From bd1115e7ff9a6930cff71be4e245bb898b5bbfa0 Mon Sep 17 00:00:00 2001 From: skidd13 Date: Wed, 30 Jan 2008 17:31:39 +0000 Subject: (svn r12021) -Cleanup: Make some parts of the town growth a bit more descriptive -Codechange: Remove some needless checks --- src/town_cmd.cpp | 62 +++++++++++++++++++++++--------------------------------- 1 file changed, 25 insertions(+), 37 deletions(-) diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp index fa579dc59..f57916ea1 100644 --- a/src/town_cmd.cpp +++ b/src/town_cmd.cpp @@ -673,25 +673,25 @@ static RoadBits GetTownRoadBits(TileIndex tile) * @return true if one of the neighboring tiles at the * given distance is a road tile else false */ -static bool IsNeighborRoadTile(TileIndex tile, DiagDirection dir, uint dist_multi) +static bool IsNeighborRoadTile(TileIndex tile, const DiagDirection dir, uint dist_multi) { - static TileIndexDiff tid_lt[3]; // lookup table for the used diff values - tid_lt[0] = TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90RIGHT)); - tid_lt[1] = TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90LEFT)); - tid_lt[2] = TileOffsByDiagDir(ReverseDiagDir(dir)); + /* Lookup table for the used diff values */ + const TileIndexDiff tid_lt[3] = { + TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90RIGHT)), + TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90LEFT)), + TileOffsByDiagDir(ReverseDiagDir(dir)), + }; /* We add 1 to the distance because we want to get 1 for * the min distance multiplyer and not 0. * Therefore we start at 4. The 4 is used because - * there are 4 tiles per distance step to check. - */ + * there are 4 tiles per distance step to check. */ dist_multi = (dist_multi + 1) * 4; for (uint pos = 4; pos < dist_multi; pos++) { TileIndexDiff cur = 0; /* For each even value of pos add the right TileIndexDiff * for each uneven value the left TileIndexDiff - * for each with 2nd bit set (2,3,6,7,..) add the reversed TileIndexDiff - */ + * for each with 2nd bit set (2,3,6,7,..) add the reversed TileIndexDiff */ cur += tid_lt[(pos & 1) ? 0 : 1]; if (pos & 2) cur += tid_lt[2]; @@ -710,19 +710,15 @@ static bool IsNeighborRoadTile(TileIndex tile, DiagDirection dir, uint dist_mult */ static bool IsRoadAllowedHere(TileIndex tile, DiagDirection dir) { - if (TileX(tile) < 2 || TileY(tile) < 2 || MapMaxX() <= TileX(tile) || MapMaxY() <= TileY(tile)) return false; + if (TileX(tile) < 2 || TileX(tile) >= MapMaxX() || TileY(tile) < 2 || TileY(tile) >= MapMaxY()) return false; Slope cur_slope, desired_slope; - /* If this assertion fails, it might be because the world contains - * land at the edges. This is not ok. */ - TILE_ASSERT(tile); - for (;;) { /* Check if there already is a road at this point? */ if (GetTownRoadBits(tile) == ROAD_NONE) { - /* No, try to build one in the direction. - * if that fails clear the land, and if that fails exit. + /* No, try if we are able to build a road piece there. + * If that fails clear the land, and if that fails exit. * This is to make sure that we can build a road here later. */ if (CmdFailed(DoCommand(tile, ((dir == DIAGDIR_NW || dir == DIAGDIR_SE) ? ROAD_X : ROAD_Y), 0, DC_AUTO, CMD_BUILD_ROAD)) && CmdFailed(DoCommand(tile, 0, 0, DC_AUTO, CMD_LANDSCAPE_CLEAR))) @@ -736,10 +732,10 @@ no_slope: switch (_patches.town_layout) { default: NOT_REACHED(); - case TL_ORIGINAL: /* Disallow the road if any neighboring tile has a road (distance: 1) */ + case TL_ORIGINAL: // Disallow the road if any neighboring tile has a road (distance: 1) return !IsNeighborRoadTile(tile, dir, 1); - case TL_BETTER_ROADS: /* Disallow the road if any neighboring tile has a road (distance: 1 and 2). */ + case TL_BETTER_ROADS: // Disallow the road if any neighboring tile has a road (distance: 1 and 2). return !IsNeighborRoadTile(tile, dir, 2); } } @@ -751,8 +747,8 @@ no_slope: if (Chance16(1, 8)) { CommandCost res = CMD_ERROR; if (!