LogicEngine¶

class rlogic::LogicEngine¶

Central object which creates and manages the lifecycle and execution of scripts, bindings, and all other objects supported by the Ramses Logic library. All objects created by this class’ methods must be destroyed with destroy!

Use the create[Type] methods to create various objects, use destroy() to delete them.
Use link and unlink to connect data properties between these objects
use update() to trigger the execution of all objects

Public Functions

LogicEngine() noexcept¶: Constructor of LogicEngine.

~LogicEngine() noexcept¶: Destructor of LogicEngine

Collection<LogicObject> logicObjects() const¶

Returns an iterable rlogic::Collection of all rlogic::LogicObject instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::LogicObject instances created by this LogicEngine

Collection<LuaScript> scripts() const¶

Returns an iterable rlogic::Collection of all rlogic::LuaScript instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::LuaScript instances created by this LogicEngine

Collection<LuaModule> luaModules() const¶

Returns an iterable rlogic::Collection of all rlogic::LuaModule instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::LuaModule instances created by this LogicEngine

Collection<RamsesNodeBinding> ramsesNodeBindings() const¶

Returns an iterable rlogic::Collection of all rlogic::RamsesNodeBinding instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::RamsesNodeBinding instances created by this LogicEngine

Collection<RamsesAppearanceBinding> ramsesAppearanceBindings() const¶

Returns an iterable rlogic::Collection of all rlogic::RamsesAppearanceBinding instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::RamsesAppearanceBinding created by this LogicEngine

Collection<RamsesCameraBinding> ramsesCameraBindings() const¶

Returns an iterable rlogic::Collection of all rlogic::RamsesCameraBinding instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::RamsesCameraBinding created by this LogicEngine

Collection<DataArray> dataArrays() const¶

Returns an iterable rlogic::Collection of all rlogic::DataArray instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::DataArray created by this LogicEngine

Collection<AnimationNode> animationNodes() const¶

Returns an iterable rlogic::Collection of all rlogic::AnimationNode instances created by this LogicEngine.

Return: an iterable rlogic::Collection with all rlogic::AnimationNode created by this LogicEngine

const LogicObject *findLogicObject(std::string_view name) const¶

Returns a pointer to the first occurrence of an object with a given name regardless of its type. To convert the object to a concrete type (e.g. LuaScript) use rlogic::LogicObject::as<Type>() e.g.: auto myLuaScript = logicEngine.findLogicObject(“myLuaScript”)->as<LuaScript>()); Be aware that this function behaves as dynamic_cast and will return nullptr (without error) if given type doesn’t match the objects type. This can later lead to crash if ignored.

Return

a pointer to the logic object, or nullptr if none was found

Parameters

name: the name of the logic object to search for

LogicObject *findLogicObject(std::string_view name)¶

Returns a pointer to the first occurrence of an object with a given name regardless of its type. To convert the object to a concrete type (e.g. LuaScript) use rlogic::LogicObject::as<Type>() e.g.: auto myLuaScript = logicEngine.findLogicObject(“myLuaScript”)->as<LuaScript>()); Be aware that this function behaves as dynamic_cast and will return nullptr (without error) if given type doesn’t match the objects type. This can later lead to crash if ignored.

Return

a pointer to the logic object, or nullptr if none was found

Parameters

name: the name of the logic object to search for

const LuaScript *findScript(std::string_view name) const¶

Returns a pointer to the first occurrence of a script with a given name if such exists, and nullptr otherwise.

Return

a pointer to the script, or nullptr if none was found

Parameters

name: the name of the script to search for

LuaScript *findScript(std::string_view name)¶

Returns a pointer to the first occurrence of a script with a given name if such exists, and nullptr otherwise.

Return

a pointer to the script, or nullptr if none was found

Parameters

name: the name of the script to search for

const LuaModule *findLuaModule(std::string_view name) const¶

Returns a pointer to the first occurrence of a rlogic::LuaModule with a given name if such exists, and nullptr otherwise.

