Add tracerestrict reserved tiles ahead conditional

src/lang/english.txt

@@ -2784,6 +2784,7 @@ STR_TRACE_RESTRICT_VARIABLE_SLOT_OCCUPANCY_SHORT                :occupancy
 STR_TRACE_RESTRICT_VARIABLE_SLOT_OCCUPANCY_REMAINING_SHORT      :occupancy remaining
 STR_TRACE_RESTRICT_VARIABLE_COUNTER_VALUE                       :counter value
 STR_TRACE_RESTRICT_VARIABLE_TIME_DATE_VALUE                     :current time/date
+STR_TRACE_RESTRICT_VARIABLE_RESERVED_TILES_AHEAD                :reserved tiles ahead
 STR_TRACE_RESTRICT_VARIABLE_TRAIN_WEIGHT                        :weight
 STR_TRACE_RESTRICT_VARIABLE_TRAIN_POWER                         :power
 STR_TRACE_RESTRICT_VARIABLE_TRAIN_MAX_TE                        :max T.E.

src/saveload/extended_ver_sl.cpp

@@ -76,7 +76,7 @@ const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_TRACE_RESTRICT_NEWSCTRL,XSCF_NULL,                1,   1, "tracerestrict_newsctrl",    nullptr, nullptr, nullptr        },
 	{ XSLFI_TRACE_RESTRICT_COUNTER, XSCF_NULL,                1,   1, "tracerestrict_counter",     nullptr, nullptr, "TRRC"         },
 	{ XSLFI_TRACE_RESTRICT_TIMEDATE,XSCF_NULL,                1,   1, "tracerestrict_timedate",    nullptr, nullptr, nullptr        },
-	{ XSLFI_TRACE_RESTRICT_BRKCND,  XSCF_NULL,                1,   1, "tracerestrict_braking_cond",nullptr, nullptr, nullptr        },
+	{ XSLFI_TRACE_RESTRICT_BRKCND,  XSCF_NULL,                2,   2, "tracerestrict_braking_cond",nullptr, nullptr, nullptr        },
 	{ XSLFI_PROG_SIGS,              XSCF_NULL,                2,   2, "programmable_signals",      nullptr, nullptr, "SPRG"      },
 	{ XSLFI_ADJACENT_CROSSINGS,     XSCF_NULL,                1,   1, "adjacent_crossings",        nullptr, nullptr, nullptr        },
 	{ XSLFI_SAFER_CROSSINGS,        XSCF_NULL,                1,   1, "safer_crossings",           nullptr, nullptr, nullptr        },

src/tracerestrict.cpp

@@ -524,6 +524,15 @@ void TraceRestrictProgram::Execute(const Train* v, const TraceRestrictProgramInp
 						break;
 					}
 
+					case TRIT_COND_RESERVED_TILES: {
+						uint tiles_ahead = 0;
+						if (v->lookahead != nullptr) {
+							tiles_ahead = std::max<int>(0, v->lookahead->reservation_end_position - v->lookahead->current_position) / TILE_SIZE;
+						}
+						result = TestCondition(tiles_ahead, condop, condvalue);
+						break;
+					}
+
 					default:
 						NOT_REACHED();
 				}
@@ -807,6 +816,7 @@ CommandCost TraceRestrictProgram::Validate(const std::vector<TraceRestrictItem>
 				case TRIT_COND_LOAD_PERCENT:
 				case TRIT_COND_COUNTER_VALUE:
 				case TRIT_COND_TIME_DATE_VALUE:
+				case TRIT_COND_RESERVED_TILES:
 					break;
 
 				default:

src/tracerestrict.h

@@ -151,6 +151,7 @@ enum TraceRestrictItemType {
 	TRIT_COND_LOAD_PERCENT        = 26,   ///< Test train load percentage
 	TRIT_COND_COUNTER_VALUE       = 27,   ///< Test counter value
 	TRIT_COND_TIME_DATE_VALUE     = 28,   ///< Test time/date value
+	TRIT_COND_RESERVED_TILES      = 29,   ///< Test reserved tiles ahead of train
 
 	TRIT_COND_END                 = 48,   ///< End (exclusive) of conditional item types, note that this has the same value as TRIT_REVERSE
 	TRIT_REVERSE                  = 48,   ///< Reverse behind signal
@@ -753,6 +754,10 @@ static inline TraceRestrictTypePropertySet GetTraceRestrictTypeProperties(TraceR
 				out.value_type = TRVT_TIME_DATE_INT;
 				break;
 
+			case TRIT_COND_RESERVED_TILES:
+				out.value_type = TRVT_INT;
+				break;
+
 			default:
 				NOT_REACHED();
 				break;

src/tracerestrict_gui.cpp

@@ -458,6 +458,7 @@ static const TraceRestrictDropDownListSet *GetTypeDropDownListSet(TraceRestrictG
 		STR_TRACE_RESTRICT_VARIABLE_SLOT_OCCUPANCY_REMAINING,
 		STR_TRACE_RESTRICT_VARIABLE_COUNTER_VALUE,
 		STR_TRACE_RESTRICT_VARIABLE_TIME_DATE_VALUE,
+		STR_TRACE_RESTRICT_VARIABLE_RESERVED_TILES_AHEAD,
 		STR_TRACE_RESTRICT_VARIABLE_UNDEFINED,
 		INVALID_STRING_ID,
 	};
@@ -485,6 +486,7 @@ static const TraceRestrictDropDownListSet *GetTypeDropDownListSet(TraceRestrictG
 		TRIT_COND_SLOT_OCCUPANCY | (TRSOCAF_REMAINING << 16),
 		TRIT_COND_COUNTER_VALUE,
 		TRIT_COND_TIME_DATE_VALUE,
+		TRIT_COND_RESERVED_TILES,
 		TRIT_COND_UNDEFINED,
 	};
 	static const TraceRestrictDropDownListSet set_cond = {
@@ -496,10 +498,10 @@ static const TraceRestrictDropDownListSet *GetTypeDropDownListSet(TraceRestrictG
 		if (_settings_client.gui.show_adv_tracerestrict_features) {
 			*hide_mask = 0;
 		} else {
-			*hide_mask = is_conditional ? 0x7C0000 : 0x2F0;
+			*hide_mask = is_conditional ? 0xFC0000 : 0x2F0;
 		}
 		if (is_conditional && !_settings_game.game_time.time_in_minutes) *hide_mask |= 0x400000;
-		if (is_conditional && _settings_game.vehicle.train_braking_model != TBM_REALISTIC) *hide_mask |= 0x200;
+		if (is_conditional && _settings_game.vehicle.train_braking_model != TBM_REALISTIC) *hide_mask |= 0x800200;
 	}
 	return is_conditional ? &set_cond : &set_action;
 }