implement entities

Signed-off-by: Lizzy Fleckenstein <lizzy@vlhl.dev>

1 files changed, 154 insertions, 33 deletions

diff --git a/src/server.c b/src/server.c
index 974e396..108ae0d 100644
--- a/src/server.c
+++ b/src/server.c
@@ -44,8 +44,7 @@ typedef struct {
 	bool auth;
 	str name;
 	entity_id id;
-	vec2 pos;
-	int8_t z;
+	int8_t z; // TODO: move to entity
 	peer conn;
 } player;
 
@@ -55,9 +54,109 @@ typedef struct {
 	str passphrase;
 	array(map) maps;
 	arraybuf(player) players;
+	arraybuf(entity) entities;
 	entity_id next_entity;
 } game;
 
+player *player_from_id(game *g, entity_id id)
+{
+	for (size_t i = 0; i < g->players.len; i++)
+		if (g->players.data[i].id == id)
+			return &g->players.data[i];
+	return NULL;
+}
+
+entity *entity_from_id(game *g, entity_id id)
+{
+	for (size_t i = 0; i < g->entities.len; i++)
+		if (g->entities.data[i].id == id)
+			return &g->entities.data[i];
+	return NULL;
+}
+
+box2 player_sight(vec2 center)
+{
+	return box2_around(center, SIGHT_RANGE);
+}
+
+void ser_entity_update(strbuf *w, entity *e, entity_cmd cmd)
+{
+	ser_entity_id(w, e->id);
+	ser_entity_cmd(w, cmd);
+
+	switch (cmd) {
+		case ENTITY_ADD:
+			ser_entity_type(w, e->type);
+			ser_vec2(w, e->pos);
+			switch (e->type) {
+				case ENTITY_FLOWER:
+					ser_flower_type(w, e->flower);
+					break;
+				default: break;
+			}
+			break;
+		case ENTITY_MOVE:
+			ser_vec2(w, e->pos);
+			break;
+		case ENTITY_REMOVE:
+			break;
+		case ENTITY_CMD_COUNT:
+			break; // unreachable
+	}
+}
+
+static vec2 *moved_get_pos(entity *e, entity *moved, vec2 *p_moved)
+{
+	return (e == moved) ? p_moved : &e->pos;
+}
+
+static bool moved_can_see(entity *a, entity *b, entity *moved, vec2 *p_moved)
+{
+	vec2 *p_a = moved_get_pos(a, moved, p_moved);
+	vec2 *p_b = moved_get_pos(b, moved, p_moved);
+	return p_a && p_b && box2_contains(player_sight(*p_a), *p_b);
+}
+
+static entity_cmd moved_check_update(entity *observer, entity *target, entity *moved, vec2 *before, vec2 *after)
+{
+	bool see_before = moved_can_see(observer, target, moved, before);
+	bool see_after = moved_can_see(observer, target, moved, after);
+
+	if (see_before && !see_after)
+		return ENTITY_REMOVE;
+	else if (!see_before && see_after)
+		return ENTITY_ADD;
+	else if (see_before && see_after && target == moved)
+		return ENTITY_MOVE;
+	else
+		return ENTITY_CMD_COUNT;
+}
+
+void moved_entity(game *g, entity *moved, vec2 *before, vec2 *after)
+{
+	for (size_t i = 0; i < g->players.len; i++) {
+		player *p = &g->players.data[i];
+		if (!p->auth) continue;
+
+		entity *observer = entity_from_id(g, p->id);
+
+		if (observer == moved) {
+			SEND_PKT(p->conn, CPKT_ENTITY,
+				for (size_t j = 0; j < g->entities.len; j++) {
+					entity *target = &g->entities.data[j];
+					entity_cmd cmd = moved_check_update(observer, target, moved, before, after);
+					if (cmd != ENTITY_CMD_COUNT)
+						ser_entity_update(&pkt, target, cmd);
+				}
+			)
+		} else {
+			entity_cmd cmd = moved_check_update(observer, moved, moved, before, after);
+			if (cmd != ENTITY_CMD_COUNT)
+				SEND_PKT(p->conn, CPKT_ENTITY, ser_entity_update(&pkt, moved, cmd);)
+		}
+	}
+}
+
 node *map_node(game *g, vec2 p, int8_t z)
 {
 	for (size_t i = 0; i < g->maps.len; i++) {
@@ -84,10 +183,24 @@ bool silly_noise(vec2 pos, uint32_t grid, double sillyness, int seed)
 	y += round(noise2d(y/grid, x/grid, 0, seed) * sillyness);
 
 	return x % grid == 0 && y % grid == 0;
-#undef SMOD
 }
 
-void map_load_node(map *m, uvec2 v, color col)
+entity *spawn_entity(game *g, entity_type type, vec2 pos)
+{
+	entity *e = ARR_APPEND(g->entities);
+	e->id = g->next_entity++;
+	e->type = type;
+	e->pos = pos;
+	return e;
+}
+
+void remove_entity(game *g, entity *e)
+{
+	moved_entity(g, e, &e->pos, NULL);
+	ARR_REMOVE(g->entities, e);
+}
+
+void map_load_node(game *g, map *m, uvec2 v, color col)
 {
 	uint32_t ucol = color_to_u32(col);
 
