Add slippery group for nodes (players/items slide)

3 files changed, 25 insertions, 8 deletions

diff --git a/src/client.cpp b/src/client.cpp
index 39bb1e2ff..f7834a02b 100644
--- a/src/client.cpp
+++ b/src/client.cpp
@@ -403,7 +403,7 @@ void Client::step(float dtime)
 	// Control local player (0ms)
 	LocalPlayer *player = m_env.getLocalPlayer();
 	assert(player);
-	player->applyControl(dtime);
+	player->applyControl(dtime, &m_env);
 
 	// Step environment
 	m_env.step(dtime);
diff --git a/src/localplayer.cpp b/src/localplayer.cpp
index f04be07d6..f72da1b18 100644
--- a/src/localplayer.cpp
+++ b/src/localplayer.cpp
@@ -444,7 +444,7 @@ void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d)
 	move(dtime, env, pos_max_d, NULL);
 }
 
-void LocalPlayer::applyControl(float dtime)
+void LocalPlayer::applyControl(float dtime, ClientEnvironment *env)
 {
 	// Clear stuff
 	swimming_vertical = false;
@@ -660,9 +660,16 @@ void LocalPlayer::applyControl(float dtime)
 	else
 		incH = incV = movement_acceleration_default * BS * dtime;
 
+	INodeDefManager *nodemgr = env->getGameDef()->ndef();
+	Map *map = &env->getMap();
+	bool slippery = false;
+	const ContentFeatures &f = nodemgr->get(map->getNodeNoEx(getStandingNodePos()));
+	slippery = itemgroup_get(f.groups, "slippery");
 	// Accelerate to target speed with maximum increment
-	accelerateHorizontal(speedH * physics_override_speed, incH * physics_override_speed);
-	accelerateVertical(speedV * physics_override_speed, incV * physics_override_speed);
+	accelerateHorizontal(speedH * physics_override_speed,
+			incH * physics_override_speed, slippery);
+	accelerateVertical(speedV * physics_override_speed,
+			incV * physics_override_speed);
 }
 
 v3s16 LocalPlayer::getStandingNodePos()
@@ -699,12 +706,20 @@ v3f LocalPlayer::getEyeOffset() const
 }
 
 // Horizontal acceleration (X and Z), Y direction is ignored
-void LocalPlayer::accelerateHorizontal(const v3f &target_speed, const f32 max_increase)
+void LocalPlayer::accelerateHorizontal(const v3f &target_speed,
+	const f32 max_increase, bool slippery)
 {
         if (max_increase == 0)
                 return;
 
-        v3f d_wanted = target_speed - m_speed;
+	v3f d_wanted = target_speed - m_speed;
+	if (slippery) {
+		if (target_speed == v3f(0))
+			d_wanted = -m_speed * 0.05f;
+		else
+			d_wanted = target_speed * 0.1f - m_speed * 0.1f;
+	}
+
         d_wanted.Y = 0;
         f32 dl = d_wanted.getLength();
         if (dl > max_increase)
diff --git a/src/localplayer.h b/src/localplayer.h
index 9f7e92128..67b22b656 100644
--- a/src/localplayer.h
+++ b/src/localplayer.h
@@ -29,6 +29,7 @@ class Client;
 class Environment;
 class GenericCAO;
 class ClientActiveObject;
+class ClientEnvironment;
 class IGameDef;
 
 enum LocalPlayerAnimations
@@ -78,7 +79,7 @@ public:
 	void old_move(f32 dtime, Environment *env, f32 pos_max_d,
 			std::vector<CollisionInfo> *collision_info);
 
-	void applyControl(float dtime);
+	void applyControl(float dtime, ClientEnvironment *env);
 
 	v3s16 getStandingNodePos();
 	v3s16 getFootstepNodePos();
@@ -143,7 +144,8 @@ public:
 	void setCollisionbox(const aabb3f &box) { m_collisionbox = box; }
 
 private:
-	void accelerateHorizontal(const v3f &target_speed, const f32 max_increase);
+	void accelerateHorizontal(const v3f &target_speed,
+		const f32 max_increase, bool slippery);
 	void accelerateVertical(const v3f &target_speed, const f32 max_increase);
 	bool updateSneakNode(Map *map, const v3f &position, const v3f &sneak_max);