QScriptValue TypedArrayPrototype::subarray(qint32 begin) {
TypedArray* typedArray = static_cast<TypedArray*>(parent());
QScriptValue arrayBuffer = thisObject().data().property(typedArray->_bufferName);
qint32 byteOffset = thisObject().data().property(typedArray->_byteOffsetName).toInt32();
qint32 length = thisObject().data().property(typedArray->_lengthName).toInt32();
qint32 bytesPerElement = typedArray->_bytesPerElement;
// if indices < 0 then they start from the end of the array
begin = (begin < 0) ? length + begin : begin;
// here we clamp the indices to fit the array
begin = glm::clamp(begin, 0, (length - 1));
byteOffset += begin * bytesPerElement;
return typedArray->newInstance(arrayBuffer, byteOffset, length - begin);
}
QScriptValue TypedArrayPrototype::subarray(qint32 begin, qint32 end) {
TypedArray* typedArray = static_cast<TypedArray*>(parent());
QScriptValue arrayBuffer = thisObject().data().property(typedArray->_bufferName);
qint32 byteOffset = thisObject().data().property(typedArray->_byteOffsetName).toInt32();
qint32 length = thisObject().data().property(typedArray->_lengthName).toInt32();
qint32 bytesPerElement = typedArray->_bytesPerElement;
// if indices < 0 then they start from the end of the array
begin = (begin < 0) ? length + begin : begin;
end = (end < 0) ? length + end : end;
// here we clamp the indices to fit the array
// note: begin offset is *inclusive* while end offset is *exclusive*
// (see: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/subarray#Parameters)
begin = glm::clamp(begin, 0, (length - 1));
end = glm::clamp(end, 0, length);
byteOffset += begin * bytesPerElement;
length = (end - begin > 0) ? end - begin : 0;
return typedArray->newInstance(arrayBuffer, byteOffset, length);
}
QScriptValue TypedArray::construct(QScriptContext* context, QScriptEngine* engine) {
TypedArray* cls = qscriptvalue_cast<TypedArray*>(context->callee().data());
if (!cls) {
return QScriptValue();
}
if (context->argumentCount() == 0) {
return cls->newInstance(0);
}
QScriptValue newObject;
QScriptValue bufferArg = context->argument(0);
QByteArray* arrayBuffer = qscriptvalue_cast<QByteArray*>(bufferArg.data());
// parse arguments
if (arrayBuffer) {
if (context->argumentCount() == 1) {
// Case for entire ArrayBuffer
newObject = cls->newInstance(bufferArg, 0, arrayBuffer->size());
} else {
QScriptValue byteOffsetArg = context->argument(1);
if (!byteOffsetArg.isNumber()) {
engine->evaluate("throw \"ArgumentError: 2nd arg is not a number\"");
return QScriptValue();
}
if (byteOffsetArg.toInt32() < 0 || byteOffsetArg.toInt32() > arrayBuffer->size()) {
engine->evaluate("throw \"RangeError: byteOffset out of range\"");
return QScriptValue();
}
if (byteOffsetArg.toInt32() % cls->_bytesPerElement != 0) {
engine->evaluate("throw \"RangeError: byteOffset not a multiple of BYTES_PER_ELEMENT\"");
}
quint32 byteOffset = byteOffsetArg.toInt32();
if (context->argumentCount() == 2) {
// case for end of ArrayBuffer
if ((arrayBuffer->size() - byteOffset) % cls->_bytesPerElement != 0) {
engine->evaluate("throw \"RangeError: byteLength - byteOffset not a multiple of BYTES_PER_ELEMENT\"");
}
quint32 length = (arrayBuffer->size() - byteOffset) / cls->_bytesPerElement;
newObject = cls->newInstance(bufferArg, byteOffset, length);
} else {
QScriptValue lengthArg = (context->argumentCount() > 2) ? context->argument(2) : QScriptValue();
if (!lengthArg.isNumber()) {
engine->evaluate("throw \"ArgumentError: 3nd arg is not a number\"");
return QScriptValue();
}
if (lengthArg.toInt32() < 0 ||
byteOffsetArg.toInt32() + lengthArg.toInt32() * (qint32)(cls->_bytesPerElement) > arrayBuffer->size()) {
engine->evaluate("throw \"RangeError: byteLength out of range\"");
return QScriptValue();
}
quint32 length = lengthArg.toInt32();
// case for well-defined range
newObject = cls->newInstance(bufferArg, byteOffset, length);
}
}
} else if (context->argument(0).isNumber()) {
// case for new ArrayBuffer
newObject = cls->newInstance(context->argument(0).toInt32());
} else {
newObject = cls->newInstance(bufferArg);
}
if (context->isCalledAsConstructor()) {
// if called with the new keyword, replace this object
context->setThisObject(newObject);
return engine->undefinedValue();
}
return newObject;
}