Return

a pointer to the script, or nullptr if none was found

Parameters

name: the name of the module to search for

LuaModule *findLuaModule(std::string_view name)¶

Returns a pointer to the first occurrence of a script with a given name if such exists, and nullptr otherwise.

Return

a pointer to the script, or nullptr if none was found

Parameters

name: the name of the script to search for

const RamsesNodeBinding *findNodeBinding(std::string_view name) const¶

Returns a pointer to the first occurrence of a node binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the node binding, or nullptr if none was found

Parameters

name: the name of the node binding to search for

RamsesNodeBinding *findNodeBinding(std::string_view name)¶

Returns a pointer to the first occurrence of a node binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the node binding, or nullptr if none was found

Parameters

name: the name of the node binding to search for

const RamsesAppearanceBinding *findAppearanceBinding(std::string_view name) const¶

Returns a pointer to the first occurrence of an appearance binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the appearance binding, or nullptr if none was found

Parameters

name: the name of the appearance binding to search for

RamsesAppearanceBinding *findAppearanceBinding(std::string_view name)¶

Returns a pointer to the first occurrence of an appearance binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the appearance binding, or nullptr if none was found

Parameters

name: the name of the appearance binding to search for

const RamsesCameraBinding *findCameraBinding(std::string_view name) const¶

Returns a pointer to the first occurrence of a camera binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the camera binding, or nullptr if none was found

Parameters

name: the name of the camera binding to search for

RamsesCameraBinding *findCameraBinding(std::string_view name)¶

Returns a pointer to the first occurrence of a camera binding with a given name if such exists, and nullptr otherwise.

Return

a pointer to the camera binding, or nullptr if none was found

Parameters

name: the name of the camera binding to search for

const DataArray *findDataArray(std::string_view name) const¶

Returns a pointer to the first occurrence of a rlogic::DataArray with a given name if such exists, and nullptr otherwise.

Return

a pointer to the rlogic::DataArray, or nullptr if none was found

Parameters

name: the name of the rlogic::DataArray to search for

DataArray *findDataArray(std::string_view name)¶

Returns a pointer to the first occurrence of a rlogic::DataArray with a given name if such exists, and nullptr otherwise.

Return

a pointer to the rlogic::DataArray, or nullptr if none was found

Parameters

name: the name of the rlogic::DataArray to search for

const AnimationNode *findAnimationNode(std::string_view name) const¶

Returns a pointer to the first occurrence of an rlogic::AnimationNode with a given name if such exists, and nullptr otherwise.

Return

a pointer to the rlogic::AnimationNode, or nullptr if none was found

Parameters

name: the name of the rlogic::AnimationNode to search for

AnimationNode *findAnimationNode(std::string_view name)¶

Returns a pointer to the first occurrence of an rlogic::AnimationNode with a given name if such exists, and nullptr otherwise.

Return

a pointer to the rlogic::AnimationNode, or nullptr if none was found

Parameters

name: the name of the rlogic::AnimationNode to search for

LuaScript *createLuaScript(std::string_view source, const LuaConfig &config = {}, std::string_view scriptName = "")¶

Creates a new Lua script from a source string. Refer to the rlogic::LuaScript class for requirements which Lua scripts must fulfill in order to be added to the LogicEngine. You can optionally provide Lua module dependencies via the config, they will be accessible under their configured alias name for use by the script. The provided module dependencies must exactly match the declared dependencies in source code (see extractLuaDependencies).

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors. The script can be destroyed by calling the destroy method

Parameters

source: the Lua source code
config: configuration options, e.g. for module dependencies
scriptName: name to assign to the script once it’s created

LuaModule *createLuaModule(std::string_view source, const LuaConfig &config = {}, std::string_view moduleName = "")¶

Creates a new rlogic::LuaModule from Lua source code. LuaModules can be used to share code and data constants across scripts or other modules. See also createLuaScript and rlogic::LuaConfig for details. You can optionally provide Lua module dependencies via the config, they will be accessible under their configured alias name for use by the module. The provided module dependencies must exactly match the declared dependencies in source code (see extractLuaDependencies).

