[VT]: Add a way to track VT float attributes

This lets you use the VT state helper to deal with float attributes.
Previously, float values may not have been handled correctly.

examples/seeder_example/vt_application.cpp

@@ -76,7 +76,7 @@ bool SeederVtApplication::initialize()
  VTClientUpdateHelper.add_tracked_numeric_value(currentAlarms2_ObjPtr);
 
  // Track the attribute values we want to update
- VTClientUpdateHelper.add_tracked_attribute(speed_OutNum, 8, 0.0036f);
+ VTClientUpdateHelper.add_tracked_attribute_float(speed_OutNum, 8, 0.0036f);
  VTClientUpdateHelper.add_tracked_attribute(section1Status_OutRect, 5, solidGreen_FillAttr);
  VTClientUpdateHelper.add_tracked_attribute(section2Status_OutRect, 5, solidYellow_FillAttr);
  VTClientUpdateHelper.add_tracked_attribute(section3Status_OutRect, 5, solidRed_FillAttr);

isobus/include/isobus/isobus/isobus_virtual_terminal_client_state_tracker.hpp

@@ -99,6 +99,12 @@ namespace isobus
  /// @param[in] initialValue The initial value of the attribute to track.
  void add_tracked_attribute(std::uint16_t objectId, std::uint8_t attribute, std::uint32_t initialValue = 0);
 
+ /// @brief Adds a float attribute to track.
+ /// @param[in] objectId The object id of the attribute to track.
+ /// @param[in] attribute The attribute to track. Make sure it's a float attribute!
+ /// @param[in] initialValue The initial value of the attribute to track.
+ void add_tracked_attribute_float(std::uint16_t objectId, std::uint8_t attribute, float initialValue = 0.0f);
+
  /// @brief Removes an attribute from tracking.
  /// @param[in] objectId The object id of the attribute to remove from tracking.
  /// @param[in] attribute The attribute to remove from tracking.
@@ -110,6 +116,12 @@ namespace isobus
  /// @return The value of the attribute of the tracked object.
  std::uint32_t get_attribute(std::uint16_t objectId, std::uint8_t attribute) const;
 
+ /// @brief Get the value of an attribute of a tracked object, if you tracked it with add_tracked_attribute_float.
+ /// @param[in] objectId The object id of the attribute to get.
+ /// @param[in] attribute The attribute to get.
+ /// @return The value of the attribute of the tracked object.
+ float get_attribute_float(std::uint16_t objectId, std::uint8_t attribute) const;
+
  protected:
  std::shared_ptr<ControlFunction> client; ///< The control function of the virtual terminal client to track.
  std::shared_ptr<ControlFunction> server; ///< The control function of the server the client is connected to.
@@ -134,6 +146,7 @@ namespace isobus
  std::uint8_t activeWorkingSetAddress = NULL_CAN_ADDRESS; ///< Holds the address of the control function that currently has
  std::map<std::uint16_t, std::uint16_t> softKeyMasks; ///< Holds the data/alarms masks with their associated soft keys masks for tracked objects.
  std::map<std::uint16_t, std::map<std::uint8_t, std::uint32_t>> attributeStates; ///< Holds the 'attribute' state of tracked objects.
+ std::map<std::uint16_t, std::map<std::uint8_t, float>> floatAttributeStates; ///< Holds the 'attribute' state of tracked objects, for attributes that use floats (scale, for example).
  //! TODO: std::map<std::uint16_t, std::uint8_t> alarmMaskPrioritiesStates; ///< Holds the 'alarm mask priority' state of tracked objects.
  //! TODO: std::map<std::uint16_t, std::pair<std::uint8_t, std::uint16_t>> listItemStates; ///< Holds the 'list item' state of tracked objects.
  //! TODO: add lock/unlock mask state

isobus/include/isobus/isobus/isobus_virtual_terminal_client_update_helper.hpp

@@ -74,6 +74,18 @@ namespace isobus
  /// @return True if the attribute was set successfully, false otherwise.
  bool set_attribute(std::uint16_t objectId, std::uint8_t attribute, std::uint32_t value);
 
+ /// @brief Sets the value of a float attribute of a tracked object.
+ /// @attention ONLY use this function for float attributes defined in ISO11783-6,
+ /// otherwise you will get incorrect results. Scale on output numbers, for example, is a float.
+ /// @note If the to be tracked working set consists of more than the master,
+ /// this function is incompatible with a VT prior to version 4. For working sets consisting
+ /// of only the master, this function is compatible with any VT version.
+ /// @param[in] objectId The object id of the attribute to set.
+ /// @param[in] attribute The attribute to set.
+ /// @param[in] value The value to set the attribute to.
+ /// @return True if the attribute was set successfully, false otherwise.
+ bool set_attribute(std::uint16_t objectId, std::uint8_t attribute, float value);
+
  private:
  /// @brief Processes a numeric value change event
  /// @param[in] event The numeric value change event to process.

