o3de/Gems/EMotionFX/Code/Include/Integration/AnimationBus.h

/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */


#pragma once

#include <AzCore/EBus/EBus.h>
#include <AzCore/Component/ComponentBus.h>
#include <AzCore/Component/Entity.h>
#include <AzCore/std/containers/array.h>
#include <AzFramework/Physics/Common/PhysicsSceneQueries.h>


namespace EMotionFX
{
    class ActorInstance;
    class MotionInstance;

    namespace Integration
    {
        /**
         * EMotion FX System Request Bus
         * Used for making global requests to the EMotion FX system.
         */
        class SystemRequests
            : public AZ::EBusTraits
        {
        public:
            static const AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Single;
            static const AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::Single;
        };
        using SystemRequestBus = AZ::EBus<SystemRequests>;

        /**
         * EMotion FX System Notification Bus
         * Used for monitoring EMotion FX system-level events.
         */
        class SystemNotifications
            : public AZ::EBusTraits
        {
        public:
            static const AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Multiple;
            static const AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::Single;

            // Use this bus to register custom EMotionFX plugin.
            virtual void OnRegisterPlugin() = 0;
        };
        using SystemNotificationBus = AZ::EBus<SystemNotifications>;

        /**
         * Motion event descriptor.
         */
        struct MotionEvent
        {
        public:

            AZ_TYPE_INFO(MotionEvent, "{0C899DAC-6B19-4BDD-AD8C-8A11EF2A6729}");

            // Use fixed buffer for parameter string to avoid allocations for motion events, which can be sent at high frequency.
            enum { kMaxParameterStringLength = 64 - 1 };
            typedef AZStd::array<char, kMaxParameterStringLength + 1> ParameterStringStorage;

            ParameterStringStorage      m_parameterStorage;

            AZ::EntityId                m_entityId;         ///< EntityId associated with the originating actor
            const char*                 m_parameter;        ///< Optional string parameter
            EMotionFX::ActorInstance*   m_actorInstance;    ///< Pointer to the actor instance on which the event is playing
            const EMotionFX::MotionInstance*  m_motionInstance;   ///< Pointer to the motion instance from which the event was fired
            float                       m_time;             ///< Time value of the event, in seconds
            AZ::u32                     m_eventType;        ///< Type Id of the event. m_eventTypeName stores the string representation.
            const char*                 m_eventTypeName;    ///< Event type in string form
            float                       m_globalWeight;     ///< Global weight of the event
            float                       m_localWeight;      ///< Local weight of the event
            bool                        m_isEventStart;     ///< Is this the start of a ranged event? This is always true for one-shot events.

            MotionEvent()
                : m_actorInstance(nullptr)
                , m_motionInstance(nullptr)
                , m_time(0.f)
                , m_eventType(0)
                , m_eventTypeName(nullptr)
                , m_globalWeight(0.f)
                , m_localWeight(0.f)
                , m_isEventStart(false)
            {
                m_parameterStorage[0] = '\0';
                m_parameter = m_parameterStorage.data();
            }

            MotionEvent(const MotionEvent& rhs)
                : m_actorInstance(rhs.m_actorInstance)
                , m_motionInstance(rhs.m_motionInstance)
                , m_time(rhs.m_time)
                , m_eventType(rhs.m_eventType)
                , m_eventTypeName(rhs.m_eventTypeName)
                , m_globalWeight(rhs.m_globalWeight)
                , m_localWeight(rhs.m_localWeight)
                , m_isEventStart(rhs.m_isEventStart)
            {
                m_parameterStorage = rhs.m_parameterStorage;
                m_parameter = m_parameterStorage.data();
            }

            void SetParameterString(const char* str, size_t length)
            {
                if (length)
                {
                    const size_t truncatedLength = AZStd::GetMin<size_t>(length, MotionEvent::kMaxParameterStringLength);
                    azstrncpy(m_parameterStorage.data(), m_parameterStorage.size(), str, truncatedLength);
                    m_parameterStorage[truncatedLength] = '\0';
                }
                else
                {
                    m_parameterStorage[0] = '\0';
                }
            }
        };

