ClickHouse/src/Functions/h3GetFaces.cpp
2022-02-18 16:34:50 -08:00

117 lines
3.5 KiB
C++

#include "config_functions.h"
#if USE_H3
#include <Columns/ColumnArray.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypeArray.h>
#include <DataTypes/DataTypesNumber.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunction.h>
#include <Common/typeid_cast.h>
#include <base/range.h>
#include <h3api.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int ILLEGAL_COLUMN;
}
namespace
{
class FunctionH3GetFaces : public IFunction
{
public:
static constexpr auto name = "h3GetFaces";
static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionH3GetFaces>(); }
std::string getName() const override { return name; }
size_t getNumberOfArguments() const override { return 1; }
bool useDefaultImplementationForConstants() const override { return true; }
bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return false; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
const auto * arg = arguments[0].get();
if (!WhichDataType(arg).isUInt64())
throw Exception(
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT,
"Illegal type {} of argument {} of function {}. Must be UInt64",
arg->getName(), 1, getName());
return std::make_shared<DataTypeArray>(std::make_shared<DataTypeUInt8>());
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override
{
auto non_const_arguments = arguments;
for (auto & argument : non_const_arguments)
argument.column = argument.column->convertToFullColumnIfConst();
const auto * column = checkAndGetColumn<ColumnUInt64>(non_const_arguments[0].column.get());
if (!column)
throw Exception(
ErrorCodes::ILLEGAL_COLUMN,
"Illegal type {} of argument {} of function {}. Must be UInt64.",
arguments[0].type->getName(),
1,
getName());
const auto & data = column->getData();
auto result_column_data = ColumnUInt8::create();
auto & result_data = result_column_data->getData();
auto result_column_offsets = ColumnArray::ColumnOffsets::create();
auto & result_offsets = result_column_offsets->getData();
result_offsets.resize(input_rows_count);
auto current_offset = 0;
std::vector<int> faces;
for (size_t row = 0; row < input_rows_count; ++row)
{
int max_faces = maxFaceCount(data[row]);
faces.resize(max_faces);
// function name h3GetFaces (v3.x) changed to getIcosahedronFaces (v4.0.0).
getIcosahedronFaces(data[row], faces.data());
for (int i = 0; i < max_faces; ++i)
{
// valid icosahedron faces are represented by integers 0-19
if (faces[i] >= 0 && faces[i] <= 19)
{
++current_offset;
result_data.emplace_back(faces[i]);
}
}
result_offsets[row] = current_offset;
faces.clear();
}
return ColumnArray::create(std::move(result_column_data), std::move(result_column_offsets));
}
};
}
void registerFunctionH3GetFaces(FunctionFactory & factory)
{
factory.registerFunction<FunctionH3GetFaces>();
}
}
#endif