import 'dart:convert';
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import 'dart:typed_data';
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import 'types.dart';
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/// The main builder class for creation of a FlexBuffer.
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class Builder {
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final ByteData _buffer;
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List<_StackValue> _stack = [];
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List<_StackPointer> _stackPointers = [];
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int _offset = 0;
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bool _finished = false;
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final Map<String, _StackValue> _stringCache = {};
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final Map<String, _StackValue> _keyCache = {};
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final Map<_KeysHash, _StackValue> _keyVectorCache = {};
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final Map<int, _StackValue> _indirectIntCache = {};
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final Map<double, _StackValue> _indirectDoubleCache = {};
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/// Instantiate the builder if you intent to gradually build up the buffer by calling
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/// add... methods and calling [finish] to receive the resulting byte array.
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///
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/// The default size of internal buffer is set to 2048. Provide a different value in order to avoid buffer copies.
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Builder({int size = 2048}) : _buffer = ByteData(size);
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/// Use this method in order to turn an object into a FlexBuffer directly.
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///
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/// Use the manual instantiation of the [Builder] and gradual addition of values, if performance is more important than convenience.
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static ByteBuffer buildFromObject(Object? value) {
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final builder = Builder();
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builder._add(value);
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final buffer = builder.finish();
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final byteData = ByteData(buffer.lengthInBytes);
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byteData.buffer.asUint8List().setAll(0, buffer);
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return byteData.buffer;
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}
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void _add(Object? value) {
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if (value == null) {
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addNull();
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} else if (value is bool) {
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addBool(value);
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} else if (value is int) {
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addInt(value);
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} else if (value is double) {
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addDouble(value);
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} else if (value is ByteBuffer) {
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addBlob(value);
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} else if (value is String) {
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addString(value);
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} else if (value is List<dynamic>) {
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startVector();
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for (var i = 0; i < value.length; i++) {
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_add(value[i]);
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}
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end();
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} else if (value is Map<String, dynamic>) {
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startMap();
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value.forEach((key, value) {
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addKey(key);
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_add(value);
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});
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end();
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} else {
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throw UnsupportedError('Value of unexpected type: $value');
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}
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}
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/// Use this method if you want to store a null value.
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///
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/// Specifically useful when building up a vector where values can be null.
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void addNull() {
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_integrityCheckOnValueAddition();
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_stack.add(_StackValue.withNull());
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}
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/// Adds a string value.
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void addInt(int value) {
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_integrityCheckOnValueAddition();
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_stack.add(_StackValue.withInt(value));
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}
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/// Adds a bool value.
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void addBool(bool value) {
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_integrityCheckOnValueAddition();
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_stack.add(_StackValue.withBool(value));
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}
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/// Adds a double value.
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void addDouble(double value) {
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_integrityCheckOnValueAddition();
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_stack.add(_StackValue.withDouble(value));
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}
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/// Adds a string value.
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void addString(String value) {
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_integrityCheckOnValueAddition();
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if (_stringCache.containsKey(value)) {
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_stack.add(_stringCache[value]!);
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return;
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}
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final utf8String = utf8.encode(value);
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final length = utf8String.length;
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final bitWidth = BitWidthUtil.uwidth(length);
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final byteWidth = _align(bitWidth);
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_writeUInt(length, byteWidth);
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final stringOffset = _offset;
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final newOffset = _newOffset(length + 1);
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_pushBuffer(utf8String);
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_offset = newOffset;
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final stackValue =
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_StackValue.withOffset(stringOffset, ValueType.String, bitWidth);
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_stack.add(stackValue);
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_stringCache[value] = stackValue;
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}
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/// This methods adds a key to a map and should be followed by an add... value call.
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///
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/// It also implies that you call this method only after you called [startMap].
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void addKey(String value) {
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_integrityCheckOnKeyAddition();
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if (_keyCache.containsKey(value)) {
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_stack.add(_keyCache[value]!);
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return;
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}
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final utf8String = utf8.encode(value);
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final length = utf8String.length;
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final keyOffset = _offset;
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final newOffset = _newOffset(length + 1);
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_pushBuffer(utf8String);
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_offset = newOffset;
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final stackValue =
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_StackValue.withOffset(keyOffset, ValueType.Key, BitWidth.width8);
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_stack.add(stackValue);
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_keyCache[value] = stackValue;
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}
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/// Adds a byte array.
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///
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/// This method can be used to store any generic BLOB.
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void addBlob(ByteBuffer value) {
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_integrityCheckOnValueAddition();
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final length = value.lengthInBytes;
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final bitWidth = BitWidthUtil.uwidth(length);
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final byteWidth = _align(bitWidth);
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_writeUInt(length, byteWidth);
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final blobOffset = _offset;
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final newOffset = _newOffset(length);
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_pushBuffer(value.asUint8List());
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_offset = newOffset;
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final stackValue =
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_StackValue.withOffset(blobOffset, ValueType.Blob, bitWidth);
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_stack.add(stackValue);
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}
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/// Stores int value indirectly in the buffer.
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///
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/// Adding large integer values indirectly might be beneficial if those values suppose to be store in a vector together with small integer values.
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/// This is due to the fact that FlexBuffers will add padding to small integer values, if they are stored together with large integer values.
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/// When we add integer indirectly the vector of ints will contain not the value itself, but only the relative offset to the value.
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/// By setting the [cache] parameter to true, you make sure that the builder tracks added int value and performs deduplication.
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void addIntIndirectly(int value, {bool cache = false}) {
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_integrityCheckOnValueAddition();
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if (_indirectIntCache.containsKey(value)) {
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_stack.add(_indirectIntCache[value]!);
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return;
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}
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final stackValue = _StackValue.withInt(value);
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final byteWidth = _align(stackValue.width);
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final newOffset = _newOffset(byteWidth);
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final valueOffset = _offset;
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_pushBuffer(stackValue.asU8List(stackValue.width));
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final stackOffset = _StackValue.withOffset(
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valueOffset, ValueType.IndirectInt, stackValue.width);
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_stack.add(stackOffset);
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_offset = newOffset;
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if (cache) {
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_indirectIntCache[value] = stackOffset;
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}
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}
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/// Stores double value indirectly in the buffer.
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///
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/// Double are stored as 8 or 4 byte values in FlexBuffers. If they are stored in a mixed vector, values which are smaller than 4 / 8 bytes will be padded.
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/// When we add double indirectly, the vector will contain not the value itself, but only the relative offset to the value. Which could occupy only 1 or 2 bytes, reducing the odds for unnecessary padding.
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/// By setting the [cache] parameter to true, you make sure that the builder tracks already added double value and performs deduplication.
