Implement and use applyOffset()

rwengine/src/ai/TrafficDirector.cpp

@@ -155,8 +155,6 @@ std::vector<GameObject*> TrafficDirector::populateNearby(
 
     // We have not reached the limit of spawned pedestrians
     if (availablePeds > 0) {
-        static const glm::vec3 kSpawnOffset{0.f, 0.f, 1.f};
-
         int counter = availablePeds;
         // maxSpawn can be -1 for "as many as possible"
         if (maxSpawn > -1) {
@@ -178,8 +176,8 @@ std::vector<GameObject*> TrafficDirector::populateNearby(
             // Spawn a pedestrian from the available pool
             const uint16_t pedId = peds[std::uniform_int_distribution<>(
                 0, peds.size() - 1)(random)];
-            auto ped = world->createPedestrian(pedId,
-                                           spawn->position + kSpawnOffset);
+            auto ped = world->createPedestrian(pedId, spawn->position);
+            ped->applyOffset();
             ped->setLifetime(GameObject::TrafficLifetime);
             ped->controller->setGoal(CharacterController::TrafficWander);
             created.push_back(ped);
@@ -190,8 +188,6 @@ std::vector<GameObject*> TrafficDirector::populateNearby(
 
     // We have not reached the limit of spawned vehicles
     if (availableCars > 0) {
-        static const glm::vec3 kSpawnOffset{0.f, 0.f, 1.f};
-
         int counter = availableCars;
         // maxSpawn can be -1 for "as many as possible"
         if (maxSpawn > -1) {
@@ -249,7 +245,8 @@ std::vector<GameObject*> TrafficDirector::populateNearby(
             // Spawn a vehicle from the available pool
             const uint16_t carId = cars[std::uniform_int_distribution<>(
                 0, cars.size() - 1)(random)];
-            auto vehicle = world->createVehicle(carId, next->position + kSpawnOffset + diff + laneOffset, orientation);
+            auto vehicle = world->createVehicle(carId, next->position + diff + laneOffset, orientation);
+            vehicle->applyOffset();
             vehicle->setLifetime(GameObject::TrafficLifetime);
             vehicle->setHandbraking(false);
 

rwengine/src/objects/CharacterObject.cpp

@@ -423,16 +423,23 @@ void CharacterObject::updateCharacter(float dt) {
 void CharacterObject::setPosition(const glm::vec3& pos) {
     auto realPos = pos;
     if (physCharacter) {
-        if (pos.z <= -99.f) {
+        if (pos.z <= -100.f) {
             realPos = engine->getGroundAtPosition(pos);
         }
-        btVector3 bpos(realPos.x, realPos.y, realPos.z + 1.0f);
+        btVector3 bpos(realPos.x, realPos.y, realPos.z);
         physCharacter->warp(bpos);
     }
     position = realPos;
     getClump()->getFrame()->setTranslation(pos);
 }
 
+glm::vec3 CharacterObject::getCenterOffset() {
+    // Return an offset so that the feet are on the ground
+    const float z_offset =
+        physShape->getHalfHeight() + physShape->getRadius();
+    return glm::vec3(0.f, 0.f, z_offset);
+}
+
 bool CharacterObject::isPlayer() const {
     return engine->state->playerObject == getGameObjectID();
 }

rwengine/src/objects/CharacterObject.hpp

@@ -130,6 +130,8 @@ public:
 
     void setPosition(const glm::vec3& pos) override;
 
+    glm::vec3 getCenterOffset() override;
+
     bool isPlayer() const;
 
     bool isDying() const;

rwengine/src/objects/GameObject.hpp

@@ -148,6 +148,21 @@ public:
      */
     void setHeading(float heading);
 
+    /**
+     * @brief getCenterOffset Returns the offset from center of mass to base of model
+     * This function should be overwritten by a derived class
+     */
+    virtual glm::vec3 getCenterOffset() {
+        return glm::vec3(0.f, 0.f, 1.f);
+    }
+
+    /**
+     * @brief applyOffset Applies the offset from getCenterOffset to the object
+     */
+    void applyOffset() {
+         setPosition(getPosition() + getCenterOffset());
+    }
+
     struct DamageInfo {
         enum DamageType { Explosion, Burning, Bullet, Physics };
 

rwengine/src/objects/VehicleObject.cpp

@@ -282,6 +282,17 @@ void VehicleObject::setPosition(const glm::vec3& pos) {
     }
 }
 
