interface IHeightmapDataset in Tinman.Terrain.Heightmaps

interface	IHeightmapDataset	extends	IDataset
			IHeightmap

Attributes

CanUpdate

Does this map allow updates to its content (i.e. sample data and/or metadata)?

property	CanUpdate { get }
type	bool
value		true if the map content can be updated, false if not.
inherited	IMapEntity.CanUpdate

DataId

Returns a unique identifier for this dataset.

property	DataId { get }
type	DatasetId
value		The unique dataset identifier.
inherited	IDataset.DataId

Georef

Returns georeferencing information.

property	Georef { get }
type	Raster
value		The georeferencing object or null if no georeferencing is available.
inherited	IGeorefInfo.Georef

Height

Number of heightmap samples along the Y-axis.

property	Height { get }
type	int32
value	[>0]	Heightmap height, in samples.
inherited	IHeightmap.Height

Horizontal

Returns the estimated horizontal resolution in terrain-space.

property	Horizontal { get }
type	float64
value	[>0]	The ground sample distance, in Metre.
inherited	IHeightmap.Horizontal

See also:

IGeorefInfo.Georef

Info

Returns dataset metadata information.

property	Info { get }
type	IDatasetInfo
value	[not-null]	The metadata information object.
inherited	IDataset.Info

IsEmpty

Is this an immutable heightmap which only contains default sample data?

property	IsEmpty { get }
type	bool
value		true if all samples of this heightmap are equal to Default, false if not.
inherited	IHeightmap.IsEmpty

IsScaled

Has this heightmap been scaled (either directly or indirectly)?

property	IsScaled { get }
type	bool
value		true if the heightmap contains scaled data, false if not.
inherited	IHeightmap.IsScaled

See also:

IHeightmapOps.Scale

LayerMask

The mask of heightmap layers this object uses.

property	LayerMask { get }
type	HeightmapLayer
value		Bitwise combination of HeightmapLayer values.
inherited	IHeightmapLayers.LayerMask

Remarks:

These heightmap layers store actual terrain data:

• Elevation:
  The terrain elevation, measured upwards from the base geometry (usually an ellipsoid). See VerticalRange.
• Texture:
  A 64-bit ARGB color value that describes the terrain surface (e.g. surface reflectance). See Colors.
• Material:
  A 64-bit ARGB material token that describes the terrain surface (e.g. land cover). See MaterialToken.

Missing data is represented with the Coverage layer. It describes how much information is present in a stored heightmap sample. The semantics of coverage with heightmap samples is the same as premultiplied alpha with texture samples. A LayerMask without Coverage means that all samples are fully solid. If a LayerMask contains the Coverage layer but no others, the coverage values are used to represent 'holes' in the terrain (e.g. creating holes for caves, tunnels, etc.).

LifecycleState

Returns the lifecycle state of this object.

property	LifecycleState { get }
type	LifecycleState
value		The lifecycle state.
inherited	ILifecycleState.LifecycleState

Map

Returns a MapInfo value that describes the used map raster.

property	Map { get }
type	MapInfo
value		The map info value.
inherited	IMapInfo.Map

OnUpdated

Event for listening to updates made to this heightmap.

property	OnUpdated { get }
type	IEventGeneric<HeightmapEventArgs>
value	[not-null]	The event object.
inherited	IHeightmap.OnUpdated

Remarks:

This event will be fired by the thread that performs the map update.

PathInfo

Returns a Path object that represents the file path this object is associated with.

property	PathInfo { get }
type	Path
value	[not-null]	The path info.
inherited	IPathInfo.PathInfo

Remarks:

Objects that do not have a meaningful file path association simply return Unknown.

SampleFormat

The heightmap sample format of this heightmap dataset.

property	SampleFormat { get }
type	IHeightmapFormat
value	[not-null]	The sample format.

Size

Cubemap size of heightmap.

property	Size { get }
type	int32
value	[pow2+1]	Heightmap size, in samples.
inherited	IHeightmap.Size

Type

The heightmap type (rectangular or cubic).

property	Type { get }
type	MapType
value		The heightmap type.
inherited	IHeightmap.Type

Vertical

Returns the terrain-space range of elevation values.

property	Vertical { get }
type	VerticalRange
value		The terrain-space elevation range, in vertical units (see VerticalUnit).
inherited	IHeightmap.Vertical

Remarks:

The default value is Default if Elevation or Displacement is present and None otherwise.