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void addDoubleIndirectly(double value, {bool cache = false}) {
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_integrityCheckOnValueAddition();
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if (cache && _indirectDoubleCache.containsKey(value)) {
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_stack.add(_indirectDoubleCache[value]!);
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return;
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}
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final stackValue = _StackValue.withDouble(value);
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final byteWidth = _align(stackValue.width);
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final newOffset = _newOffset(byteWidth);
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final valueOffset = _offset;
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_pushBuffer(stackValue.asU8List(stackValue.width));
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final stackOffset = _StackValue.withOffset(
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valueOffset, ValueType.IndirectFloat, stackValue.width);
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_stack.add(stackOffset);
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_offset = newOffset;
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if (cache) {
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_indirectDoubleCache[value] = stackOffset;
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}
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}
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/// This method starts a vector definition and needs to be followed by 0 to n add... value calls.
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///
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/// The vector definition needs to be finished with an [end] call.
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/// It is also possible to add nested vector or map by calling [startVector] / [startMap].
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void startVector() {
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_integrityCheckOnValueAddition();
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_stackPointers.add(_StackPointer(_stack.length, true));
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}
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/// This method starts a map definition.
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///
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/// This method call needs to be followed by 0 to n [addKey] + add... value calls.
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/// The map definition needs to be finished with an [end] call.
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/// It is also possible to add nested vector or map by calling [startVector] / [startMap] after calling [addKey].
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void startMap() {
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_integrityCheckOnValueAddition();
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_stackPointers.add(_StackPointer(_stack.length, false));
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}
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/// Marks that the addition of values to the last vector, or map have ended.
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void end() {
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final pointer = _stackPointers.removeLast();
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if (pointer.isVector) {
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_endVector(pointer);
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} else {
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_sortKeysAndEndMap(pointer);
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}
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}
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/// Finish building the FlatBuffer and return array of bytes.
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///
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/// Can be called multiple times, to get the array of bytes.
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/// After the first call, adding values, or starting vectors / maps will result in an exception.
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Uint8List finish() {
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if (_finished == false) {
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_finish();
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}
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return _buffer.buffer.asUint8List(0, _offset);
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}
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/// Builds a FlatBuffer with current state without finishing the builder.
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///
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/// Creates an internal temporary copy of current builder and finishes the copy.
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/// Use this method, when the state of a long lasting builder need to be persisted periodically.
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ByteBuffer snapshot() {
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final tmp = Builder(size: _offset + 200);
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tmp._offset = _offset;
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tmp._stack = List.from(_stack);
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tmp._stackPointers = List.from(_stackPointers);
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tmp._buffer.buffer
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.asUint8List()
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.setAll(0, _buffer.buffer.asUint8List(0, _offset));
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for (var i = 0; i < tmp._stackPointers.length; i++) {
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tmp.end();
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}
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final buffer = tmp.finish();
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final bd = ByteData(buffer.lengthInBytes);
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bd.buffer.asUint8List().setAll(0, buffer);
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return bd.buffer;
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}
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void _integrityCheckOnValueAddition() {
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if (_finished) {
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throw StateError('Adding values after finish is prohibited');
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}
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if (_stackPointers.isNotEmpty && _stackPointers.last.isVector == false) {
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if (_stack.last.type != ValueType.Key) {
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throw StateError(
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'Adding value to a map before adding a key is prohibited');
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}
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}
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}
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void _integrityCheckOnKeyAddition() {
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if (_finished) {
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throw StateError('Adding values after finish is prohibited');
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}
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if (_stackPointers.isEmpty || _stackPointers.last.isVector) {
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throw StateError('Adding key before staring a map is prohibited');
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}
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}
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void _finish() {
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if (_stack.length != 1) {
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throw StateError(