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors. The script can be destroyed by calling the destroy method

Parameters

source: module source code
config: configuration options, e.g. for module dependencies
moduleName: name to assign to the module once it’s created

bool extractLuaDependencies(std::string_view source, const std::function<void(const std::string&)> &callbackFunc)¶

Extracts dependencies from a Lua script or module source code so that the corresponding modules can be provided when creating rlogic::LuaScript or rlogic::LuaModule.

Any rlogic::LuaScript or rlogic::LuaModule which has a module dependency, i.e. it requires another rlogic::LuaModule for it to work, must explicitly declare these dependencies directly in their source code by calling function ‘modules’ in global space and pass list of module names it depends on, for example:

modules("foo", "bar")
function interface()
  OUT.x = foo.myType()
end
function run()
  OUT.x = bar.doSth()
end

The ‘modules’ function does not affect any other part of the source code in any way, it is used only for the purpose of explicit declaration and extraction of its dependencies.

Please note that script runtime errors are ignored during extraction. In case a runtime error prevents the ‘modules’ function to be called, this method will still succeed but will not extract any modules, i.e. will not call callbackFunc. It is therefore highly recommended to put the modules declaration always at the beginning of every script before any other code so it will get executed even if there is runtime error later in the code.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if extraction succeeded (also if no dependencies found) or false if something went wrong. In that case, use getErrors() to obtain errors.

Parameters

source: source code of module or script to parse for dependencies
callbackFunc: function callback will be called for each dependency found

RamsesNodeBinding *createRamsesNodeBinding(ramses::Node &ramsesNode, ERotationType rotationType = ERotationType::Euler_XYZ, std::string_view name = "")¶

Creates a new rlogic::RamsesNodeBinding which can be used to set the properties of a Ramses Node object. The initial values of the binding’s properties are loaded from the ramsesNode. Rotation values are taken over from the ramsesNode only if the conventions are compatible (see rlogic::ERotationType).

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors. The binding can be destroyed by calling the destroy method

Parameters

ramsesNode: the ramses::Node object to control with the binding.
rotationType: the type of rotation to use (will affect the ‘rotation’ property semantics and type).
name: a name for the new rlogic::RamsesNodeBinding.

RamsesAppearanceBinding *createRamsesAppearanceBinding(ramses::Appearance &ramsesAppearance, std::string_view name = "")¶

Creates a new rlogic::RamsesAppearanceBinding which can be used to set the properties of a Ramses Appearance object.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors. The binding can be destroyed by calling the destroy method

Parameters

ramsesAppearance: the ramses::Appearance object to control with the binding.
name: a name for the the new rlogic::RamsesAppearanceBinding.

RamsesCameraBinding *createRamsesCameraBinding(ramses::Camera &ramsesCamera, std::string_view name = "")¶

Creates a new rlogic::RamsesCameraBinding which can be used to set the properties of a Ramses Camera object.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors. The binding can be destroyed by calling the destroy method

Parameters

ramsesCamera: the ramses::Camera object to control with the binding.
name: a name for the the new rlogic::RamsesCameraBinding.

template<typename T> DataArray *createDataArray(const std::vector<T> &data, std::string_view name = "")¶

Creates a new rlogic::DataArray to store data which can be used with animations. Provided data must not be empty otherwise creation will fail. See rlogic::CanPropertyTypeBeStoredInDataArray and rlogic::PropertyTypeToEnum to determine supported types that can be used to create a rlogic::DataArray.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors.

Parameters

data: source data to move into rlogic::DataArray, must not be empty.
name: a name for the the new rlogic::DataArray.

AnimationNode *createAnimationNode(const AnimationChannels &channels, std::string_view name = "")¶

Creates a new rlogic::AnimationNode for animating properties. Refer to rlogic::AnimationNode for more information about its use. There must be at least one channel provided, please see rlogic::AnimationChannel requirements for all the data.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

a pointer to the created object or nullptr if something went wrong during creation. In that case, use getErrors() to obtain errors.

