Added fall damage and /kill (#959)

* add player health and fall damage and /kill

* less latency for taking damage

* clamp health

* changes

* final changes maybe

* return serverFailure if target not found

* fix error

* remove /damage

src/Inventory.zig

@@ -267,7 +267,7 @@ pub const Sync = struct { // MARK: Sync
 				defer main.stackAllocator.free(users);
 
 				for (users) |user| {
-					if (user == source) continue;
+					if (user == source and op.ignoreSource()) continue;
 					main.network.Protocols.inventory.sendSyncOperation(user.conn, syncData);
 				}
 			}
@@ -410,6 +410,14 @@ pub const Sync = struct { // MARK: Sync
 		}
 	};
 
+	pub fn addHealth(health: f32, cause: main.game.DamageType, side: Side, id: u32) void {
+		if (side == .client) {
+			Sync.ClientSide.executeCommand(.{.addHealth = .{.target = id, .health = health, .cause = cause}});
+		} else {
+			Sync.ServerSide.executeCommand(.{.addHealth = .{.target = id, .health = health, .cause = cause}}, null);
+		}
+	}
+
 	pub fn getInventory(id: u32, side: Side, user: ?*main.server.User) ?Inventory {
 		return switch(side) {
 			.client => ClientSide.getInventory(id),
@@ -438,6 +446,7 @@ pub const Command = struct { // MARK: Command
 		depositOrDrop = 7,
 		clear = 8,
 		updateBlock = 9,
+		addHealth = 10,
 	};
 	pub const Payload = union(PayloadType) {
 		open: Open,
@@ -450,6 +459,7 @@ pub const Command = struct { // MARK: Command
 		depositOrDrop: DepositOrDrop,
 		clear: Clear,
 		updateBlock: UpdateBlock,
+		addHealth: AddHealth,
 	};
 
 	const BaseOperationType = enum(u8) {
@@ -458,6 +468,7 @@ pub const Command = struct { // MARK: Command
 		delete = 2,
 		create = 3,
 		useDurability = 4,
+		addHealth = 5,
 	};
 
 	const InventoryAndSlot = struct {
@@ -508,12 +519,20 @@ pub const Command = struct { // MARK: Command
 			durability: u31,
 			previousDurability: u32 = undefined,
 		},
+		addHealth: struct {
+			target: ?*main.server.User,
+			health: f32,
+			cause: main.game.DamageType,
+			previous: f32
+		}
 	};
 
 	const SyncOperationType = enum(u8) {
 		create = 0,
 		delete = 1,
 		useDurability = 2,
+		health = 3,
+		kill = 4,
 	};
 
 	const SyncOperation = union(SyncOperationType) { // MARK: SyncOperation
@@ -531,6 +550,13 @@ pub const Command = struct { // MARK: Command
 			inv: InventoryAndSlot,
 			durability: u32
 		},
+		health: struct {
+			target: ?*main.server.User,
+			health: f32
+		},
+		kill: struct {
+			target: ?*main.server.User
+		},
 
 		pub fn executeFromData(data: []const u8) !void {
 			std.debug.assert(data.len >= 1);
@@ -569,6 +595,12 @@ pub const Command = struct { // MARK: Command
 					}
 					
 					durability.inv.inv.update();
+				},
+				.health => |health| {
+					main.game.Player.super.health = std.math.clamp(main.game.Player.super.health + health.health, 0, main.game.Player.super.maxHealth);
+				},
+				.kill => {
+					main.game.Player.kill();
 				}
 			}
 		}
@@ -577,10 +609,22 @@ pub const Command = struct { // MARK: Command
 			switch (self) {
 				inline .create, .delete, .useDurability => |data| {
 					return allocator.dupe(*main.server.User, Sync.ServerSide.inventories.items[data.inv.inv.id].users.items);
+				},
+				inline .health, .kill => |data| {
+					const out = allocator.alloc(*main.server.User, 1);
+					out[0] = data.target.?;
+					return out;
 				}
 			}
 		}
 
+		pub fn ignoreSource(self: SyncOperation) bool {
+			return switch (self) {
+				.create, .delete, .useDurability, .health => true,
+				.kill => false
+			};
+		}
+
 		fn deserialize(fullData: []const u8) !SyncOperation {
 			if (fullData.len == 0) {
 				return error.Invalid;
@@ -630,6 +674,25 @@ pub const Command = struct { // MARK: Command
 					}};
 
