Floating point values set by Script cause Floating point truncated when passed to BT::InputPort<float> #506
Description
Hi, I'm using BehaviorTree.cpp version 4.0.1.
According to the docs
If you are migrating from BT.CPP 3.X, Script is a drop-in replacement for SetBlackboard, which is now discouraged.
However, I'm noticing a different behavior between the Script and SetBlackboard nodes when setting floating point values.
In particular, it looks like the following two blocks yield different results
<Action ID="SetBlackboard" output_key="data" value="0.1"/>
<Script code=" data:=0.1 "/>
Passing data to a BT::InputPort<float> results in a Floating point truncated error if using the script, while it works if using the set blackboard.
It looks like the script sets the value to a double (indeed if I change the input port to be double, the exception goes away).
Is this behavior expected? Should there be a way to specify floats using the scripting language?
See a minimal reproducible example
class CheckFloat : public BT::SyncActionNode
{
public:
CheckFloat(const std::string& name, const BT::NodeConfig& config)
: BT::SyncActionNode(name, config)
{ }
static BT::PortsList providedPorts()
{
return { BT::InputPort<float>("in_value") };
}
BT::NodeStatus tick() override
{
auto data = getInput<float>("in_value");
if (!data) {
throw BT::RuntimeError("missing required input: ", data.error());
}
std::cout << "Robot says: " << data.value() << std::endl;
return BT::NodeStatus::SUCCESS;
}
};
int main()
{
auto my_factory = std::make_unique<BT::BehaviorTreeFactory>();
my_factory->registerNodeType<CheckFloat>("CheckFloat");
std::stringstream bt_tree_text;
bt_tree_text << R"(
<root BTCPP_format="4">
<BehaviorTree ID="MainTree">
<Sequence>
<Script code=" data:=0.1 "/>
<Action ID="CheckFloat" in_value="{data}"/>
</Sequence>
</BehaviorTree>
</root>)";
auto tree = my_factory->createTreeFromText(bt_tree_text.str());
tree.tickWhileRunning();
return 0;
}