Parameters

channels: list of animation channels to be animated with this animation node.
name: a name for the the new rlogic::AnimationNode.

bool update()¶

Updates all rlogic::LogicNode’s which were created by this LogicEngine instance. The order in which rlogic::LogicNode’s are executed is determined by the links created between them (see link and unlink). rlogic::LogicNode’s which don’t have any links between then are executed in arbitrary order, but the order is always the same between two invocations of update without any calls to link or unlink between them. As an optimization rlogic::LogicNode’s are only updated, if at least one input of a rlogic::LogicNode has changed since the last call to update. If the links between logic nodes create a loop, this method will fail with an error and will not execute any of the logic nodes.

Attention! This method clears all previous errors! See also docs of getErrors()

Return: true if the update was successful, false otherwise In case of an error, use getErrors() to obtain errors.

bool link(const Property &sourceProperty, const Property &targetProperty)¶

Links a property of a rlogic::LogicNode to another rlogic::Property of another rlogic::LogicNode. After linking, calls to update will propagate the value of sourceProperty to the targetProperty. Creating links influences the order in which scripts are executed - if node A provides data to node B, then node A will be executed before node B. A single output property (sourceProperty) can be linked to any number of input properties (targetProperty), but any input property can have at most one link to an output property (links are directional and support a 1-to-N relationships).

The link() method will fail when:

sourceProperty and targetProperty belong to the same rlogic::LogicNode
sourceProperty is not an output (see rlogic::LogicNode::getOutputs())
targetProperty is not an input (see rlogic::LogicNode::getInputs())
either sourceProperty or targetProperty is not a primitive property (you have to link sub-properties of structs and arrays individually)

Creating link loops will cause the next call to update() to fail with an error. Loops are directional, it is OK to have A->B, A->C and B->C, but is not OK to have A->B->C->A.

After calling link, the value of the targetProperty will not change until the next call to update. Creating and destroying links generally has no effect until update is called.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if linking was successful, false otherwise. To get more detailed error information use getErrors()

Parameters

sourceProperty: the output property which will provide data for targetProperty
targetProperty: the target property which will receive its value from sourceProperty

bool unlink(const Property &sourceProperty, const Property &targetProperty)¶

Unlinks two properties which were linked with link. After a link is destroyed, calls to update will no longer propagate the output value from the sourceProperty to the input value of the targetProperty. The value of the targetProperty will remain as it was after the last call to update - it will not be restored to a default value or to any value which was set manually with calls to rlogic::Property::set().

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if unlinking was successful, false otherwise. To get more detailed error information use getErrors().

Parameters

sourceProperty: the output property which is currently linked to targetProperty
targetProperty: the property which will no longer receive the value from sourceProperty

bool isLinked(const LogicNode &logicNode) const¶

Checks if an input or output of a given LogicNode is linked to another LogicNode

Return

true if the given LogicNode is linked to any other LogicNode, false otherwise.

Parameters

logicNode: the node to check for linkage.

const std::vector<ErrorData> &getErrors() const¶

Returns the list of all errors which occurred during the last API call to a LogicEngine method or any other method of its subclasses (scripts, bindings etc). Note that errors get wiped by all mutable methods of the LogicEngine.

This method can be used in two different ways:

To debug the correct usage of the Logic Engine API (e.g. by wrapping all API calls with a check for their return value and using this method to find out the cause of the error)
To check for runtime errors of scripts which come from a dynamic source, e.g. by calling the method after an unsuccessful call to update() with a faulty script

Return: a list of errors

bool destroy(LogicObject &object)¶

Destroys an instance of an object created with LogicEngine. All objects created using LogicEngine derive from a base class rlogic::LogicObject and can be destroyed using this method.

In case of a rlogic::LogicNode and its derived classes, if any links are connected to this rlogic::LogicNode, they will be destroyed too. Note that after this call, the execution order of rlogic::LogicNode may change! See the docs of link and unlink for more information.

In case of a rlogic::DataArray, destroy will fail if it is used in any rlogic::AnimationNode’s rlogic::AnimationChannel.

In case of a rlogic::LuaModule, destroy will fail if it is used in any rlogic::LuaScript.

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if object destroyed, false otherwise. Call getErrors() for error details upon failure.