Width

Number of heightmap samples along the X-axis.

property	Width { get }
type	int32
value	[>0]	Heightmap width, in samples.
inherited	IHeightmap.Width

Methods

AcquireTry

Acquires a strong reference to this disposable object.

[OwnerReturn, ThreadSafe]
method	AcquireTry ()
type	IDisposable
returns			this if a new strong reference has been acquired, null if this object is already being disposed.
inherited	IDisposable.AcquireTry

Remarks:

The object will not be actually disposed by calls to Dispose when there is at least one strong reference left. Code that calls the AcquireTry method is responsible for calling the Dispose method accordingly.

This method is not intended to be used in performance-critical code. It should only be used to high-level resource management.

Border

Pads this heightmap to the smallest fitting size of 2^n+1.

[OwnerReturn, OwnerThis]
method	Border (HeightmapSample borderSample, int32 borderFalloff)
type	IHeightmap
params	borderSample		The border heightmap sample.
	borderFalloff	[>0]	Width of the border falloff region, in heightmap samples.
returns		[not-null]	The padded heightmap.
inherited	IHeightmapOps.Border

Remarks:

This method will add a border region at the right and bottom edges of a rectangular heightmap (see Rect). A smooth falloff is computed at the heightmap edges in order to avoid unnecessary triangles being created by CLOD mesh refinement for overly sharp corners.

Clip

Clips away portions of this heightmap, according to the Coverage layer of the given heightmap.

[OwnerReturn, OwnerThis]
method	Clip ([Owner] IHeightmap mask, bool inverse = false)
type	IHeightmap
params	mask	[not-null]	The heightmap that is used as the clip mask (see remarks).
	inverse		Invert the coverage values in mask before clipping? Defaults to false.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.Clip

Remarks:

The coverage values of the returned heightmap are computed like this:

inverse == false : c_out = c_in * c_mask
inverse == true  : c_out = in * (1 - c_mask)

where c_out is the normalized coverage value (i.e. in the range [0..1]) of the returned heightmap, c_in is the normalized coverage value of this heightmap and c_arg is the normalized coverage value of mask.

Combine

Adds detail to this heightmap by combining it with the given heightmap.

[OwnerReturn, OwnerThis]
method	Combine ([Owner] IHeightmap detail, ColorOp textureOp = ColorOp.Blend)
type	IHeightmap
params	detail	[not-null]	The detail heightmap.
	textureOp		The color operation to apply to the Texture layer, if present. Defaults to Blend.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.Combine

Remarks:

The heightmap samples of this heightmap (source) are modified using the samples of the given detail heightmap (detail) according to these rules:

• Coverage:
  The coverage of this heightmap will remain unchanged. The coverage of the given detail heightmap will be ignored.
• Elevation:
  The terrain-space elevation values (see VerticalRange) of this heightmap and the given detail heightmap are added; then the elevation sum is converted back to elevation values using the combined vertical range.
• Texture:
  The given color operation (see textureOp) is applied to the texture color of this heightmap (first) and the color of the given detail heightmap ( second).
• Material:
  The material tokens of this heightmap are mixed with the tokens of the detail heightmap: If the weight sum (WeightSum) of the detail token is greater than or equal to 255, the source token will be replaced with the detail token. Otherwise, the source token will be gradually blend into the detail token (see Mix).
• Displacement:
  The terrain-space displacement values (see VerticalRange) of this heightmap and the given detail heightmap are added; then the displacement sum is converted back to displacement values using the combined vertical range.

Dispose

Releases all resources held by this object if there are no more strong references to it, decrements the reference counter by one otherwise.

[Dispose, OwnerThis, ThreadSafe]
method	Dispose ()
inherited	IDisposable.Dispose

Remarks:

The Dispose method silently returns if the object has already been disposed.

Flush

Flushes all cached data.

method	Flush ()
inherited	IFlushable.Flush

Remarks:

Performing a flush may result in I/O work. Depending on the semantics of the implementing class, this work may need to be wrapped in special Begin / End method calls. See the documentation of the implementing classes for details.

In case this object represents a read-only resource, calling the Flush method has no effect.