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'Stack has to be exactly 1, but is ${_stack.length}. You have to end all started vectors and maps, before calling [finish]');
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}
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final value = _stack[0];
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final byteWidth = _align(value.elementWidth(_offset, 0));
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_writeStackValue(value, byteWidth);
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_writeUInt(value.storedPackedType(), 1);
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_writeUInt(byteWidth, 1);
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_finished = true;
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}
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_StackValue _createVector(int start, int vecLength, int step,
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[_StackValue? keys]) {
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var bitWidth = BitWidthUtil.uwidth(vecLength);
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var prefixElements = 1;
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if (keys != null) {
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var elemWidth = keys.elementWidth(_offset, 0);
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if (elemWidth.index > bitWidth.index) {
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bitWidth = elemWidth;
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}
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prefixElements += 2;
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}
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var vectorType = ValueType.Key;
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var typed = keys == null;
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for (var i = start; i < _stack.length; i += step) {
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final elemWidth = _stack[i].elementWidth(_offset, i + prefixElements);
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if (elemWidth.index > bitWidth.index) {
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bitWidth = elemWidth;
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}
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if (i == start) {
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vectorType = _stack[i].type;
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typed &= ValueTypeUtils.isTypedVectorElement(vectorType);
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} else {
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if (vectorType != _stack[i].type) {
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typed = false;
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}
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}
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}
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final byteWidth = _align(bitWidth);
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final fix = typed & ValueTypeUtils.isNumber(vectorType) &&
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vecLength >= 2 &&
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vecLength <= 4;
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if (keys != null) {
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_writeStackValue(keys, byteWidth);
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_writeUInt(1 << keys.width.index, byteWidth);
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}
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if (fix == false) {
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_writeUInt(vecLength, byteWidth);
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}
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final vecOffset = _offset;
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for (var i = start; i < _stack.length; i += step) {
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_writeStackValue(_stack[i], byteWidth);
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}
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if (typed == false) {
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for (var i = start; i < _stack.length; i += step) {
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_writeUInt(_stack[i].storedPackedType(), 1);
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}
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}
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if (keys != null) {
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return _StackValue.withOffset(vecOffset, ValueType.Map, bitWidth);
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}
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if (typed) {
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final vType =
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ValueTypeUtils.toTypedVector(vectorType, fix ? vecLength : 0);
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return _StackValue.withOffset(vecOffset, vType, bitWidth);
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}
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return _StackValue.withOffset(vecOffset, ValueType.Vector, bitWidth);
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}
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void _endVector(_StackPointer pointer) {
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final vecLength = _stack.length - pointer.stackPosition;
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final vec = _createVector(pointer.stackPosition, vecLength, 1);
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_stack.removeRange(pointer.stackPosition, _stack.length);
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_stack.add(vec);
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}
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||||
|
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void _sortKeysAndEndMap(_StackPointer pointer) {
|
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if (((_stack.length - pointer.stackPosition) & 1) == 1) {
|
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throw StateError(
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'The stack needs to hold key value pairs (even number of elements). Check if you combined [addKey] with add... method calls properly.');
|
||||
}
|
||||
|
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var sorted = true;
|
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for (var i = pointer.stackPosition; i < _stack.length - 2; i += 2) {
|
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if (_shouldFlip(_stack[i], _stack[i + 2])) {
|
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sorted = false;
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break;
|
||||
}
|
||||
}
|
||||
|
||||
if (sorted == false) {
|
||||
for (var i = pointer.stackPosition; i < _stack.length; i += 2) {
|
||||
var flipIndex = i;
|
||||
for (var j = i + 2; j < _stack.length; j += 2) {
|
||||
if (_shouldFlip(_stack[flipIndex], _stack[j])) {
|
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flipIndex = j;
|
||||
}
|
||||
}
|
||||
if (flipIndex != i) {
|
||||
var k = _stack[flipIndex];
|
||||
var v = _stack[flipIndex + 1];
|
||||
_stack[flipIndex] = _stack[i];
|
||||
_stack[flipIndex + 1] = _stack[i + 1];
|
||||
_stack[i] = k;
|
||||
_stack[i + 1] = v;
|
||||
}
|
||||
}
|
||||
}
|
||||
_endMap(pointer);
|
||||
}
|
||||
|
||||
void _endMap(_StackPointer pointer) {
|
||||
final vecLength = (_stack.length - pointer.stackPosition) >> 1;
|
||||
final offsets = <int>[];
|
||||
for (var i = pointer.stackPosition; i < _stack.length; i += 2) {
|
||||
offsets.add(_stack[i].offset!);
|
||||
}
|
||||
final keysHash = _KeysHash(offsets);
|
||||
_StackValue? keysStackValue;
|
||||
if (_keyVectorCache.containsKey(keysHash)) {
|
||||
keysStackValue = _keyVectorCache[keysHash];
|
||||
} else {
|
||||
keysStackValue = _createVector(pointer.stackPosition, vecLength, 2);
|
||||
_keyVectorCache[keysHash] = keysStackValue;
|
||||
}
|
||||
final vec =
|
||||
_createVector(pointer.stackPosition + 1, vecLength, 2, keysStackValue);
|
||||
_stack.removeRange(pointer.stackPosition, _stack.length);
|
||||
_stack.add(vec);
|
||||
}
|
||||
|
||||
bool _shouldFlip(_StackValue v1, _StackValue v2) {
|
||||
if (v1.type != ValueType.Key || v2.type != ValueType.Key) {
|
||||
throw StateError(
|
||||