isobus/src/isobus_virtual_terminal_client_state_tracker.cpp

@@ -160,6 +160,24 @@ namespace isobus
  attributeMap[attribute] = initialValue;
  }
 
+ void VirtualTerminalClientStateTracker::add_tracked_attribute_float(std::uint16_t objectId, std::uint8_t attribute, float initialValue)
+ {
+ if (floatAttributeStates.find(objectId) == floatAttributeStates.end())
+ {
+ floatAttributeStates[objectId] = {};
+ }
+
+ auto &attributeMap = floatAttributeStates.at(objectId);
+ if ((attributeMap.find(attribute) != attributeMap.end()) ||
+ (floatAttributeStates.find(attribute) != floatAttributeStates.end()))
+ {
+ LOG_WARNING("[VTStateHelper] add_tracked_attribute: attribute '%lu' of objectId '%lu' already tracked", attribute, objectId);
+ return;
+ }
+
+ attributeMap[attribute] = initialValue;
+ }
+
  void VirtualTerminalClientStateTracker::remove_tracked_attribute(std::uint16_t objectId, std::uint8_t attribute)
  {
  if (attributeStates.find(objectId) == attributeStates.end())
@@ -196,6 +214,37 @@ namespace isobus
  return attributeMap.at(attribute);
  }
 
+ float VirtualTerminalClientStateTracker::get_attribute_float(std::uint16_t objectId, std::uint8_t attribute) const
+ {
+ if (attributeStates.find(objectId) == attributeStates.end())
+ {
+ if (floatAttributeStates.find(objectId) == floatAttributeStates.end())
+ {
+ LOG_WARNING("[VTStateHelper] get_attribute_float: objectId '%lu' has no tracked float attributes", objectId);
+ return 0.0f;
+ }
+
+ const auto &floatAttributeMap = floatAttributeStates.at(objectId);
+ if (floatAttributeStates.find(attribute) == floatAttributeStates.end())
+ {
+ LOG_WARNING("[VTStateHelper] get_attribute_float: float attribute '%lu' of objectId '%lu' not tracked", attribute, objectId);
+ return 0;
+ }
+ return floatAttributeMap.at(attribute);
+ }
+ else
+ {
+ const auto &attributeMap = attributeStates.at(objectId);
+
+ if (attributeMap.find(attribute) != attributeMap.end())
+ {
+ LOG_WARNING("[VTStateHelper] get_attribute_float: attribute '%lu' of objectId '%lu' was tracked as an integer. You are calling the wrong function to get its value!", attribute, objectId);
+ return static_cast<float>(attributeMap.at(attribute));
+ }
+ }
+ return 0.0f;
+ }
+
  void VirtualTerminalClientStateTracker::cache_active_mask(std::uint16_t maskId)
  {
  if (activeDataOrAlarmMask != maskId)

isobus/src/isobus_virtual_terminal_client_update_helper.cpp

@@ -172,4 +172,34 @@ namespace isobus
  return success;
  }
 
+ bool VirtualTerminalClientUpdateHelper::set_attribute(std::uint16_t objectId, std::uint8_t attribute, float value)
+ {
+ if (nullptr == client)
+ {
+ LOG_ERROR("[VTStateHelper] set_attribute: client is nullptr");
+ return false;
+ }
+ if (floatAttributeStates.find(objectId) == floatAttributeStates.end())
+ {
+ LOG_ERROR("[VTStateHelper] set_attribute: objectId %lu has no float attributes tracked", objectId);
+ return false;
+ }
+ if (floatAttributeStates.at(objectId).find(attribute) == floatAttributeStates.at(objectId).end())
+ {
+ LOG_WARNING("[VTStateHelper] set_attribute: float attribute %lu of objectId %lu not tracked", attribute, objectId);
+ return false;
+ }
+ if (floatAttributeStates.at(objectId).at(attribute) == value)
+ {
+ return true;
+ }
+
+ bool success = vtClient->send_change_attribute(objectId, attribute, value);
+ if (success)
+ {
+ floatAttributeStates[objectId][attribute] = value;
+ }
+ return success;
+ }
+
 } // namespace isobus