Add new landscape flag to enable drawing rocks covered by snow

docs/newgrf-newlandscape-nml.html

@@ -64,6 +64,12 @@
 				</table>
 			</td>
 		</tr>
+		<tr><td>enable_draw_snowy_rocks</td><td>0 or 1</td>
+			<td>
+				Enable drawing of rock tiles covered by snow, for this GRF.<br />
+				(This only takes effect from <font face="monospace">new_landscape</font> version 2).
+			</td>
+		</tr>
 	</table>
 
 	<h3 id="newlandscape_variables">New Landscape Variables</h3>

docs/newgrf-newlandscape.html

@@ -48,6 +48,7 @@
 	<table>
 		<tr><th>Mappable name</th><th>Size in bytes</th><th>Description</th></tr>
 		<tr><td><a href="#newlandscape_enable_recolour">newlandscape_enable_recolour</a></td><td>1</td><td>Enable recolour</td></tr>
+		<tr><td><a href="#newlandscape_enable_draw_snowy_rocks">newlandscape_enable_draw_snowy_rocks</a></td><td>1</td><td>Enable drawing rocky tiles covered by snow</td></tr>
 	</table>
 
 	<h4 id="newlandscape_enable_recolour">Enable recolouring for new landscape graphics (mappable property: newlandscape_enable_recolour)</h4>
@@ -59,6 +60,11 @@
 	</table></p>
 	<p>The property length is 1 byte. 0 is disabled (default). 1 is enabled.</p>
 
+	<h4 id="newlandscape_enable_draw_snowy_rocks">Enable drawing rocky tiles covered by snow (mappable property: newlandscape_enable_draw_snowy_rocks)</h4>
+	<p>When enabled, drawing of rocky tiles covered by snow is enabled for this GRF.</p>
+	<p>The property length is 1 byte. 0 is disabled (default). 1 is enabled.<br />
+	This requires <font face="monospace">new_landscape</font>, version 2.</p>
+
 	<h3 id="a2roadstops">Action 2 - New Landscape</h3>
 
 	<p>See the <a href="https://newgrf-specs.tt-wiki.net/wiki/Action2">Action 2 Specification</a> for background information.</p>

src/clear_cmd.cpp

@@ -81,22 +81,22 @@ inline SpriteID GetSpriteIDForRocksUsingOffset(const uint slope_to_sprite_offset
 	return ((HasGrfMiscBit(GMB_SECOND_ROCKY_TILE_SET) && (TileHash(x, y) & 1)) ? SPR_FLAT_ROCKY_LAND_2 : SPR_FLAT_ROCKY_LAND_1) + slope_to_sprite_offset;
 }
 
-void DrawCustomSpriteIDForRocks(const TileInfo *ti)
+bool DrawCustomSpriteIDForRocks(const TileInfo *ti, uint8 slope_to_sprite_offset, bool require_snow_flag)
 {
-	uint8 slope_to_sprite_offset = SlopeToSpriteOffset(ti->tileh);
-
 	for (const GRFFile *grf : _new_landscape_rocks_grfs) {
+		if (require_snow_flag && !HasBit(grf->new_landscape_ctrl_flags, NLCF_ROCKS_DRAW_SNOWY_ENABLED)) continue;
+
 		NewLandscapeResolverObject object(grf, ti, NEW_LANDSCAPE_ROCKS);
 
 		const SpriteGroup *group = object.Resolve();
 		if (group != nullptr && group->GetNumResults() > slope_to_sprite_offset) {
 			PaletteID pal = HasBit(grf->new_landscape_ctrl_flags, NLCF_ROCKS_RECOLOUR_ENABLED) ? GB(GetRegister(0x100), 0, 24) : PAL_NONE;
 			DrawGroundSprite(group->GetResult() + slope_to_sprite_offset, pal);
-			return;
+			return true;
 		}
 	}
 
-	DrawGroundSprite(GetSpriteIDForRocksUsingOffset(slope_to_sprite_offset, ti->x, ti->y), PAL_NONE);
+	return false;
 }
 
 SpriteID GetSpriteIDForFields(const Slope slope, const uint field_type)
@@ -104,6 +104,11 @@ SpriteID GetSpriteIDForFields(const Slope slope, const uint field_type)
 	return _clear_land_sprites_farmland[field_type] + SlopeToSpriteOffset(slope);
 }
 
+inline SpriteID GetSpriteIDForSnowDesertUsingOffset(const uint slope_to_sprite_offset, const uint density)
+{
+	return _clear_land_sprites_snow_desert[density] + slope_to_sprite_offset;
+}
+
 SpriteID GetSpriteIDForSnowDesert(const Slope slope, const uint density)
 {
 	return _clear_land_sprites_snow_desert[density] + SlopeToSpriteOffset(slope);
@@ -162,7 +167,9 @@ static void DrawTile_Clear(TileInfo *ti, DrawTileProcParams params)
 
 		case CLEAR_ROCKS:
 			if (!params.no_ground_tiles) {
-				DrawCustomSpriteIDForRocks(ti);
+				uint8 slope_to_sprite_offset = SlopeToSpriteOffset(ti->tileh);
+				if (DrawCustomSpriteIDForRocks(ti, slope_to_sprite_offset, false)) break;
+				DrawGroundSprite(GetSpriteIDForRocksUsingOffset(slope_to_sprite_offset, ti->x, ti->y), PAL_NONE);
 			}
 			break;
 