        /**
         * EMotion FX Actor Notification Bus
         * Used for monitoring EMotion FX per-actor events.
         */
        class ActorNotifications
            : public AZ::ComponentBus
        {
        public:

            /// Bus is accessed from job threads as well as simulation threads.
            /// This allows events to be safely queued from anywhere, and flushed from the main simulation thread.
            static const bool EnableEventQueue = true;
            typedef AZStd::recursive_mutex MutexType;

            /// A motion event has fired during playback.
            /// \param motionEvent information about the event.
            virtual void OnMotionEvent(MotionEvent /*motionEvent*/) {}

            /// A motion has looped.
            /// \param motionName name of the motion.
            virtual void OnMotionLoop(const char* /*motionName*/) {}

            /// A anim graph state is about to be entered.
            /// \param stateName name of the state.
            virtual void OnStateEntering(const char* /*stateName*/) {}
            /// A anim graph state has been entered.
            /// \param stateName name of the state.
            virtual void OnStateEntered(const char* /*stateName*/) {}
            /// A anim graph state is about to be exited.
            /// \param stateName name of the state.
            virtual void OnStateExiting(const char* /*stateName*/) {}
            /// A anim graph state has been exited.
            /// \param stateName name of the state.
            virtual void OnStateExited(const char* /*stateName*/) {}

            /// A transition between states is beginning.
            /// \param fromState name of source state.
            /// \param toState name of target state.
            virtual void OnStateTransitionStart(const char* /*fromState*/, const char* /*toState*/) {}
            /// A transition between states has completed.
            /// \param fromState name of source state.
            /// \param toState name of target state.
            virtual void OnStateTransitionEnd(const char* /*fromState*/, const char* /*toState*/) {}
        };
        using ActorNotificationBus = AZ::EBus<ActorNotifications>;


        /**
         * The raycast request interface, which EMotion FX calls in order to perform ray cast tests.
         * This allows you to perform custom filtering.
         */
        class IRaycastRequests
        {
        public:
            AZ_TYPE_INFO(IRaycastRequests, "{DDA90B91-6F1D-4C83-A0E1-9DE1540B0968}");

            enum class UsecaseHint : AZ::u32
            {
                Generic,    /**< A generic raycast, so a non-specific use case. */
                FootPlant   /**< We are using this for foot planting. */
            };

            struct RaycastRequest
            {
                AZ::Vector3 m_start;        /**< The start position of the ray in world space. */
                AZ::Vector3 m_direction;    /**< The direction vector (has to be normalized). */
                float       m_distance;     /**< The maximum distance (has to be positive and larger than zero). */
                AzPhysics::SceneQuery::QueryType m_queryType = AzPhysics::SceneQuery::QueryType::StaticAndDynamic;
                UsecaseHint         m_hint          = UsecaseHint::Generic; /**< The use case hint. */
            };

            struct RaycastResult
            {
                AZ::Vector3 m_position      = AZ::Vector3::CreateZero();        /**< The intersection point. */
                AZ::Vector3 m_normal        = AZ::Vector3(0.0f, 0.0f, 1.0f);    /**< The normal at the intersection point. */
                bool        m_intersected   = false;  /**< Did we intersect? In case this is false, the m_position and m_normal should be ignored. */
            };
 
            /** 
             * Perform a raycast to try to find the intersecion point with the world.
             * Your game should implement this.
             * @param entityId The entity that is requesting this raycast. This entity will have an Actor component on it.
             * @param rayRequest The ray information, containing the start point, direction and length of the ray.
             * @result The resulting intersection, if there is any. If there is none the m_intersected member of the RaycastResult object returned will be set to false.
             */
            virtual RaycastResult Raycast(AZ::EntityId entityId, const RaycastRequest& rayRequest) = 0;
            virtual void EnableRayRequests() {}
            virtual void DisableRayRequests() {}
        }; 

    } // namespace Integration
} // namespace EMotionFX