'Stack values are not keys $v1 | $v2. Check if you combined [addKey] with add... method calls properly.');
|
||||
}
|
||||
|
||||
late int c1, c2;
|
||||
var index = 0;
|
||||
do {
|
||||
c1 = _buffer.getUint8(v1.offset! + index);
|
||||
c2 = _buffer.getUint8(v2.offset! + index);
|
||||
if (c2 < c1) return true;
|
||||
if (c1 < c2) return false;
|
||||
index += 1;
|
||||
} while (c1 != 0 && c2 != 0);
|
||||
return false;
|
||||
}
|
||||
|
||||
int _align(BitWidth width) {
|
||||
final byteWidth = BitWidthUtil.toByteWidth(width);
|
||||
_offset += BitWidthUtil.paddingSize(_offset, byteWidth);
|
||||
return byteWidth;
|
||||
}
|
||||
|
||||
void _writeStackValue(_StackValue value, int byteWidth) {
|
||||
final newOffset = _newOffset(byteWidth);
|
||||
if (value.isOffset) {
|
||||
final relativeOffset = _offset - value.offset!;
|
||||
if (byteWidth == 8 || relativeOffset < (1 << (byteWidth * 8))) {
|
||||
_writeUInt(relativeOffset, byteWidth);
|
||||
} else {
|
||||
throw StateError(
|
||||
'Unexpected size $byteWidth. This might be a bug. Please create an issue https://github.com/google/flatbuffers/issues/new');
|
||||
}
|
||||
} else {
|
||||
_pushBuffer(value.asU8List(BitWidthUtil.fromByteWidth(byteWidth)));
|
||||
}
|
||||
_offset = newOffset;
|
||||
}
|
||||
|
||||
void _writeUInt(int value, int byteWidth) {
|
||||
final newOffset = _newOffset(byteWidth);
|
||||
_pushUInt(value, BitWidthUtil.fromByteWidth(byteWidth));
|
||||
_offset = newOffset;
|
||||
}
|
||||
|
||||
int _newOffset(int newValueSize) {
|
||||
final newOffset = _offset + newValueSize;
|
||||
var size = _buffer.lengthInBytes;
|
||||
final prevSize = size;
|
||||
while (size < newOffset) {
|
||||
size <<= 1;
|
||||
}
|
||||
if (prevSize < size) {
|
||||
final newBuf = ByteData(size);
|
||||
newBuf.buffer.asUint8List().setAll(0, _buffer.buffer.asUint8List());
|
||||
}
|
||||
return newOffset;
|
||||
}
|
||||
|
||||
void _pushInt(int value, BitWidth width) {
|
||||
switch (width) {
|
||||
case BitWidth.width8:
|
||||
_buffer.setInt8(_offset, value);
|
||||
break;
|
||||
case BitWidth.width16:
|
||||
_buffer.setInt16(_offset, value, Endian.little);
|
||||
break;
|
||||
case BitWidth.width32:
|
||||
_buffer.setInt32(_offset, value, Endian.little);
|
||||
break;
|
||||
case BitWidth.width64:
|
||||
_buffer.setInt64(_offset, value, Endian.little);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
void _pushUInt(int value, BitWidth width) {
|
||||
switch (width) {
|
||||
case BitWidth.width8:
|
||||
_buffer.setUint8(_offset, value);
|
||||
break;
|
||||
case BitWidth.width16:
|
||||
_buffer.setUint16(_offset, value, Endian.little);
|
||||
break;
|
||||
case BitWidth.width32:
|
||||
_buffer.setUint32(_offset, value, Endian.little);
|
||||
break;
|
||||
case BitWidth.width64:
|
||||
_buffer.setUint64(_offset, value, Endian.little);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
void _pushBuffer(List<int> value) {
|
||||
_buffer.buffer.asUint8List().setAll(_offset, value);
|
||||
}
|
||||
}
|
||||
|
||||
class _StackValue {
|
||||
late Object _value;
|
||||
int? _offset;
|
||||
final ValueType _type;
|
||||
final BitWidth _width;
|
||||
|
||||
_StackValue.withNull()
|
||||
: _type = ValueType.Null,
|
||||
_width = BitWidth.width8;
|
||||
|
||||
_StackValue.withInt(int value)
|
||||
: _type = ValueType.Int,
|
||||
_width = BitWidthUtil.width(value),
|
||||
_value = value;
|
||||
|
||||
_StackValue.withBool(bool value)
|
||||
: _type = ValueType.Bool,
|
||||
_width = BitWidth.width8,
|
||||
_value = value;
|
||||
|
||||
_StackValue.withDouble(double value)
|
||||
: _type = ValueType.Float,
|
||||
_width = BitWidthUtil.width(value),
|
||||
_value = value;
|
||||
|
||||
_StackValue.withOffset(int value, ValueType type, BitWidth width)
|
||||
: _offset = value,
|
||||
_type = type,
|
||||
_width = width;
|
||||
|
||||
BitWidth storedWidth({BitWidth width = BitWidth.width8}) {
|
||||
return ValueTypeUtils.isInline(_type)
|
||||
? BitWidthUtil.max(_width, width)
|
||||
: _width;
|
||||
}
|
||||
|
||||
int storedPackedType({BitWidth width = BitWidth.width8}) {
|
||||
return ValueTypeUtils.packedType(_type, storedWidth(width: width));
|
||||
}
|
||||
|
||||
BitWidth elementWidth(int size, int index) {
|
||||
if (ValueTypeUtils.isInline(_type)) return _width;
|
||||
final offset = _offset!;
|
||||
for (var i = 0; i < 4; i++) {
|
||||
final width = 1 << i;
|
||||
final bitWidth = BitWidthUtil.uwidth(size +
|
||||
BitWidthUtil.paddingSize(size, width) +
|
||||
index * width -
|
||||
offset);
|
||||
if (1 << bitWidth.index == width) {
|
||||
return bitWidth;
|
||||
}
|
||||
}
|
||||
throw StateError(
|
||||
'Element is of unknown. Size: $size at index: $index. This might be a bug. Please create an issue https://github.com/google/flatbuffers/issues/new');
|
||||
}
|
||||
|
||||
List<int> asU8List(BitWidth width) {
|
||||
if (ValueTypeUtils.isNumber(_type)) {
|
||||
if (_type == ValueType.Float) {
|
||||
if (width == BitWidth.width32) {
|
||||
final result = ByteData(4);
|
||||
result.setFloat32(0, _value as double, Endian.little);
|
||||
return result.buffer.asUint8List();
|
||||
} else {
|
||||
final result = ByteData(8);
|
||||
result.setFloat64(0, _value as double, Endian.little);
|
||||
return result.buffer.asUint8List();
|
||||
}
|
||||
} else {
|
||||
switch (width) {
|
||||
case BitWidth.width8:
|
||||
final result = ByteData(1);
|
||||
result.setInt8(0, _value as int);
|
||||
return result.buffer.asUint8List();
|
||||
case BitWidth.width16:
|
||||
final result = ByteData(2);
|
||||
result.setInt16(0, _value as int, Endian.little);
|
||||
return result.buffer.asUint8List();
|
||||
case BitWidth.width32:
|
||||
final result = ByteData(4);
|
||||
result.setInt32(0, _value as int, Endian.little);
|
||||
return result.buffer.asUint8List();
|
||||
case BitWidth.width64:
|
||||
final result = ByteData(8);
|
||||
result.setInt64(0, _value as int, Endian.little);
|
||||
return result.buffer.asUint8List();
|
||||
}
|
||||
}
|
||||
}
|
||||
if (_type == ValueType.Null) {
|
||||
final result = ByteData(1);
|
||||
result.setInt8(0, 0);
|
||||
return result.buffer.asUint8List();
|
||||
}
|
||||
if (_type == ValueType.Bool) {
|
||||
final result = ByteData(1);
|
||||
result.setInt8(0, _value as bool ? 1 : 0);
|
||||
return result.buffer.asUint8List();
|
||||
}
|
||||
|
||||
throw StateError(
|
||||
'Unexpected type: $_type. This might be a bug. Please create an issue https://github.com/google/flatbuffers/issues/new');
|
||||
}
|
||||
|
||||
ValueType get type {
|
||||
return _type;
|
||||
}
|
||||
|
||||
BitWidth get width {
|
||||
return _width;
|
||||
}
|
||||
|
||||
bool get isOffset {
|
||||
return !ValueTypeUtils.isInline(_type);
|
||||
}
|
||||
|
||||
int? get offset => _offset;
|
||||
|
||||
bool get isFloat32 {
|
||||
return _type == ValueType.Float && _width == BitWidth.width32;
|
||||
}
|
||||
}
|
||||
|
||||
class _StackPointer {
|
||||
int stackPosition;
|
||||
bool isVector;
|
||||
|
||||
_StackPointer(this.stackPosition, this.isVector);
|
||||
}
|
||||
|
||||
class _KeysHash {
|
||||
final List<int> keys;
|
||||
|
||||
const _KeysHash(this.keys);
|
||||
|
||||
@override
|
||||
bool operator ==(Object other) {
|
||||
if (other is _KeysHash) {
|
||||
if (keys.length != other.keys.length) return false;
|
||||
for (var i = 0; i < keys.length; i++) {
|
||||
if (keys[i] != other.keys[i]) return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
@override
|
||||
int get hashCode {
|
||||
var result = 17;
|
||||
for (var i = 0; i < keys.length; i++) {
|
||||
result = result * 23 + keys[i];
|
||||
}
|
||||
return result;
|
||||
}
|
||||
}
|
||||
+481
@@ -0,0 +1,481 @@
|
||||
import 'dart:collection';
|
||||
import 'dart:convert';
|
||||
import 'dart:typed_data';
|
||||
import 'types.dart';
|
||||
|
||||
/// Main class to read a value out of a FlexBuffer.
|
||||
///
|
||||
/// This class let you access values stored in the buffer in a lazy fashion.
|
||||
class Reference {
|
||||
final ByteData _buffer;
|
||||
final int _offset;
|
||||
final BitWidth _parentWidth;
|
||||
final String _path;
|
||||
final int _byteWidth;
|
||||
final ValueType _valueType;
|
||||
int? _length;
|
||||
|
||||
Reference._(
|
||||
this._buffer, this._offset, this._parentWidth, int packedType, this._path,
|
||||
[int? byteWidth, ValueType? valueType])
|
||||
: _byteWidth = byteWidth ?? 1 << (packedType & 3),
|
||||
_valueType = valueType ?? ValueTypeUtils.fromInt(packedType >> 2);
|
||||
|
||||
/// Use this method to access the root value of a FlexBuffer.
