feat(trails): render authoritative player route trails

test/host/test_game_core.c

@@ -324,12 +324,48 @@ static void test_default_map_chunk_bounds(void) {
            (unsigned int)chunks, (unsigned int)largest_chunk);
 }
 
+static void test_authoritative_trails_and_visibility(void) {
+    maze32_maze_t maze;
+    open_test_grid(&maze);
+    maze.starts[1] = (maze32_cell_t){2U, 1U};
+    maze32_game_t game = initialized_game(&maze);
+    maze32_game_set_phase(&game, MAZE32_GAME_PHASE_ACTIVE);
+    uint32_t sequence = 0U;
+    assert(maze32_game_enqueue_move(&game, MAZE32_GAME_ROLE_PLAYER_ONE, MAZE32_GAME_DIRECTION_EAST,
+                                    200U, &sequence) == MAZE32_GAME_RESULT_ACCEPTED);
+    assert(maze32_game_process_next(&game).result == MAZE32_GAME_RESULT_ACCEPTED);
+    assert(maze32_game_enqueue_move(&game, MAZE32_GAME_ROLE_PLAYER_TWO, MAZE32_GAME_DIRECTION_WEST,
+                                    200U, &sequence) == MAZE32_GAME_RESULT_ACCEPTED);
+    assert(maze32_game_process_next(&game).result == MAZE32_GAME_RESULT_ACCEPTED);
+
+    maze32_view_t observer;
+    assert(maze32_game_project_view(&game, MAZE32_GAME_ROLE_OBSERVER, &observer) ==
+           MAZE32_GAME_RESULT_ACCEPTED);
+    uint16_t origin = index_of(1U, 1U);
+    int found = 0;
+    for (uint16_t index = 0U; index < observer.cell_count; ++index) {
+        if (observer.cells[index].cell_index == origin) {
+            assert(observer.cells[index].trail_east == 3U);
+            found = 1;
+        }
+    }
+    assert(found);
+    maze32_view_t player;
+    assert(maze32_game_project_view(&game, MAZE32_GAME_ROLE_PLAYER_ONE, &player) ==
+           MAZE32_GAME_RESULT_ACCEPTED);
+    for (uint16_t index = 0U; index < player.cell_count; ++index) {
+        assert(player.cells[index].trail_east <= 3U && player.cells[index].trail_south <= 3U);
+    }
+    puts("authoritative trail ownership and visibility: PASS");
+}
+
 int main(void) {
     test_movement_cooldown_and_ordering();
     test_bounded_queue();
     test_shared_cell_meeting();
     test_visibility_and_serialization();
     test_default_map_chunk_bounds();
+    test_authoritative_trails_and_visibility();
     puts("game core tests: PASS");
     return 0;
 }