 					return out;
+				},
+				.health => {
+					if (data.len != 4) {
+						return error.Invalid;
+					}
+
+					return .{.health = .{
+						.target = null,
+						.health = @bitCast(std.mem.readInt(u32, data[0..4], .big))
+					}};
+				},
+				.kill => {
+					if (data.len != 0) {
+						return error.Invalid;
+					}
+
+					return .{.kill = .{
+						.target = null,
+					}};
 				}
 			}
 		}
@@ -657,7 +720,11 @@ pub const Command = struct { // MARK: Command
 				.useDurability => |durability| {
 					durability.inv.write(data.addMany(8)[0..8]);
 					std.mem.writeInt(u32, data.addMany(4)[0..4], durability.durability, .big);
-				}
+				},
+				.health => |health| {
+					std.mem.writeInt(u32, data.addMany(4)[0..4], @bitCast(health.health), .big);
+				},
+				.kill => {},
 			}
 			return data.toOwnedSlice();
 		}
@@ -729,6 +796,9 @@ pub const Command = struct { // MARK: Command
 					info.source.ref().item = info.item;
 					info.item.tool.durability = info.previousDurability;
 					info.source.inv.update();
+				},
+				.addHealth => |info| {
+					main.game.Player.super.health = info.previous;
 				}
 			}
 		}
@@ -737,7 +807,7 @@ pub const Command = struct { // MARK: Command
 	fn finalize(self: Command, allocator: NeverFailingAllocator, side: Side, data: []const u8) void {
 		for(self.baseOperations.items) |step| {
 			switch(step) {
-				.move, .swap, .create => {},
+				.move, .swap, .create, .addHealth => {},
 				.delete => |info| {
 					info.item.?.deinit();
 				},
@@ -854,6 +924,30 @@ pub const Command = struct { // MARK: Command
 				self.executeDurabilityUseOperation(allocator, side, info.source, info.durability);
 				info.source.inv.update();
 			},
+			.addHealth => |*info| {
+				if (side == .server) {
+					info.previous = info.target.?.player.health;
+
+					info.target.?.player.health = std.math.clamp(info.target.?.player.health + info.health, 0, info.target.?.player.maxHealth);
+
+					if (info.target.?.player.health <= 0) {
+						info.target.?.player.health = info.target.?.player.maxHealth;
+						info.cause.sendMessage(info.target.?.name);
+
+						self.syncOperations.append(allocator, .{.kill = .{
+							.target = info.target.?
+						}});
+					} else {
+						self.syncOperations.append(allocator, .{.health = .{
+							.target = info.target.?,
+							.health = info.health
+						}});
+					}
+				} else {
+					info.previous = main.game.Player.super.health;
+					main.game.Player.super.health = std.math.clamp(main.game.Player.super.health + info.health, 0, main.game.Player.super.maxHealth);
+				}
+			}
 		}
 		self.baseOperations.append(allocator, op);
 	}
@@ -1497,6 +1591,56 @@ pub const Command = struct { // MARK: Command
 			};
 		}
 	};
+
+	const AddHealth = struct { // MARK: AddHealth
+		target: u32,
+		health: f32,
+		cause: main.game.DamageType,
+
+		pub fn run(self: AddHealth, allocator: NeverFailingAllocator, cmd: *Command, side: Side, _: ?*main.server.User, _: Gamemode) error{serverFailure}!void {
+			var target: ?*main.server.User = null;
+
+			if (side == .server) {
+				const userList = main.server.getUserListAndIncreaseRefCount(main.stackAllocator);
+				defer main.server.freeUserListAndDecreaseRefCount(main.stackAllocator, userList);
+				for (userList) |user| {
+					if (user.id == self.target) {
+						target = user;
+						break;
+					}
+				}
+
+				if (target == null) return error.serverFailure;
+
+				if (target.?.gamemode.raw == .creative) return;
+			} else {
+				if (main.game.Player.gamemode.raw == .creative) return;
+			}
+
+			cmd.executeBaseOperation(allocator, .{.addHealth = .{
+				.target = target,
+				.health = self.health,
+				.cause = self.cause,
+				.previous = if (side == .server) target.?.player.health else main.game.Player.super.health
+			}}, side);
+		}
+
+		fn serialize(self: AddHealth, data: *main.List(u8)) void {
+			std.mem.writeInt(u32, data.addMany(4)[0..4], self.target, .big);
+			std.mem.writeInt(u32, data.addMany(4)[0..4], @bitCast(self.health), .big);
+			data.append(@intFromEnum(self.cause));
+		}
+
+		fn deserialize(data: []const u8, _: Side, _: ?*main.server.User) !AddHealth {
+			if(data.len != 9) return error.Invalid;
+
+			return .{
+				.target = std.mem.readInt(u32, data[0..4], .big),
+				.health = @bitCast(std.mem.readInt(u32, data[4..8], .big)),
+				.cause = @enumFromInt(data[8]),
+			};
+		}
+	};
 };
 
 const SourceType = enum(u8) {

src/game.zig

@@ -326,6 +326,20 @@ pub const collision = struct {
 
 pub const Gamemode = enum(u8) { survival = 0, creative = 1 };
 