|
||||
static Reference fromBuffer(ByteBuffer buffer) {
|
||||
final len = buffer.lengthInBytes;
|
||||
if (len < 3) {
|
||||
throw UnsupportedError('Buffer needs to be bigger than 3');
|
||||
}
|
||||
final byteData = ByteData.view(buffer);
|
||||
final byteWidth = byteData.getUint8(len - 1);
|
||||
final packedType = byteData.getUint8(len - 2);
|
||||
final offset = len - byteWidth - 2;
|
||||
return Reference._(ByteData.view(buffer), offset,
|
||||
BitWidthUtil.fromByteWidth(byteWidth), packedType, "/");
|
||||
}
|
||||
|
||||
/// Returns true if the underlying value is null.
|
||||
bool get isNull => _valueType == ValueType.Null;
|
||||
|
||||
/// Returns true if the underlying value can be represented as [num].
|
||||
bool get isNum =>
|
||||
ValueTypeUtils.isNumber(_valueType) ||
|
||||
ValueTypeUtils.isIndirectNumber(_valueType);
|
||||
|
||||
/// Returns true if the underlying value was encoded as a float (direct or indirect).
|
||||
bool get isDouble =>
|
||||
_valueType == ValueType.Float || _valueType == ValueType.IndirectFloat;
|
||||
|
||||
/// Returns true if the underlying value was encoded as an int or uint (direct or indirect).
|
||||
bool get isInt => isNum && !isDouble;
|
||||
|
||||
/// Returns true if the underlying value was encoded as a string or a key.
|
||||
bool get isString =>
|
||||
_valueType == ValueType.String || _valueType == ValueType.Key;
|
||||
|
||||
/// Returns true if the underlying value was encoded as a bool.
|
||||
bool get isBool => _valueType == ValueType.Bool;
|
||||
|
||||
/// Returns true if the underlying value was encoded as a blob.
|
||||
bool get isBlob => _valueType == ValueType.Blob;
|
||||
|
||||
/// Returns true if the underlying value points to a vector.
|
||||
bool get isVector => ValueTypeUtils.isAVector(_valueType);
|
||||
|
||||
/// Returns true if the underlying value points to a map.
|
||||
bool get isMap => _valueType == ValueType.Map;
|
||||
|
||||
/// If this [isBool], returns the bool value. Otherwise, returns null.
|
||||
bool? get boolValue {
|
||||
if (_valueType == ValueType.Bool) {
|
||||
return _readInt(_offset, _parentWidth) != 0;
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/// Returns an [int], if the underlying value can be represented as an int.
|
||||
///
|
||||
/// Otherwise returns [null].
|
||||
int? get intValue {
|
||||
if (_valueType == ValueType.Int) {
|
||||
return _readInt(_offset, _parentWidth);
|
||||
}
|
||||
if (_valueType == ValueType.UInt) {
|
||||
return _readUInt(_offset, _parentWidth);
|
||||
}
|
||||
if (_valueType == ValueType.IndirectInt) {
|
||||
return _readInt(_indirect, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
}
|
||||
if (_valueType == ValueType.IndirectUInt) {
|
||||
return _readUInt(_indirect, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/// Returns [double], if the underlying value [isDouble].
|
||||
///
|
||||
/// Otherwise returns [null].
|
||||
double? get doubleValue {
|
||||
if (_valueType == ValueType.Float) {
|
||||
return _readFloat(_offset, _parentWidth);
|
||||
}
|
||||
if (_valueType == ValueType.IndirectFloat) {
|
||||
return _readFloat(_indirect, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/// Returns [num], if the underlying value is numeric, be it int uint, or float (direct or indirect).
|
||||
///
|
||||
/// Otherwise returns [null].
|
||||
num? get numValue => doubleValue ?? intValue;
|
||||
|
||||
/// Returns [String] value or null otherwise.
|
||||
///
|
||||
/// This method performers a utf8 decoding, as FlexBuffers format stores strings in utf8 encoding.
|
||||
String? get stringValue {
|
||||
if (_valueType == ValueType.String || _valueType == ValueType.Key) {
|
||||
return utf8.decode(_buffer.buffer.asUint8List(_indirect, length));
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/// Returns [Uint8List] value or null otherwise.
|
||||
Uint8List? get blobValue {
|
||||
if (_valueType == ValueType.Blob) {
|
||||
return _buffer.buffer.asUint8List(_indirect, length);
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/// Can be used with an [int] or a [String] value for key.
|
||||
/// If the underlying value in FlexBuffer is a vector, then use [int] for access.
|
||||
/// If the underlying value in FlexBuffer is a map, then use [String] for access.
|
||||
/// Returns [Reference] value. Throws an exception when [key] is not applicable.
|
||||
Reference operator [](Object key) {
|
||||
if (key is int && ValueTypeUtils.isAVector(_valueType)) {
|
||||
final index = key;
|
||||
if (index >= length || index < 0) {
|
||||
throw ArgumentError(
|
||||
'Key: [$key] is not applicable on: $_path of: $_valueType length: $length');
|
||||
}
|
||||
final elementOffset = _indirect + index * _byteWidth;
|
||||
int packedType = 0;
|
||||
int? byteWidth;
|
||||
ValueType? valueType;
|
||||
if (ValueTypeUtils.isTypedVector(_valueType)) {
|
||||
byteWidth = 1;
|
||||
valueType = ValueTypeUtils.typedVectorElementType(_valueType);
|
||||
} else if (ValueTypeUtils.isFixedTypedVector(_valueType)) {
|
||||
byteWidth = 1;
|
||||
valueType = ValueTypeUtils.fixedTypedVectorElementType(_valueType);
|
||||
} else {
|
||||
packedType = _buffer.getUint8(_indirect + length * _byteWidth + index);
|
||||
}
|
||||
return Reference._(
|
||||
_buffer,
|
||||
elementOffset,
|
||||
BitWidthUtil.fromByteWidth(_byteWidth),
|
||||
packedType,
|
||||
"$_path[$index]",
|
||||
byteWidth,
|
||||
valueType);
|
||||
}
|
||||
if (key is String && _valueType == ValueType.Map) {
|
||||
final index = _keyIndex(key);
|
||||
if (index != null) {
|
||||
return _valueForIndexWithKey(index, key);
|
||||
}
|
||||
}
|
||||
throw ArgumentError(
|
||||
'Key: [$key] is not applicable on: $_path of: $_valueType');
|
||||
}
|
||||
|
||||
/// Get an iterable if the underlying flexBuffer value is a vector.
|
||||
/// Otherwise throws an exception.
