Refine/fix block jump physics

doc/client_lua_api.md

@@ -721,6 +721,8 @@ Methods:
             liquid_sink = float,
             sneak = boolean,
             sneak_glitch = boolean,
+            upward_rejump = boolean,
+            loose_lips = boolean,
             new_move = boolean,
         }
         ```

doc/lua_api.md

@@ -8825,6 +8825,9 @@ child will follow movement and rotation of that bone.
         * `sneak_glitch`: whether player can use the new move code replications
           of the old sneak side-effects: sneak ladders and 2 node sneak jump
           (default: `false`)
+        * `upward_rejump`: legacy ability to jump again while contacting a jumpable surface mid-jump
+          (default: `false`)
+        * `loose_lips`: legacy step-up while jumping into the corner of a node (default: `false`)
         * `new_move`: use new move/sneak code. When `false` the exact old code
           is used for the specific old sneak behavior (default: `true`)
     * Note: All numeric fields above modify a corresponding `movement_*` setting.

src/client/content_cao.cpp

@@ -1581,9 +1581,11 @@ void GenericCAO::processMessage(const std::string &data)
 		phys.gravity = readF32(is);
 
 		// MT 0.4.10 legacy: send inverted for detault `true` if the server sends nothing
-		phys.sneak        = !readU8(is);
-		phys.sneak_glitch = !readU8(is);
-		phys.new_move     = !readU8(is);
+		phys.sneak         = !readU8(is);
+		phys.sneak_glitch  = !readU8(is);
+		phys.upward_rejump = !readU8(is);
+		phys.loose_lips    = !readU8(is);
+		phys.new_move      = !readU8(is);
 
 		// new overrides since 5.8.0
 		if (canRead(is)) {

src/client/localplayer.cpp

@@ -320,8 +320,19 @@ void LocalPlayer::move(f32 dtime, Environment *env,
 
 	// Player object property step height is multiplied by BS in
 	// /src/script/common/c_content.cpp and /src/content_sao.cpp
-	float player_stepheight = (m_cao == nullptr) ? 0.0f :
-		(touching_ground ? m_cao->getStepHeight() : (0.2f * BS));
+	float player_stepheight = 0.0f;
+	if (m_cao != nullptr) {
+
+		const bool rising = m_speed.Y > 0.01f * BS;
+		const bool loose = physics_override.loose_lips;
+
+		const float snap_height =
+			(rising && !loose ? 0.05f : 0.2f) * BS;
+
+		player_stepheight = touching_ground
+			? m_cao->getStepHeight()
+			: snap_height;
+	}
 
 	v3f accel_f(0, -gravity, 0);
 	const v3f initial_position = position;
@@ -658,7 +669,7 @@ void LocalPlayer::applyControl(float dtime, Environment *env)
 				at its starting value
 			*/
 			v3f speedJ = getSpeed();
-			if (speedJ.Y >= -0.5f * BS) {
+			if (speedJ.Y >= -0.5f * BS && (physics_override.upward_rejump || speedJ.Y <= 0.0f * BS)) {
 				speedJ.Y = movement_speed_jump * physics_override.jump;
 				setSpeed(speedJ);
 				m_client->getEventManager()->put(new SimpleTriggerEvent(MtEvent::PLAYER_JUMP));

src/player.cpp

@@ -249,7 +249,7 @@ static auto tie(const PlayerPhysicsOverride &o)
 {
 	// Make sure to add new members to this list!
 	return std::tie(
-	o.speed, o.jump, o.gravity, o.sneak, o.sneak_glitch, o.new_move, o.speed_climb,
+	o.speed, o.jump, o.gravity, o.sneak, o.sneak_glitch, o.upward_rejump, o.loose_lips, o.new_move, o.speed_climb,
 	o.speed_crouch, o.liquid_fluidity, o.liquid_fluidity_smooth, o.liquid_sink,
 	o.acceleration_default, o.acceleration_air, o.speed_fast, o.acceleration_fast,
 	o.speed_walk

src/player.h

@@ -103,6 +103,8 @@ struct PlayerPhysicsOverride
 
 	bool sneak = true;
 	bool sneak_glitch = false;
+	bool upward_rejump = false;
+	bool loose_lips = false;
 	// "Temporary" option for old move code
 	bool new_move = true;
 

src/script/lua_api/l_localplayer.cpp

@@ -159,6 +159,12 @@ int LuaLocalPlayer::l_get_physics_override(lua_State *L)
 	lua_pushboolean(L, phys.sneak_glitch);
 	lua_setfield(L, -2, "sneak_glitch");
 
+	lua_pushboolean(L, phys.upward_rejump);
+	lua_setfield(L, -2, "upward_rejump");
+
+	lua_pushboolean(L, phys.loose_lips);
+	lua_setfield(L, -2, "loose_lips");
+
 	lua_pushboolean(L, phys.new_move);
 	lua_setfield(L, -2, "new_move");
 

src/script/lua_api/l_object.cpp

@@ -1744,6 +1744,8 @@ int ObjectRef::l_set_physics_override(lua_State *L)
 	getfloatfield(L, 2, "gravity", phys.gravity);
 	getboolfield(L, 2, "sneak", phys.sneak);
 	getboolfield(L, 2, "sneak_glitch", phys.sneak_glitch);
+	getboolfield(L, 2, "upward_rejump", phys.upward_rejump);
+	getboolfield(L, 2, "loose_lips", phys.loose_lips);
 	getboolfield(L, 2, "new_move", phys.new_move);
 	getfloatfield(L, 2, "speed_climb", phys.speed_climb);
 	getfloatfield(L, 2, "speed_crouch", phys.speed_crouch);

src/server/player_sao.cpp

@@ -320,6 +320,8 @@ std::string PlayerSAO::generateUpdatePhysicsOverrideCommand() const
 	// MT 0.4.10 legacy: send inverted for detault `true` if the server sends nothing
 	writeU8(os, !phys.sneak);
 	writeU8(os, !phys.sneak_glitch);
+	writeU8(os, !phys.upward_rejump);
+	writeU8(os, !phys.loose_lips);
 	writeU8(os, !phys.new_move);
 	// new physics overrides since 5.8.0
 	writeF32(os, phys.speed_climb);