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slope_func.h File Reference

Functions related to slopes. More...

`#include "core/math_func.hpp"`
`#include "slope_type.h"`
`#include "direction_type.h"`
`#include "tile_type.h"`

Go to the source code of this file.

## Functions
static bool | IsValidCorner (Corner corner)
| Rangecheck for Corner enumeration.
static bool | IsSteepSlope (Slope s)
| Checks if a slope is steep.
static bool | IsHalftileSlope (Slope s)
| Checks for non-continuous slope on halftile foundations.
static Slope | RemoveHalftileSlope (Slope s)
| Removes a halftile slope from a slope.
static Slope | ComplementSlope (Slope s)
| Return the complement of a slope.
static bool | IsSlopeWithOneCornerRaised (Slope s)
| Tests if a specific slope has exactly one corner raised.
static Slope | SlopeWithOneCornerRaised (Corner corner)
| Returns the slope with a specific corner raised.
static bool | HasSlopeHighestCorner (Slope s)
| Tests if a slope has a highest corner (i.e.
static Corner | GetHighestSlopeCorner (Slope s)
| Returns the highest corner of a slope (one corner raised or a steep slope).
static Corner | GetHalftileSlopeCorner (Slope s)
| Returns the leveled halftile of a halftile slope.
static int | GetSlopeMaxZ (Slope s)
| Returns the height of the highest corner of a slope relative to TileZ (= minimal height)
static int | GetSlopeMaxPixelZ (Slope s)
| Returns the height of the highest corner of a slope relative to TileZ (= minimal height)
static Corner | OppositeCorner (Corner corner)
| Returns the opposite corner.
static bool | IsSlopeWithThreeCornersRaised (Slope s)
| Tests if a specific slope has exactly three corners raised.
static Slope | SlopeWithThreeCornersRaised (Corner corner)
| Returns the slope with all except one corner raised.
static Slope | SteepSlope (Corner corner)
| Returns a specific steep slope.
static bool | IsInclinedSlope (Slope s)
| Tests if a specific slope is an inclined slope.
static DiagDirection | GetInclinedSlopeDirection (Slope s)
| Returns the direction of an inclined slope.
static Slope | InclinedSlope (DiagDirection dir)
| Returns the slope that is inclined in a specific direction.
static Slope | HalftileSlope (Slope s, Corner corner)
| Adds a halftile slope to a slope.
static bool | IsFoundation (Foundation f)
| Tests for FOUNDATION_NONE.
static bool | IsLeveledFoundation (Foundation f)
| Tests if the foundation is a leveled foundation.
static bool | IsInclinedFoundation (Foundation f)
| Tests if the foundation is an inclined foundation.
static bool | IsNonContinuousFoundation (Foundation f)
| Tests if a foundation is a non-continuous foundation, i.e.
static Corner | GetHalftileFoundationCorner (Foundation f)
| Returns the halftile corner of a halftile-foundation.
static bool | IsSpecialRailFoundation (Foundation f)
| Tests if a foundation is a special rail foundation for single horizontal/vertical track.
static Corner | GetRailFoundationCorner (Foundation f)
| Returns the track corner of a special rail foundation.
static Foundation | FlatteningFoundation (Slope s)
| Returns the foundation needed to flatten a slope.
static Foundation | InclinedFoundation (Axis axis)
| Returns the along a specific axis inclined foundation.
static Foundation | HalftileFoundation (Corner corner)
| Returns the halftile foundation for single horizontal/vertical track.
static Foundation | SpecialRailFoundation (Corner corner)
| Returns the special rail foundation for single horizontal/vertical track.
static uint | SlopeToSpriteOffset (Slope s)
| Returns the Sprite offset for a given Slope.

## Detailed Description

Functions related to slopes.

Definition in file slope_func.h.

## Function Documentation

static Slope ComplementSlope | ( | Slope | s | ) |
| inline static

Return the complement of a slope.

This method returns the complement of a slope. The complement of a slope is a slope with raised corner which aren't raised in the given slope.

Precondition
  The slope must neither be steep nor a halftile slope.

Parameters

  s | The Slope to get the complement.