_generating_world && Chance16(1, 10)) { - /* Note: Do not replace " ^ 0xF" with ComplementSlope(). The slope might be steep. */ - res = DoCommand(tile, Chance16(1, 16) ? cur_slope : cur_slope ^ 0xF, 0, + /* Note: Do not replace "^ SLOPE_ELEVATED" with ComplementSlope(). The slope might be steep. */ + res = DoCommand(tile, Chance16(1, 16) ? cur_slope : cur_slope ^ SLOPE_ELEVATED, 0, DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_TERRAFORM_LAND); } if (CmdFailed(res) && Chance16(1, 3)) { @@ -790,8 +786,8 @@ static void LevelTownLand(TileIndex tile) if (tileh == SLOPE_FLAT) return; /* First try up, then down */ - if (!TerraformTownTile(tile, ~tileh & 0xF, 1)) { - TerraformTownTile(tile, tileh & 0xF, 0); + if (!TerraformTownTile(tile, ~tileh & SLOPE_ELEVATED, 1)) { + TerraformTownTile(tile, tileh & SLOPE_ELEVATED, 0); } } @@ -914,7 +910,7 @@ static bool GrowTownWithRoad(const Town *t, TileIndex tile, RoadBits rcmd) * @param bridge_dir The valid direction in which to grow a bridge * @return true if a bridge has been build else false */ -static bool GrowTownWithBridge(const Town *t, TileIndex tile, DiagDirection bridge_dir) +static bool GrowTownWithBridge(const Town *t, const TileIndex tile, const DiagDirection bridge_dir) { assert(bridge_dir < DIAGDIR_END); @@ -922,33 +918,25 @@ static bool GrowTownWithBridge(const Town *t, TileIndex tile, DiagDirection brid if (slope == SLOPE_FLAT) return false; // no slope, no bridge /* Make sure the direction is compatible with the slope. - * If any of the following bits match, the slope is forbidden for - * that diagdir. This means 5 non-steep slopes, and 3 steep-slopes - * per diagdir. - * 0 -> 0b1100 - * 1 -> 0b0110 - * 2 -> 0b0011 - * 3 -> 0b1001 - * 0xCC is 0b11001100, so we just shift it right with - * the direction to get the forbidden slope mask. */ - if (HASBITS(slope & 0x0F, 0xCC >> bridge_dir)) return false; + * Well we check if the slope has an up bit set in the + * reverse direction. */ + if (HASBITS(slope, InclinedSlope(bridge_dir))) return false; /* Assure that the bridge is connectable to the start side */ if (!(GetTownRoadBits(TileAddByDiagDir(tile, ReverseDiagDir(bridge_dir))) & DiagDirToRoadBits(bridge_dir))) return false; /* We are in the right direction */ - uint8 bridge_length = 0; // This value stores the length of the possible bridge + uint8 bridge_length = 0; // This value stores the length of the possible bridge TileIndex bridge_tile = tile; // Used to store the other waterside - int delta = TileOffsByDiagDir(bridge_dir); - + const int delta = TileOffsByDiagDir(bridge_dir); do { if (bridge_length++ >= 11) { /* Max 11 tile long bridges */ return false; } bridge_tile += delta; - } while (TileX(bridge_tile) != 0 && TileY(bridge_tile) != 0 && IsWaterTile(bridge_tile) && TileX(bridge_tile) != 0); + } while (TileX(bridge_tile) != 0 && TileY(bridge_tile) != 0 && IsWaterTile(bridge_tile)); /* no water tiles in between? */ if (bridge_length == 1) return false; -- cgit v1.2.3-70-g09d2