|
||||
Iterable<Reference> get vectorIterable {
|
||||
if (isVector == false) {
|
||||
throw UnsupportedError('Value is not a vector. It is: $_valueType');
|
||||
}
|
||||
return _VectorIterator(this);
|
||||
}
|
||||
|
||||
/// Get an iterable for keys if the underlying flexBuffer value is a map.
|
||||
/// Otherwise throws an exception.
|
||||
Iterable<String> get mapKeyIterable {
|
||||
if (isMap == false) {
|
||||
throw UnsupportedError('Value is not a map. It is: $_valueType');
|
||||
}
|
||||
return _MapKeyIterator(this);
|
||||
}
|
||||
|
||||
/// Get an iterable for values if the underlying flexBuffer value is a map.
|
||||
/// Otherwise throws an exception.
|
||||
Iterable<Reference> get mapValueIterable {
|
||||
if (isMap == false) {
|
||||
throw UnsupportedError('Value is not a map. It is: $_valueType');
|
||||
}
|
||||
return _MapValueIterator(this);
|
||||
}
|
||||
|
||||
/// Returns the length of the underlying FlexBuffer value.
|
||||
/// If the underlying value is [null] the length is 0.
|
||||
/// If the underlying value is a number, or a bool, the length is 1.
|
||||
/// If the underlying value is a vector, or map, the length reflects number of elements / element pairs.
|
||||
/// If the values is a string or a blob, the length reflects a number of bytes the value occupies (strings are encoded in utf8 format).
|
||||
int get length {
|
||||
if (_length == null) {
|
||||
// needs to be checked before more generic isAVector
|
||||
if (ValueTypeUtils.isFixedTypedVector(_valueType)) {
|
||||
_length = ValueTypeUtils.fixedTypedVectorElementSize(_valueType);
|
||||
} else if (_valueType == ValueType.Blob ||
|
||||
ValueTypeUtils.isAVector(_valueType) ||
|
||||
_valueType == ValueType.Map) {
|
||||
_length = _readUInt(
|
||||
_indirect - _byteWidth, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
} else if (_valueType == ValueType.Null) {
|
||||
_length = 0;
|
||||
} else if (_valueType == ValueType.String) {
|
||||
final indirect = _indirect;
|
||||
var sizeByteWidth = _byteWidth;
|
||||
var size = _readUInt(indirect - sizeByteWidth,
|
||||
BitWidthUtil.fromByteWidth(sizeByteWidth));
|
||||
while (_buffer.getInt8(indirect + size) != 0) {
|
||||
sizeByteWidth <<= 1;
|
||||
size = _readUInt(indirect - sizeByteWidth,
|
||||
BitWidthUtil.fromByteWidth(sizeByteWidth));
|
||||
}
|
||||
_length = size;
|
||||
} else if (_valueType == ValueType.Key) {
|
||||
final indirect = _indirect;
|
||||
var size = 1;
|
||||
while (_buffer.getInt8(indirect + size) != 0) {
|
||||
size += 1;
|
||||
}
|
||||
_length = size;
|
||||
} else {
|
||||
_length = 1;
|
||||
}
|
||||
}
|
||||
return _length!;
|
||||
}
|
||||
|
||||
/// Returns a minified JSON representation of the underlying FlexBuffer value.
|
||||
///
|
||||
/// This method involves materializing the entire object tree, which may be
|
||||
/// expensive. It is more efficient to work with [Reference] and access only the needed data.
|
||||
/// Blob values are represented as base64 encoded string.
|
||||
String get json {
|
||||
if (_valueType == ValueType.Bool) {
|
||||
return boolValue! ? 'true' : 'false';
|
||||
}
|
||||
if (_valueType == ValueType.Null) {
|
||||
return 'null';
|
||||
}
|
||||
if (ValueTypeUtils.isNumber(_valueType)) {
|
||||
return jsonEncode(numValue);
|
||||
}
|
||||
if (_valueType == ValueType.String) {
|
||||
return jsonEncode(stringValue);
|
||||
}
|
||||
if (_valueType == ValueType.Blob) {
|
||||
return jsonEncode(base64Encode(blobValue!));
|
||||
}
|
||||
if (ValueTypeUtils.isAVector(_valueType)) {
|
||||
final result = StringBuffer();
|
||||
result.write('[');
|
||||
for (var i = 0; i < length; i++) {
|
||||
result.write(this[i].json);
|
||||
if (i < length - 1) {
|
||||
result.write(',');
|
||||
}
|
||||
}
|
||||
result.write(']');
|
||||
return result.toString();
|
||||
}
|
||||
if (_valueType == ValueType.Map) {
|
||||
final result = StringBuffer();
|
||||
result.write('{');
|
||||
for (var i = 0; i < length; i++) {
|
||||
result.write(jsonEncode(_keyForIndex(i)));
|
||||
result.write(':');
|
||||
result.write(_valueForIndex(i).json);
|
||||
if (i < length - 1) {
|
||||
result.write(',');
|
||||
}
|
||||
}
|
||||
result.write('}');
|
||||
return result.toString();
|
||||
}
|
||||
throw UnsupportedError(
|
||||
'Type: $_valueType is not supported for JSON conversion');
|
||||
}
|
||||
|
||||
/// Computes the indirect offset of the value.
|
||||
///
|
||||
/// To optimize for the more common case of being called only once, this
|
||||
/// value is not cached. Callers that need to use it more than once should
|
||||
/// cache the return value in a local variable.