Returns
  a complement Slope of the given slope.

Definition at line 78 of file slope_func.h.

References IsHalftileSlope(), IsSteepSlope(), and SLOPE_ELEVATED.

Referenced by CmdBuildTunnel(), DrawTrackBits(), IsRoadAllowedHere(), IsSlopeWithThreeCornersRaised(), and SlopeWithThreeCornersRaised().

static Foundation FlatteningFoundation | ( | Slope | s | ) |
| inline static

Returns the foundation needed to flatten a slope.

The returned foundation is either FOUNDATION_NONE if the tile was already flat, or FOUNDATION_LEVELED.

Parameters

  s | The current Slope.

Returns
  The needed Foundation.

Definition at line 371 of file slope_func.h.

References FOUNDATION_LEVELED, FOUNDATION_NONE, and SLOPE_FLAT.

Referenced by GetBridgeFoundation(), and GetFoundation_Town().

static Corner GetHalftileFoundationCorner | ( | Foundation | f | ) |
| inline static

Returns the halftile corner of a halftile-foundation.

Precondition
  f != FOUNDATION_STEEP_BOTH

Parameters

  f | The Foundation.

Returns
  The Corner with track.

Definition at line 335 of file slope_func.h.

References FOUNDATION_HALFTILE_N, FOUNDATION_HALFTILE_W, and IsInsideMM().

Referenced by ApplyFoundationToSlope(), DrawFoundation(), and DrawTrackBits().

static Corner GetHalftileSlopeCorner | ( | Slope | s | ) |
| inline static

Returns the leveled halftile of a halftile slope.

Precondition
  The slope must be a halftile slope.

Parameters

  s | The Slope.

Returns
  The corner of the leveled halftile.

Definition at line 150 of file slope_func.h.

References IsHalftileSlope().

Referenced by DrawAutorailSelection(), DrawCatenaryRailway(), DrawTileSelection(), DrawTileSelectionRect(), GetPartialPixelZ(), and GetSlopePixelZOnEdge().

static Corner GetHighestSlopeCorner | ( | Slope | s | ) |
| inline static

Returns the highest corner of a slope (one corner raised or a steep slope).

Precondition
  The slope must be a slope with one corner raised or a steep slope. A halftile slope is ignored.

Parameters

  s | The Slope.

Returns
  Highest corner.

Definition at line 128 of file slope_func.h.

References RemoveHalftileSlope(), SLOPE_E, SLOPE_N, SLOPE_S, SLOPE_STEEP_E, SLOPE_STEEP_N, SLOPE_STEEP_S, SLOPE_STEEP_W, and SLOPE_W.

Referenced by ApplyFoundationToSlope(), CheckRoadSlope(), DrawFoundation(), DrawTrackBits(), FloodHalftile(), GetRailFoundation(), GetRoadFoundation(), and RemoveRoad().

static DiagDirection GetInclinedSlopeDirection | ( | Slope | s | ) |
| inline static

Returns the direction of an inclined slope.

Parameters

  s | A Slope

Returns
  The direction the slope goes up in. Or INVALID_DIAGDIR if the slope is not an inclined slope.

Definition at line 241 of file slope_func.h.

References DIAGDIR_NE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_SW, INVALID_DIAGDIR, SLOPE_NE, SLOPE_NW, SLOPE_SE, and SLOPE_SW.

Referenced by CmdBuildDock(), CmdBuildLock(), CmdBuildTunnel(), GetOtherAqueductEnd(), BuildDocksToolbarWindow::OnPlaceObject(), and BuildDocksToolbarWindow::OnPlacePresize().

static Corner GetRailFoundationCorner | ( | Foundation | f | ) |
| inline static

Returns the track corner of a special rail foundation.

Parameters

  f | The Foundation.

Returns
  The Corner with track.

Definition at line 358 of file slope_func.h.

References FOUNDATION_RAIL_W, and IsSpecialRailFoundation().

Referenced by ApplyFoundationToSlope(), and DrawFoundation().

static int GetSlopeMaxPixelZ | ( | Slope | s | ) |
| inline static

Returns the height of the highest corner of a slope relative to TileZ (= minimal height)

Parameters

  s | The Slope.