+glm::vec3 VehicleObject::getCenterOffset() {
+    // Calculate the offset from the center to the base of the vehicle
+    btVector3 aabbMin;
+    btVector3 aabbMax;
+
+    collision->getBulletBody()->getAabb(aabbMin, aabbMax);
+    float z_offset = (aabbMax.z() - aabbMin.z()) / 2;
+
+    return glm::vec3(0.f, 0.f, z_offset);
+}
+
 void VehicleObject::setRotation(const glm::quat& orientation) {
     getClump()->getFrame()->setRotation(glm::mat3_cast(orientation));
     if (collision->getBulletBody()) {

rwengine/src/objects/VehicleObject.hpp

@@ -103,6 +103,8 @@ public:
 
     void setRotation(const glm::quat& orientation) override;
 
+    glm::vec3 getCenterOffset() override;
+
     void updateTransform(const glm::vec3& pos, const glm::quat& rot) override;
 
     VehicleModelInfo* getVehicle() const {

rwengine/src/script/ScriptFunctions.hpp

@@ -21,7 +21,6 @@
  * among many script modules and opcodes.
  */
 namespace script {
-const ScriptVec3 kSpawnOffset = ScriptVec3(0.f, 0.f, 1.f);
 
 inline void getObjectPosition(GameObject* object, ScriptFloat& x,
                               ScriptFloat& y, ScriptFloat& z) {
@@ -31,7 +30,8 @@ inline void getObjectPosition(GameObject* object, ScriptFloat& x,
     z = p.z;
 }
 inline void setObjectPosition(GameObject* object, const ScriptVec3& coord) {
-    object->setPosition(coord + script::kSpawnOffset);
+    object->setPosition(coord);
+    object->applyOffset();
 }
 
 inline VehicleObject* getCharacterVehicle(CharacterObject* character) {

rwengine/src/script/modules/GTA3ModuleImpl.inl

@@ -911,7 +911,8 @@ void opcode_0053(const ScriptArguments& args, const ScriptInt index, ScriptVec3
 
     coord = script::getGround(args, coord);
     /// @todo fix the API interfaces that are now totally incoherent
-    auto character = args.getWorld()->createPlayer(coord + script::kSpawnOffset);
+    auto character = args.getWorld()->createPlayer(coord);
+    character->applyOffset();
     player = static_cast<PlayerController*>(character->controller);
     args.getState()->playerObject = character->getGameObjectID();
 }
@@ -939,7 +940,8 @@ void opcode_0054(const ScriptArguments& args, const ScriptPlayer player, ScriptF
 */
 void opcode_0055(const ScriptArguments& args, const ScriptPlayer player, ScriptVec3 coord) {
     RW_UNUSED(args);
-    player->getCharacter()->setPosition(coord + script::kSpawnOffset);
+    player->getCharacter()->setPosition(coord);
+    player->getCharacter()->applyOffset();
 }
 
 /**
@@ -1790,7 +1792,8 @@ void opcode_009a(const ScriptArguments& args, const ScriptPedType pedType, const
     RW_UNUSED(pedType);
 
     coord = script::getGround(args, coord);
-    character = args.getWorld()->createPedestrian(model, coord + script::kSpawnOffset);
+    character = args.getWorld()->createPedestrian(model, coord);
+    character->applyOffset();
     character->setLifetime(GameObject::MissionLifetime);
 
     if (args.getThread()->isMission) {
@@ -1939,7 +1942,8 @@ bool opcode_00a4(const ScriptArguments& args, const ScriptCharacter character, c
 void opcode_00a5(const ScriptArguments& args, const ScriptModelID model, ScriptVec3 coord, ScriptVehicle& vehicle) {
     // @todo calculate distance from centre of mass to base of model and apply it as spawnOffset
     coord = script::getGround(args, coord);
-    vehicle = args.getWorld()->createVehicle(model, coord + script::kSpawnOffset);
+    vehicle = args.getWorld()->createVehicle(model, coord);
+    vehicle->applyOffset();
     vehicle->setLifetime(GameObject::MissionLifetime);
 
     if (args.getThread()->isMission) {
@@ -9948,7 +9952,8 @@ void opcode_0376(const ScriptArguments& args, ScriptVec3 coord,
     const auto& pedGroup = data->pedgroups.at(groupId);
     const auto model = pedGroup.at(args.getVM()->getRandomNumber(
         static_cast<std::size_t>(0), pedGroup.size() - 1));
-    character = world->createPedestrian(model, coord + script::kSpawnOffset);
+    character = world->createPedestrian(model, coord);
+    character->applyOffset();
 }
 
 /**