|
||||
int get _indirect {
|
||||
final step = _readUInt(_offset, _parentWidth);
|
||||
return _offset - step;
|
||||
}
|
||||
|
||||
int _readInt(int offset, BitWidth width) {
|
||||
_validateOffset(offset, width);
|
||||
if (width == BitWidth.width8) {
|
||||
return _buffer.getInt8(offset);
|
||||
}
|
||||
if (width == BitWidth.width16) {
|
||||
return _buffer.getInt16(offset, Endian.little);
|
||||
}
|
||||
if (width == BitWidth.width32) {
|
||||
return _buffer.getInt32(offset, Endian.little);
|
||||
}
|
||||
return _buffer.getInt64(offset, Endian.little);
|
||||
}
|
||||
|
||||
int _readUInt(int offset, BitWidth width) {
|
||||
_validateOffset(offset, width);
|
||||
if (width == BitWidth.width8) {
|
||||
return _buffer.getUint8(offset);
|
||||
}
|
||||
if (width == BitWidth.width16) {
|
||||
return _buffer.getUint16(offset, Endian.little);
|
||||
}
|
||||
if (width == BitWidth.width32) {
|
||||
return _buffer.getUint32(offset, Endian.little);
|
||||
}
|
||||
return _buffer.getUint64(offset, Endian.little);
|
||||
}
|
||||
|
||||
double _readFloat(int offset, BitWidth width) {
|
||||
_validateOffset(offset, width);
|
||||
if (width.index < BitWidth.width32.index) {
|
||||
throw StateError('Bad width: $width');
|
||||
}
|
||||
|
||||
if (width == BitWidth.width32) {
|
||||
return _buffer.getFloat32(offset, Endian.little);
|
||||
}
|
||||
|
||||
return _buffer.getFloat64(offset, Endian.little);
|
||||
}
|
||||
|
||||
void _validateOffset(int offset, BitWidth width) {
|
||||
if (_offset < 0 ||
|
||||
_buffer.lengthInBytes <= offset + width.index ||
|
||||
offset & (BitWidthUtil.toByteWidth(width) - 1) != 0) {
|
||||
throw StateError('Bad offset: $offset, width: $width');
|
||||
}
|
||||
}
|
||||
|
||||
int? _keyIndex(String key) {
|
||||
final input = utf8.encode(key);
|
||||
final keysVectorOffset = _indirect - _byteWidth * 3;
|
||||
final indirectOffset = keysVectorOffset -
|
||||
_readUInt(keysVectorOffset, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
final byteWidth = _readUInt(
|
||||
keysVectorOffset + _byteWidth, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
var low = 0;
|
||||
var high = length - 1;
|
||||
while (low <= high) {
|
||||
final mid = (high + low) >> 1;
|
||||
final dif = _diffKeys(input, mid, indirectOffset, byteWidth);
|
||||
if (dif == 0) return mid;
|
||||
if (dif < 0) {
|
||||
high = mid - 1;
|
||||
} else {
|
||||
low = mid + 1;
|
||||
}
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
int _diffKeys(List<int> input, int index, int indirectOffset, int byteWidth) {
|
||||
final keyOffset = indirectOffset + index * byteWidth;
|
||||
final keyIndirectOffset =
|
||||
keyOffset - _readUInt(keyOffset, BitWidthUtil.fromByteWidth(byteWidth));
|
||||
for (var i = 0; i < input.length; i++) {
|
||||
final dif = input[i] - _buffer.getUint8(keyIndirectOffset + i);
|
||||
if (dif != 0) {
|
||||
return dif;
|
||||
}
|
||||
}
|
||||
return (_buffer.getUint8(keyIndirectOffset + input.length) == 0) ? 0 : -1;
|
||||
}
|
||||
|
||||
Reference _valueForIndexWithKey(int index, String key) {
|
||||
final indirect = _indirect;
|
||||
final elementOffset = indirect + index * _byteWidth;
|
||||
final packedType = _buffer.getUint8(indirect + length * _byteWidth + index);
|
||||
return Reference._(_buffer, elementOffset,
|
||||
BitWidthUtil.fromByteWidth(_byteWidth), packedType, "$_path/$key");
|
||||
}
|
||||
|
||||
Reference _valueForIndex(int index) {
|
||||
final indirect = _indirect;
|
||||
final elementOffset = indirect + index * _byteWidth;
|
||||
final packedType = _buffer.getUint8(indirect + length * _byteWidth + index);
|
||||
return Reference._(_buffer, elementOffset,
|
||||
BitWidthUtil.fromByteWidth(_byteWidth), packedType, "$_path/[$index]");
|
||||
}
|
||||
|
||||
String _keyForIndex(int index) {
|
||||
final keysVectorOffset = _indirect - _byteWidth * 3;
|
||||
final indirectOffset = keysVectorOffset -
|
||||
_readUInt(keysVectorOffset, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
final byteWidth = _readUInt(
|
||||
keysVectorOffset + _byteWidth, BitWidthUtil.fromByteWidth(_byteWidth));
|
||||
final keyOffset = indirectOffset + index * byteWidth;
|
||||
final keyIndirectOffset =
|
||||
keyOffset - _readUInt(keyOffset, BitWidthUtil.fromByteWidth(byteWidth));
|
||||
var length = 0;
|
||||
while (_buffer.getUint8(keyIndirectOffset + length) != 0) {
|
||||
length += 1;
|
||||
}
|
||||
return utf8.decode(_buffer.buffer.asUint8List(keyIndirectOffset, length));
|
||||
}
|
||||
}
|
||||
|
||||
class _VectorIterator
|
||||
with IterableMixin<Reference>
|
||||
implements Iterator<Reference> {
|
||||
final Reference _vector;
|
||||
int index = -1;
|
||||
|
||||
_VectorIterator(this._vector);
|
||||
|
||||
@override
|
||||
Reference get current => _vector[index];
|
||||
|
||||
@override
|
||||
bool moveNext() {
|
||||
index++;
|
||||
return index < _vector.length;
|
||||
}
|
||||
|
||||
@override
|
||||
Iterator<Reference> get iterator => this;
|
||||
}
|
||||
|
||||
class _MapKeyIterator with IterableMixin<String> implements Iterator<String> {
|
||||
final Reference _map;
|
||||
int index = -1;
|
||||
|
||||
_MapKeyIterator(this._map);
|
||||
|
||||
@override
|
||||
String get current => _map._keyForIndex(index);
|
||||
|
||||
@override
|
||||
bool moveNext() {
|
||||
index++;
|
||||
return index < _map.length;
|
||||
}
|
||||
|
||||
@override
|
||||
Iterator<String> get iterator => this;
|
||||
}
|
||||
|
||||
class _MapValueIterator
|
||||
with IterableMixin<Reference>
|
||||
implements Iterator<Reference> {
|
||||
final Reference _map;
|
||||
int index = -1;
|
||||
|
||||
_MapValueIterator(this._map);
|
||||
|
||||
@override
|
||||
Reference get current => _map._valueForIndex(index);
|
||||
|
||||
@override
|
||||
bool moveNext() {
|
||||
index++;
|
||||
return index < _map.length;
|
||||
}
|
||||
|
||||
@override
|
||||
Iterator<Reference> get iterator => this;
|
||||
}
|
||||
+190
@@ -0,0 +1,190 @@
|
||||
import 'dart:typed_data';
|
||||
|
||||
/// Represents the number of bits a value occupies.