Returns
  Relative height of highest corner.

Definition at line 175 of file slope_func.h.

References GetSlopeMaxZ(), and TILE_HEIGHT.

Referenced by GetPartialPixelZ().

static int GetSlopeMaxZ | ( | Slope | s | ) |
| inline static

Returns the height of the highest corner of a slope relative to TileZ (= minimal height)

Parameters

  s | The Slope.

Returns
  Relative height of highest corner.

Definition at line 162 of file slope_func.h.

References IsSteepSlope(), and SLOPE_FLAT.

Referenced by AutoslopeCheckForEntranceEdge(), CheckBuildableTile(), and GetSlopeMaxPixelZ().

static Foundation HalftileFoundation | ( | Corner | corner | ) |
| inline static

Returns the halftile foundation for single horizontal/vertical track.

Parameters

  corner | The Corner with the track.

Returns
  The wanted Foundation.

Definition at line 393 of file slope_func.h.

References FOUNDATION_HALFTILE_W, and IsValidCorner().

Referenced by DrawTrackBits(), and GetRailFoundation().

static Slope HalftileSlope | ( | Slope | s,
|  | Corner | corner
| ) |  |
| inline static

Adds a halftile slope to a slope.

Parameters

  s | Slope without a halftile slope.
  corner | The Corner of the halftile.

Returns
  The Slope s with the halftile slope added.

Definition at line 276 of file slope_func.h.

References IsValidCorner(), and SLOPE_HALFTILE.

Referenced by ApplyFoundationToSlope().

static bool HasSlopeHighestCorner | ( | Slope | s | ) |
| inline static

Tests if a slope has a highest corner (i.e.

one corner raised or a steep slope).

Note: A halftile slope is ignored.

Parameters

  s | The Slope.

Returns
  true iff the slope has a highest corner.

Definition at line 115 of file slope_func.h.

References IsSlopeWithOneCornerRaised(), IsSteepSlope(), and RemoveHalftileSlope().

Referenced by GetBridgeFoundation().

static Foundation InclinedFoundation | ( | Axis | axis | ) |
| inline static

Returns the along a specific axis inclined foundation.

Parameters

  axis | The Axis.

Returns
  The needed Foundation.

Definition at line 382 of file slope_func.h.

References AXIS_X, FOUNDATION_INCLINED_X, and FOUNDATION_INCLINED_Y.

Referenced by GetBridgeFoundation().

static Slope InclinedSlope | ( | DiagDirection | dir | ) |
| inline static

Returns the slope that is inclined in a specific direction.

Parameters

  dir | A DiagDirection

Returns
  The Slope that goes up in direction dir.

Definition at line 258 of file slope_func.h.

References DIAGDIR_NE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_SW, SLOPE_NE, SLOPE_NW, SLOPE_SE, and SLOPE_SW.

Referenced by AdjustTileh(), CanBuildDepotByTileh(), and GrowTownWithBridge().

static bool IsFoundation | ( | Foundation | f | ) |
| inline static

Tests for FOUNDATION_NONE.

Parameters

  f | Maybe a Foundation.

Returns
  true iff f is a foundation.

Definition at line 289 of file slope_func.h.

References FOUNDATION_NONE.

Referenced by ApplyFoundationToSlope(), and DrawFoundation().

static bool IsHalftileSlope | ( | Slope | s | ) |
| inline static

Checks for non-continuous slope on halftile foundations.

Parameters

  s | The given Slope.

Returns
  True if the slope is non-continuous, else false.

Definition at line 49 of file slope_func.h.

References SLOPE_HALFTILE.

Referenced by ComplementSlope(), DrawAutorailSelection(), DrawCatenaryRailway(), DrawTileSelection(), DrawTileSelectionRect(), GetHalftileSlopeCorner(), GetPartialPixelZ(), GetSlopePixelZOnEdge(), GetSlopeZInCorner(), and IsSlopeWithThreeCornersRaised().

static bool IsInclinedFoundation | ( | Foundation | f | ) |
| inline static

Tests if the foundation is an inclined foundation.

Parameters

  f | The Foundation.