+pub const DamageType = enum(u8) {
+	heal = 0, // For when you are adding health
+	kill = 1,
+	fall = 2,
+	
+	pub fn sendMessage(self: DamageType, name: []const u8) void {
+		switch (self) {
+			.heal => main.server.sendMessage("{s}§#ffffff was healed", .{name}),
+			.kill => main.server.sendMessage("{s}§#ffffff was killed", .{name}),
+			.fall => main.server.sendMessage("{s}§#ffffff died of fall damage", .{name}),
+		}
+	}
+};
+
 pub const Player = struct { // MARK: Player
 	pub var super: main.server.Entity = .{};
 	pub var eyePos: Vec3d = .{0, 0, 0};
@@ -341,9 +355,6 @@ pub const Player = struct { // MARK: Player
 	pub var inventory: Inventory = undefined;
 	pub var selectedSlot: u32 = 0;
 
-	pub var maxHealth: f32 = 8;
-	pub var health: f32 = 4.5;
-
 	pub var onGround: bool = false;
 	pub var jumpCooldown: f64 = 0;
 	const jumpCooldownConstant = 0.3;
@@ -442,6 +453,17 @@ pub const Player = struct { // MARK: Player
 		inventory.placeBlock(selectedSlot);
 	}
 
+	pub fn kill() void {
+		Player.super.pos = world.?.spawn;
+		Player.super.vel = .{0, 0, 0};
+
+		Player.super.health = Player.super.maxHealth;
+		
+		Player.eyeVel = .{0, 0, 0};
+		Player.eyeCoyote = 0;
+		Player.eyeStep = .{false, false, false};
+	}
+
 	pub fn breakBlock(deltaTime: f64) void {
 		if(!main.Window.grabbed) return;
 		inventory.breakBlock(selectedSlot, deltaTime);
@@ -955,6 +977,12 @@ pub fn update(deltaTime: f64) void { // MARK: update()
 			} else {
 				Player.super.pos[2] = box.min[2] - hitBox.max[2];
 			}
+
+			const damage: f32 = @floatCast(@round(@max((Player.super.vel[2] * Player.super.vel[2]) / (2 * gravity) - 3, 0)) / 2);
+			if (damage > 0.01) {
+				Inventory.Sync.addHealth(-damage, .fall, .client, Player.id);
+			}
+
 			Player.super.vel[2] = 0;
 
 			// Always unstuck upwards for now

src/gui/windows/healthbar.zig

@@ -47,14 +47,14 @@ pub fn render() void {
 	var y: f32 = 0;
 	var x: f32 = 0;
 	var health: f32 = 0;
-	while(health < main.game.Player.maxHealth) : (health += 1) {
+	while(health < main.game.Player.super.maxHealth) : (health += 1) {
 		if(x >= window.contentSize[0]) {
 			x = 0;
 			y += 20;
 		}
-		if(health + 1 <= main.game.Player.health) {
+		if(health + 1 <= main.game.Player.super.health) {
 			heartTexture.bindTo(0);
-		} else if(health + 0.5 <= main.game.Player.health) {
+		} else if(health + 0.5 <= main.game.Player.super.health) {
 			halfHeartTexture.bindTo(0);
 		} else {
 			deadHeartTexture.bindTo(0);

src/server/Entity.zig

@@ -10,13 +10,17 @@ const NeverFailingAllocator = main.utils.NeverFailingAllocator;
 pos: Vec3d = .{0, 0, 0},
 vel: Vec3d = .{0, 0, 0},
 rot: Vec3f = .{0, 0, 0},
-// TODO: Health and hunger
+
+health: f32 = 8,
+maxHealth: f32 = 8,
+// TODO: Hunger
 // TODO: Name
 
 pub fn loadFrom(self: *@This(), zon: ZonElement) void {
 	self.pos = zon.get(Vec3d, "position", .{0, 0, 0});
 	self.vel = zon.get(Vec3d, "velocity", .{0, 0, 0});
 	self.rot = zon.get(Vec3f, "rotation", .{0, 0, 0});
+	self.health = zon.get(f32, "health", self.maxHealth);
 }
 
 pub fn save(self: *@This(), allocator: NeverFailingAllocator) ZonElement {
@@ -24,5 +28,6 @@ pub fn save(self: *@This(), allocator: NeverFailingAllocator) ZonElement {
 	zon.put("position", self.pos);
 	zon.put("velocity", self.vel);
 	zon.put("rotation", self.rot);
+	zon.put("health", self.health);
 	return zon;
 }

src/server/command/_list.zig

@@ -4,5 +4,6 @@ pub const clear = @import("clear.zig");
 pub const gamemode = @import("gamemode.zig");
 pub const help = @import("help.zig");
 pub const invite = @import("invite.zig");
+pub const kill = @import("kill.zig");
 pub const time = @import("time.zig");
 pub const tp = @import("tp.zig");

src/server/command/kill.zig

@@ -0,0 +1,15 @@
+const std = @import("std");
+
+const main = @import("root");
+const User = main.server.User;
+
+pub const description = "Kills the player";
+pub const usage = "/kill";
+
+pub fn execute(args: []const u8, source: *User) void {
+	if(args.len != 0) {
+		source.sendMessage("#ff0000Too many arguments for command /kill. Expected no arguments.", .{});
+		return;
+	}
+	main.items.Inventory.Sync.addHealth(-std.math.floatMax(f32), .kill, .server, source.id);
+}