|
||||
enum BitWidth { width8, width16, width32, width64 }
|
||||
|
||||
class BitWidthUtil {
|
||||
static int toByteWidth(BitWidth self) {
|
||||
return 1 << self.index;
|
||||
}
|
||||
|
||||
static BitWidth width(num value) {
|
||||
if (value is int) {
|
||||
var v = value.toInt().abs();
|
||||
if (v >> 7 == 0) return BitWidth.width8;
|
||||
if (v >> 15 == 0) return BitWidth.width16;
|
||||
if (v >> 31 == 0) return BitWidth.width32;
|
||||
return BitWidth.width64;
|
||||
}
|
||||
return value == _toF32(value as double)
|
||||
? BitWidth.width32
|
||||
: BitWidth.width64;
|
||||
}
|
||||
|
||||
static BitWidth uwidth(num value) {
|
||||
if (value.toInt() == value) {
|
||||
var v = value.toInt().abs();
|
||||
if (v >> 8 == 0) return BitWidth.width8;
|
||||
if (v >> 16 == 0) return BitWidth.width16;
|
||||
if (v >> 32 == 0) return BitWidth.width32;
|
||||
return BitWidth.width64;
|
||||
}
|
||||
return value == _toF32(value as double)
|
||||
? BitWidth.width32
|
||||
: BitWidth.width64;
|
||||
}
|
||||
|
||||
static BitWidth fromByteWidth(int value) {
|
||||
if (value == 1) {
|
||||
return BitWidth.width8;
|
||||
}
|
||||
if (value == 2) {
|
||||
return BitWidth.width16;
|
||||
}
|
||||
if (value == 4) {
|
||||
return BitWidth.width32;
|
||||
}
|
||||
if (value == 8) {
|
||||
return BitWidth.width64;
|
||||
}
|
||||
throw Exception('Unexpected value $value');
|
||||
}
|
||||
|
||||
static int paddingSize(int bufSize, int scalarSize) {
|
||||
return (~bufSize + 1) & (scalarSize - 1);
|
||||
}
|
||||
|
||||
static double _toF32(double value) {
|
||||
var bdata = ByteData(4);
|
||||
bdata.setFloat32(0, value);
|
||||
return bdata.getFloat32(0);
|
||||
}
|
||||
|
||||
static BitWidth max(BitWidth self, BitWidth other) {
|
||||
if (self.index < other.index) {
|
||||
return other;
|
||||
}
|
||||
return self;
|
||||
}
|
||||
}
|
||||
|
||||
/// Represents all internal FlexBuffer types.
|
||||
enum ValueType {
|
||||
Null,
|
||||
Int,
|
||||
UInt,
|
||||
Float,
|
||||
Key,
|
||||
String,
|
||||
IndirectInt,
|
||||
IndirectUInt,
|
||||
IndirectFloat,
|
||||
Map,
|
||||
Vector,
|
||||
VectorInt,
|
||||
VectorUInt,
|
||||
VectorFloat,
|
||||
VectorKey,
|
||||
@Deprecated(
|
||||
'VectorString is deprecated due to a flaw in the binary format (https://github.com/google/flatbuffers/issues/5627)')
|
||||
VectorString,
|
||||
VectorInt2,
|
||||
VectorUInt2,
|
||||
VectorFloat2,
|
||||
VectorInt3,
|
||||
VectorUInt3,
|
||||
VectorFloat3,
|
||||
VectorInt4,
|
||||
VectorUInt4,
|
||||
VectorFloat4,
|
||||
Blob,
|
||||
Bool,
|
||||
VectorBool
|
||||
}
|
||||
|
||||
class ValueTypeUtils {
|
||||
static int toInt(ValueType self) {
|
||||
if (self == ValueType.VectorBool) return 36;
|
||||
return self.index;
|
||||
}
|
||||
|
||||
static ValueType fromInt(int value) {
|
||||
if (value == 36) return ValueType.VectorBool;
|
||||
return ValueType.values[value];
|
||||
}
|
||||
|
||||
static bool isInline(ValueType self) {
|
||||
return self == ValueType.Bool || toInt(self) <= toInt(ValueType.Float);
|
||||
}
|
||||
|
||||
static bool isNumber(ValueType self) {
|
||||
return toInt(self) >= toInt(ValueType.Int) &&
|
||||
toInt(self) <= toInt(ValueType.Float);
|
||||
}
|
||||
|
||||
static bool isIndirectNumber(ValueType self) {
|
||||
return toInt(self) >= toInt(ValueType.IndirectInt) &&
|
||||
toInt(self) <= toInt(ValueType.IndirectFloat);
|
||||
}
|
||||
|
||||
static bool isTypedVectorElement(ValueType self) {
|
||||
return self == ValueType.Bool ||
|
||||
(toInt(self) >= toInt(ValueType.Int) &&
|
||||
toInt(self) <= toInt(ValueType.String));
|
||||
}
|
||||
|
||||
static bool isTypedVector(ValueType self) {
|
||||
return self == ValueType.VectorBool ||
|
||||
(toInt(self) >= toInt(ValueType.VectorInt) &&
|
||||
toInt(self) <= toInt(ValueType.VectorString));
|
||||
}
|
||||
|
||||
static bool isFixedTypedVector(ValueType self) {
|
||||
return (toInt(self) >= toInt(ValueType.VectorInt2) &&
|
||||
toInt(self) <= toInt(ValueType.VectorFloat4));
|
||||
}
|
||||
|
||||
static bool isAVector(ValueType self) {
|
||||
return (isTypedVector(self) ||
|
||||
isFixedTypedVector(self) ||
|
||||
self == ValueType.Vector);
|
||||
}
|
||||
|
||||
static ValueType toTypedVector(ValueType self, int length) {
|
||||
if (length == 0) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
toInt(self) - toInt(ValueType.Int) + toInt(ValueType.VectorInt));
|
||||
}
|
||||
if (length == 2) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
toInt(self) - toInt(ValueType.Int) + toInt(ValueType.VectorInt2));
|
||||
}
|
||||
if (length == 3) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
toInt(self) - toInt(ValueType.Int) + toInt(ValueType.VectorInt3));
|
||||
}
|
||||
if (length == 4) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
toInt(self) - toInt(ValueType.Int) + toInt(ValueType.VectorInt4));
|
||||
}
|
||||
throw Exception('unexpected length ' + length.toString());
|
||||
}
|
||||
|
||||
static ValueType typedVectorElementType(ValueType self) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
toInt(self) - toInt(ValueType.VectorInt) + toInt(ValueType.Int));
|
||||
}
|
||||
|
||||
static ValueType fixedTypedVectorElementType(ValueType self) {
|
||||
return ValueTypeUtils.fromInt(
|
||||
(toInt(self) - toInt(ValueType.VectorInt2)) % 3 + toInt(ValueType.Int));
|
||||
}
|
||||
|
||||
static int fixedTypedVectorElementSize(ValueType self) {
|
||||
return (toInt(self) - toInt(ValueType.VectorInt2)) ~/ 3 + 2;
|
||||
}
|
||||
|
||||
static int packedType(ValueType self, BitWidth bitWidth) {
|
||||
return bitWidth.index | (toInt(self) << 2);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user