Returns
  true iff f is an inclined foundation.

Definition at line 311 of file slope_func.h.

References FOUNDATION_INCLINED_X, and FOUNDATION_INCLINED_Y.

Referenced by DrawFoundation().

static bool IsInclinedSlope | ( | Slope | s | ) |
| inline static

Tests if a specific slope is an inclined slope.

Parameters

  s | The Slope

Returns
  true iff the slope is inclined.

Definition at line 230 of file slope_func.h.

References SLOPE_NE, SLOPE_NW, SLOPE_SE, and SLOPE_SW.

Referenced by CmdBuildCanal(), and FlowsDown().

static bool IsLeveledFoundation | ( | Foundation | f | ) |
| inline static

Tests if the foundation is a leveled foundation.

Parameters

  f | The Foundation.

Returns
  true iff f is a leveled foundation.

Definition at line 300 of file slope_func.h.

References FOUNDATION_LEVELED.

Referenced by ApplyFoundationToSlope(), and DrawFoundation().

static bool IsNonContinuousFoundation | ( | Foundation | f | ) |
| inline static

Tests if a foundation is a non-continuous foundation, i.e.

halftile-foundation or FOUNDATION_STEEP_BOTH.

Parameters

  f | The Foundation.

Returns
  true iff f is a non-continuous foundation

Definition at line 322 of file slope_func.h.

References FOUNDATION_HALFTILE_N, FOUNDATION_STEEP_BOTH, and IsInsideMM().

Referenced by ApplyFoundationToSlope(), DrawFoundation(), DrawTrackBits(), and FloodHalftile().

static bool IsSlopeWithOneCornerRaised | ( | Slope | s | ) |
| inline static

Tests if a specific slope has exactly one corner raised.

Parameters

  s | The Slope

Returns
  true iff exactly one corner is raised

Definition at line 90 of file slope_func.h.

References SLOPE_E, SLOPE_N, SLOPE_S, and SLOPE_W.

Referenced by CanPlantTreesOnTile(), CheckRoadSlope(), CmdBuildSingleRail(), CmdPlantTree(), CmdRemoveSingleRail(), DoFloodTile(), FloodHalftile(), GetFloodingBehaviour(), GetRailFoundation(), GetRoadFoundation(), HasSlopeHighestCorner(), IsSlopeWithThreeCornersRaised(), and TestAutoslopeOnRailTile().

static bool IsSlopeWithThreeCornersRaised | ( | Slope | s | ) |
| inline static

Tests if a specific slope has exactly three corners raised.

Parameters

  s | The Slope

Returns
  true iff exactly three corners are raised

Definition at line 197 of file slope_func.h.

References ComplementSlope(), IsHalftileSlope(), IsSlopeWithOneCornerRaised(), and IsSteepSlope().

Referenced by FloodHalftile(), and GetRailFoundation().

static bool IsSpecialRailFoundation | ( | Foundation | f | ) |
| inline static

Tests if a foundation is a special rail foundation for single horizontal/vertical track.

Parameters

  f | The Foundation.

Returns
  true iff f is a special rail foundation for single horizontal/vertical track.

Definition at line 347 of file slope_func.h.

References FOUNDATION_RAIL_N, FOUNDATION_RAIL_W, and IsInsideMM().

Referenced by ApplyFoundationToSlope(), DrawFoundation(), and GetRailFoundationCorner().

static bool IsSteepSlope | ( | Slope | s | ) |
| inline static

Checks if a slope is steep.

Parameters

  s | The given Slope.

Returns
  True if the slope is steep, else false.

Definition at line 38 of file slope_func.h.

References SLOPE_STEEP.

Referenced by ApplyFoundationToSlope(), CanBuildDepotByTileh(), CanBuildHouseHere(), CheckBuildableTile(), CheckRailSlope(), CheckRoadSlope(), CmdBuildRoad(), ComplementSlope(), DrawCatenaryRailway(), DrawFoundation(), DrawTileSelection(), DrawTileSelectionRect(), DrawTrackBits(), FloodHalftile(), GetRailFoundation(), GetRoadFoundation(), GetSlopeMaxZ(), HasSlopeHighestCorner(), IsSlopeWithThreeCornersRaised(), IsValidTileForWaypoint(), RemoveRoad(), and SearchTileForStatue().

static bool IsValidCorner | ( | Corner | corner | ) |
| inline static

Rangecheck for Corner enumeration.