@@ -101,20 +214,21 @@ void map_load_node(map *m, uvec2 v, color col)
 		return;
 
 	switch (ucol) {
+		case 0xff9de2:
+			spawn_entity(g, ENTITY_FLOWER, pos)->flower = rand() % FLOWER_COUNT;
+			[[fallthrough]];
 		case 0x00880d: n->type = N_GRASS;
 			n->variant = silly_noise(pos, 3, 1.0, 0);
 			break;
 		case 0x595959: n->type = N_ROCK; n->z = 1; break;
+		case 0x001b51:
+			spawn_entity(g, ENTITY_FLOWER, pos)->flower = FLOWER_DANDELION;
+			[[fallthrough]];
 		case 0x484848: n->type = N_ROCK; n->z = 2; break;
+		case 0x00ffe8:
+			spawn_entity(g, ENTITY_FLOWER, pos)->flower = FLOWER_DANDELION;
+			[[fallthrough]];
 		case 0x373737: n->type = N_ROCK; n->z = 3; break;
-		case 0x00ffe8: n->type = N_MOUNTAIN_FLOWER;
-			n->variant = FLOWER_DANDELION;
-			n->z = 3;
-			break;
-		case 0x001b51: n->type = N_MOUNTAIN_FLOWER;
-			n->variant = FLOWER_DANDELION;
-			n->z = 2;
-			break;
 		case 0xa09700: n->type = N_PATH; break;
 		case 0x015100: n->type = N_NEEDLE_TREE; break;
 		case 0x00c6ff: n->type = N_WATER;
@@ -122,9 +236,6 @@ void map_load_node(map *m, uvec2 v, color col)
 			n->z = -1;
 			break;
 		case 0x5c3b12: n->type = N_PLANK; break;
-		case 0xff9de2: n->type = N_VALLEY_FLOWER;
-			n->variant = rand() % FLOWER_COUNT;
-			break;
 		case 0x016300: n->type = N_BIG_TREE; break;
 		case 0xfce84e: n->type = N_SAND;
 			n->variant = silly_noise(pos, 4, 1.0, 1);
@@ -137,7 +248,7 @@ void map_load_node(map *m, uvec2 v, color col)
 	}
 }
 
-bool map_load(map *m)
+bool map_load(game *g, map *m)
 {
 #define TRY(expr, ...) if (!(expr)) { \
 	fprintf(stderr, __VA_ARGS__); \
@@ -188,7 +299,7 @@ bool map_load(map *m)
 				}
 			}*/
 
-			map_load_node(m, UVEC2(x, y), (color) { p[0], p[1], p[2] });
+			map_load_node(g, m, UVEC2(x, y), (color) { p[0], p[1], p[2] });
 		}
 	}
 
@@ -225,7 +336,7 @@ void send_nodes(player *p, game *g, box2 bounds, int8_t z)
 	)
 }
 
-void player_free(player *p)
+void player_cleanup(player *p)
 {
 	peer_free(&p->conn);
 	if (p->auth)
@@ -234,11 +345,17 @@ void player_free(player *p)
 
 void player_remove(player *p, game *g)
 {
-	player_free(p);
+	player_cleanup(p);
 
 	bool auth = p->auth;
+    entity_id id = p->id;
+
 	ARR_REMOVE(g->players, p);
-	if (auth) send_players(g);
+
+	if (auth) {
+		remove_entity(g, entity_from_id(g, id));
+		send_players(g);
+	}
 }
 
 void game_exit(game *g, int ret)
@@ -253,7 +370,7 @@ void game_exit(game *g, int ret)
 	free(g->maps.data);
 
 	for (size_t i = 0; i < g->players.len; i++)
-		player_free(&g->players.data[i]);
+		player_cleanup(&g->players.data[i]);
 	free(g->players.data);
 
 	exit(ret);
@@ -283,18 +400,23 @@ bool handle_hi(str pkt, player *p, game *g)
 
 	p->auth = true;
 	p->name = str_clone(name);
-	p->pos.x = p->pos.y = 0;
+
+	entity *e = ARR_APPEND(g->entities);
+	e->id = p->id;
+	e->type = ENTITY_PLAYER;
+	e->pos.x = e->pos.y = 0;
 	p->z = 0;
 
 	SEND_PKT(p->conn, CPKT_HI, ser_str(&pkt, g->motd);)
 	send_players(g);
 
-	send_nodes(p, g, box2_around(p->pos, SIGHT_RANGE), p->z);
+	moved_entity(g, e, NULL, &e->pos);
+	send_nodes(p, g, player_sight(e->pos), p->z);
 
 	return true;
 }
 
-bool handle_move(str pkt, player *p, [[maybe_unused]] game *g)
+bool handle_move(str pkt, player *p, game *g)
 {
 	dir d;
 	if (!deser_dir(&pkt, &d)) return false;
@@ -303,17 +425,16 @@ bool handle_move(str pkt, player *p, [[maybe_unused]] game *g)
 	if (vec2_iszero(v))
 		return false;
 
+	entity *e = entity_from_id(g, p->id);
+
 	// yolo
-	p->pos = vec2_add(v, p->pos);
-	SEND_PKT(p->conn, CPKT_ENTITY,
-		ser_u16(&pkt, 1);
-		ser_entity_id(&pkt, p->id);
-		ser_entity_cmd(&pkt, ENTITY_MOVE);
-		ser_vec2(&pkt, p->pos);
-	)
+	vec2 old_pos = e->pos;
+	e->pos = vec2_add(v, e->pos);
+
+	moved_entity(g, e, &old_pos, &e->pos);
 
 	// TODO: only send newly visible nodes
-	send_nodes(p, g, box2_around(p->pos, SIGHT_RANGE), p->z);
+	send_nodes(p, g, player_sight(e->pos), p->z);
 
 	return true;
 }
@@ -355,7 +476,7 @@ int main()
 		.chunk = chunk_alloc((box2) { { -50, -50 }, { 100, 100 } }),
 	};
 
-	if (!map_load(&g.maps.data[0]))
+	if (!map_load(&g, &g.maps.data[0]))
 		game_exit(&g, EXIT_FAILURE);
 
 	if ((g.accept_fd = socket_create("0.0.0.0", "4560", true)) < 0)