Parameters

object: the object instance to destroy

bool saveToFile(std::string_view filename)¶

Writes the whole LogicEngine and all of its objects to a binary file with the given filename. The RAMSES scene potentially referenced by rlogic::RamsesBinding objects is not saved - that is left to the application. LogicEngine saves the references to those object, and restores them after loading. Thus, deleting Ramses objects which are being referenced from within the LogicEngine will result in errors if the Logic Engine is loaded from the file again. Note that it is not sufficient to have objects with the same name, they have to be the exact same objects as during saving! For more in-depth information regarding saving and loading, refer to the online documentation at https://ramses-logic.readthedocs.io/en/latest/api.html#saving-loading-from-file

Note: The method reports error and aborts if the rlogic::RamsesBinding objects reference more than one Ramses scene (this is acceptable during runtime, but not for saving to file).

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if saving was successful, false otherwise. To get more detailed error information use getErrors()

Parameters

filename: path to file to save the data (relative or absolute). The file will be created or overwritten if it exists!

bool loadFromFile(std::string_view filename, ramses::Scene *ramsesScene = nullptr, bool enableMemoryVerification = true)¶

Loads the whole LogicEngine data from the given file. See also saveToFile(). After loading, the previous state of the LogicEngine will be overwritten with the contents loaded from the file, i.e. all previously created objects (scripts, bindings, etc.) will be deleted and pointers to them will be invalid. The (optionally) provided ramsesScene will be used to resolve potential rlogic::RamsesBinding objects which point to Ramses objects. You can provide a nullptr if you know for sure that the LogicEngine loaded from the file has no rlogic::RamsesBinding objects which point to a Ramses scene object. Otherwise, the call to loadFromFile will fail with an error. In case of errors, the LogicEngine may be left in an inconsistent state. For more in-depth information regarding saving and loading, refer to the online documentation at https://ramses-logic.readthedocs.io/en/latest/api.html#saving-loading-from-file

Attention! This method clears all previous errors! See also docs of getErrors()

Return

true if deserialization was successful, false otherwise. To get more detailed error information use getErrors()

Parameters

filename: path to file from which to load content (relative or absolute)
ramsesScene: pointer to the Ramses Scene which holds the objects referenced in the Ramses Logic file
enableMemoryVerification: flag to enable memory verifier (a flatbuffers feature which checks bounds and ranges). Disable this only if the file comes from a trusted source and performance is paramount.

bool loadFromBuffer(const void *rawBuffer, size_t bufferSize, ramses::Scene *ramsesScene = nullptr, bool enableMemoryVerification = true)¶

Loads the whole LogicEngine data from the given memory buffer. This method is equivalent to loadFromFile but allows to have the file-opening logic done by the user and only pass the data as a buffer. The logic engine only reads the data, does not take ownership of it and does not modify it. The memory can be freed or modified after the call returns, the LogicEngine keeps no references to it.

Return

true if deserialization was successful, false otherwise. To get more detailed error information use getErrors()

Parameters

rawBuffer: pointer to the raw data in memory
bufferSize: size of the data (bytes)
ramsesScene: pointer to the Ramses Scene which holds the objects referenced in the Ramses Logic file
enableMemoryVerification: flag to enable memory verifier (a flatbuffers feature which checks bounds and ranges). Disable this only if the file comes from a trusted source and performance is paramount.

LogicEngine(const LogicEngine &other) = delete¶

Copy Constructor of LogicEngine is deleted because logic engines hold named resources and are not supposed to be copied

Parameters

other: logic engine to copy from

LogicEngine(LogicEngine &&other) noexcept¶

Move Constructor of LogicEngine

Parameters

other: logic engine to move from

LogicEngine &operator=(const LogicEngine &other) = delete¶

Assignment operator of LogicEngine is deleted because logic engines hold named resources and are not supposed to be copied

Parameters

other: logic engine to assign from

LogicEngine &operator=(LogicEngine &&other) noexcept¶

Move assignment operator of LogicEngine

Parameters

other: logic engine to move from

Public Members

std::unique_ptr<internal::LogicEngineImpl> m_impl¶: Implementation detail of LogicEngine