Parameters

  corner | A Corner.

Returns
  true iff corner is in a valid range.

Definition at line 26 of file slope_func.h.

References IsInsideMM().

Referenced by CornerToTrackBits(), DrawTrackBits(), HalftileFoundation(), HalftileSlope(), SlopeWithOneCornerRaised(), and SpecialRailFoundation().

static Corner OppositeCorner | ( | Corner | corner | ) |
| inline static

Returns the opposite corner.

Parameters

  corner | A Corner.

Returns
  The opposite corner to "corner".

Definition at line 186 of file slope_func.h.

Referenced by ApplyFoundationToSlope(), DrawAutorailSelection(), DrawTileSelectionRect(), DrawTrackBits(), FloodHalftile(), GetRailFoundation(), and SteepSlope().

static Slope RemoveHalftileSlope | ( | Slope | s | ) |
| inline static

Removes a halftile slope from a slope.

Non-halftile slopes remain unmodified.

Parameters

  s | A Slope.

Returns
  The slope s without its halftile slope.

Definition at line 62 of file slope_func.h.

References SLOPE_HALFTILE_MASK.

Referenced by DrawAutorailSelection(), DrawTileSelection(), DrawTrackFence_NS_1(), DrawTrackFence_NS_2(), DrawTrackFence_WE_1(), DrawTrackFence_WE_2(), GetHighestSlopeCorner(), GetPartialPixelZ(), GetSlopePixelZOnEdge(), HasSlopeHighestCorner(), IsUphillTrackdir(), and TestAutoslopeOnRailTile().

static uint SlopeToSpriteOffset | ( | Slope | s | ) |
| inline static

Returns the Sprite offset for a given Slope.

Parameters

  s | The Slope to get the offset for.

Returns
  The sprite offset for this Slope.

Definition at line 417 of file slope_func.h.

References _slope_to_sprite_offset.

Referenced by DrawTile_TunnelBridge(), DrawTileSelectionRect(), and DrawTrackBits().

static Slope SlopeWithOneCornerRaised | ( | Corner | corner | ) |
| inline static

Returns the slope with a specific corner raised.

Parameters

  corner | The Corner.

Returns
  The Slope with corner "corner" raised.

Definition at line 101 of file slope_func.h.

References IsValidCorner().

Referenced by ApplyFoundationToSlope(), CheckRoadSlope(), DrawFoundation(), DrawTileSelectionRect(), GetRailFoundation(), GetRoadFoundation(), GetSlopePixelZOnEdge(), GetSlopeZInCorner(), RemoveRoad(), and SlopeWithThreeCornersRaised().

static Slope SlopeWithThreeCornersRaised | ( | Corner | corner | ) |
| inline static

Returns the slope with all except one corner raised.

Parameters

  corner | The Corner.

Returns
  The Slope with all corners but "corner" raised.

Definition at line 208 of file slope_func.h.

References ComplementSlope(), and SlopeWithOneCornerRaised().

Referenced by ApplyFoundationToSlope(), DrawAutorailSelection(), DrawFoundation(), DrawTrackBits(), GetRailFoundation(), and SteepSlope().

static Foundation SpecialRailFoundation | ( | Corner | corner | ) |
| inline static

Returns the special rail foundation for single horizontal/vertical track.

Parameters

  corner | The Corner with the track.

Returns
  The wanted Foundation.

Definition at line 405 of file slope_func.h.

References FOUNDATION_RAIL_W, and IsValidCorner().

Referenced by GetRailFoundation().

static Slope SteepSlope | ( | Corner | corner | ) |
| inline static

Returns a specific steep slope.

Parameters

  corner | A Corner.

Returns
  The steep Slope with "corner" as highest corner.

Definition at line 219 of file slope_func.h.

References OppositeCorner(), SLOPE_STEEP, and SlopeWithThreeCornersRaised().

Referenced by GetSlopeZInCorner().