@@ -174,6 +181,15 @@ static void DrawTile_Clear(TileInfo *ti, DrawTileProcParams params)
 			break;
 
 		case CLEAR_SNOW:
+			if (!params.no_ground_tiles) {
+				uint8 slope_to_sprite_offset = SlopeToSpriteOffset(ti->tileh);
+				if (GetRawClearGround(ti->tile) == CLEAR_ROCKS && !_new_landscape_rocks_grfs.empty()) {
+					if (DrawCustomSpriteIDForRocks(ti, slope_to_sprite_offset, true)) break;
+				}
+				DrawGroundSprite(GetSpriteIDForSnowDesertUsingOffset(slope_to_sprite_offset, GetClearDensity(ti->tile)), PAL_NONE);
+			}
+			break;
+
 		case CLEAR_DESERT:
 			if (!params.no_ground_tiles) DrawGroundSprite(GetSpriteIDForSnowDesert(ti->tileh, GetClearDensity(ti->tile)), PAL_NONE);
 			break;

src/newgrf.cpp

@@ -5183,6 +5183,15 @@ static ChangeInfoResult NewLandscapeChangeInfo(uint id, int numinfo, int prop, c
 				break;
 			}
 
+			case A0RPI_NEWLANDSCAPE_ENABLE_DRAW_SNOWY_ROCKS: {
+				if (MappedPropertyLengthMismatch(buf, 1, mapping_entry)) break;
+				bool enabled = (buf->ReadByte() != 0 ? 1 : 0);
+				if (id == NLA3ID_CUSTOM_ROCKS) {
+					SB(_cur.grffile->new_landscape_ctrl_flags, NLCF_ROCKS_DRAW_SNOWY_ENABLED, 1, enabled);
+				}
+				break;
+			}
+
 			default:
 				ret = HandleAction0PropertyDefault(buf, prop);
 				break;

src/newgrf.h

@@ -286,8 +286,9 @@ enum NewSignalAction3ID {
 
 /** New landscape control flags. */
 enum NewLandscapeCtrlFlags {
-	NLCF_ROCKS_SET              = 0,                          ///< Custom landscape rocks sprites group set.
+	NLCF_ROCKS_SET                = 0,                        ///< Custom landscape rocks sprites group set.
-	NLCF_ROCKS_RECOLOUR_ENABLED = 1,                          ///< Recolour sprites enabled for rocks
+	NLCF_ROCKS_RECOLOUR_ENABLED   = 1,                        ///< Recolour sprites enabled for rocks
+	NLCF_ROCKS_DRAW_SNOWY_ENABLED = 2,                        ///< Enable drawing rock tiles on snow
 };
 
 /** New landscape action 3 IDs. */

src/newgrf_debug_gui.cpp

@@ -1172,7 +1172,7 @@ GrfSpecFeature GetGrfSpecFeature(TileIndex tile)
 	switch (GetTileType(tile)) {
 		default:              return GSF_INVALID;
 		case MP_CLEAR:
-			if (IsClearGround(tile, CLEAR_ROCKS)) return GSF_NEWLANDSCAPE;
+			if (GetRawClearGround(tile) == CLEAR_ROCKS) return GSF_NEWLANDSCAPE;
 			return GSF_INVALID;
 		case MP_RAILWAY: {
 			extern std::vector<const GRFFile *> _new_signals_grfs;

src/newgrf_extension.cpp

@@ -56,7 +56,7 @@ extern const GRFFeatureInfo _grf_feature_list[] = {
 	GRFFeatureInfo("action0_object_flood_resistant", 1),
 	GRFFeatureInfo("action0_object_viewport_map_tile_type", 1),
 	GRFFeatureInfo("road_stops", 4),
-	GRFFeatureInfo("new_landscape", 1),
+	GRFFeatureInfo("new_landscape", 2),
 	GRFFeatureInfo(),
 };
 
@@ -125,6 +125,7 @@ extern const GRFPropertyMapDefinition _grf_action0_remappable_properties[] = {
 	GRFPropertyMapDefinition(GSF_ROADSTOPS, A0RPI_ROADSTOP_DISALLOWED_BRIDGE_PILLARS, "roadstop_disallowed_bridge_pillars"),
 	GRFPropertyMapDefinition(GSF_ROADSTOPS, A0RPI_ROADSTOP_COST_MULTIPLIERS, "roadstop_cost_multipliers"),
 	GRFPropertyMapDefinition(GSF_NEWLANDSCAPE, A0RPI_NEWLANDSCAPE_ENABLE_RECOLOUR, "newlandscape_enable_recolour"),
+	GRFPropertyMapDefinition(GSF_NEWLANDSCAPE, A0RPI_NEWLANDSCAPE_ENABLE_DRAW_SNOWY_ROCKS, "newlandscape_enable_draw_snowy_rocks"),
 	GRFPropertyMapDefinition(),
 };
 

src/newgrf_extension.h

@@ -68,6 +68,7 @@ enum Action0RemapPropertyIds {
 	A0RPI_ROADSTOP_DISALLOWED_BRIDGE_PILLARS,
 	A0RPI_ROADSTOP_COST_MULTIPLIERS,
 	A0RPI_NEWLANDSCAPE_ENABLE_RECOLOUR,
+	A0RPI_NEWLANDSCAPE_ENABLE_DRAW_SNOWY_ROCKS,
 };