added raylib, enet

src/shared/protocol.zig

@@ -1,15 +1,70 @@
 const std = @import("std");
+const entity = @import("entity.zig");
+const zm = @import("zmath");
 
 pub const SERVER_PORT: u16 = 1337;
 
+pub const MessageType = enum(u8) {
+    spawn_entity = 1,
+    // later: despawn_entity, update_entity, snapshot, etc.
+};
+
+pub const SpawnEntity = struct {
+    id: entity.entity_id,
+    kind: EntityKind,
+    payload: []const u8, // serialized entity data
+};
+
+pub fn write_message(writer: *std.Io.Writer, msg_type: MessageType, payload: []const u8) !void {
+    try writer.writeByte(@intFromEnum(msg_type));
+    try writer.writeInt(u32, @intCast(payload.len), .little);
+    try writer.writeAll(payload);
+}
+
+pub fn read_message(reader: *std.Io.Reader, allocator: std.mem.Allocator) !struct {
+    msg_type: MessageType,
+    payload: []u8,
+} {
+    const msg_type = try reader.readByte();
+    const size = try reader.readInt(u32, .little);
+
+    const payload = try allocator.alloc(u8, size);
+    errdefer allocator.free(payload);
+
+    try reader.readNoEof(payload);
+
+    return .{
+        .msg_type = @enumFromInt(msg_type),
+        .payload = payload,
+    };
+}
+
+pub const EntityKind = enum(u8) {
+    Player,
+    Monster,
+    Projectile,
+};
+
 pub const Hello = struct {
     msg: []const u8,
 };
 
 pub fn sendHello(writer: *std.io.Writer, hello: Hello) !void {
     try writer.print("{s}\n", .{hello.msg});
+    try writer.flush();
 }
 
-pub fn recvLine(reader: *std.io.Reader) ![]u8 {
-    return try reader.takeDelimiterExclusive('\n');
+fn writeVec4(w: *std.Io.Writer, v: zm.Vec4) !void {
+    const a = zm.vecToArray(v);
+    inline for (a) |f| {
+        try w.writeFloat(f32, f, .little);
+    }
+}
+
+fn readVec4(r: *std.Io.Reader) !zm.Vec4 {
+    var a: [4]f32 = undefined;
+    inline for (&a) |*f| {
+        f.* = try r.readFloat(f32, .little);
+    }
+    return zm.loadArr4(a);
 }