GetRegion

Reads a block of samples from the heightmap.

[ThreadSafe]
method	GetRegion (CubemapFaceRect region, HeightmapLayer layers = HeightmapLayer.All, int32 step = 1, HeightmapRegion buffer = null, int32 bufferX = 0, int32 bufferY = 0, bool smooth = false)
type	HeightmapRegion
params	region		The rectangular cubemap face region to fetch.
	layers		The heightmap layers to fetch. Defaults to All.
	step	[pow2]	Step distance between samples in region. Defaults to 1.
	buffer		The output heightmap sample buffer. If null or too small, a new buffer will be created. Defaults to null.
	bufferX	[>=0]	X-coordinate of top-left corner of target rectangle in buffer. Defaults to 0.
	bufferY	[>=0]	Y-coordinate of top-left corner of target rectangle buffer. Defaults to 0.
	smooth		Apply smooth filtering?
returns			The heightmap buffer or null if there are no samples to fetch and buffer is null.
inherited	IHeightmap.GetRegion

Remarks:

The region coordinates will be aligned to the closest multiple of the step distance. See StepAlign for details.

All heightmap samples that lie outside of the valid coordinate range of this heightmap have a Coverage of 0.

Only the heightmap layers (excluding Coverage) present in layers and the LayerMask of this heightmap will be filled in buffer. The Coverage layer will be filled if it is contained in layers, regardless of whether it is defined by LayerMask or not.

This method will not set Horizontal or Vertical in buffer resp. the returned buffer. The calling code is responsible for doing so if necessary.

See also:

IHeightmap.HasRegion

GetSample

Reads a single sample from the heightmap.

[ThreadSafe]
method	GetSample (int32 x, int32 y, int32 z = 0)
type	HeightmapSample
params	x		X-coordinate of sample.
	y		Y-coordinate of sample.
	z		Z-coordinate of sample. Defaults to 0 (i.e. NegZ).
inherited	IHeightmap.GetSample

Remarks:

The returned heightmap sample will store values for each layer in LayerMask, all other values will have their respective default value. If the heightmap sample lies outside of the valid coordinate range of this heightmap, it will have a Coverage of 0, even if LayerMask does not contain the Coverage layer.

GetSamples

Reads multiple samples from the heightmap in a bulk operation.

[ThreadSafe]
method	GetSamples (Vec3I[] xyz, int32 count, HeightmapSamples buffer, HeightmapLayer layers = HeightmapLayer.All)
params	xyz	[not-null]	Array of cubemap coordinates of heightmap map samples to fetch. The coordinates must be specified for a heightmap of size MaxSize. Each heightmap implementation will translate these normalized coordinates into its own size using bit shifting. This way the coordinates array can be shared by heightmaps of different sizes.
	count	[>=0]	Total number of heightmap samples to fetch.
	buffer	[not-null]	The heightmap sample buffer to use. If null or too small, a new buffer will be created.
	layers		The heightmap layers to fetch. Defaults to All.
inherited	IHeightmap.GetSamples

Remarks:

All heightmap samples that lie outside of the valid coordinate range of this heightmap will have a Coverage or 0.

Only the heightmap layers (excluding Coverage) present in layers and the LayerMask of this heightmap will be filled in buffer. The Coverage layer will be filled if it is contained in layers, regardless of whether it is defined by LayerMask or not.

HasRegion

Determines if this heightmap contains data in the given region.

[ThreadSafe]
method	HasRegion (CubemapFaceRect region, CoverageFlags flags = CoverageFlags.Some)
type	CoverageFlags
params	region		The region to check for data.
	flags		The coverage flags that need to be determined. Using specific flags here will allow implementations to early-exit. Defaults to Some (i.e. all flags).
returns			The resulting flag bits (contains at least those bits defined by flags ).
inherited	IHeightmap.HasRegion

Remarks:

The following semantic relaxations can be exploited by implementing methods in order to improve performance:

• Contiguous blocks containing more than one sample must be reported. Others may be reported but can be as well be ignored.
• Samples with partial coverage may be treated as non-existent samples.
• Samples may be grouped in blocks up to 512x512 in size.

Merge

Merges the given heightmap with this one. The coverage of both heightmaps will be taken into account during merging.

[OwnerReturn, OwnerThis]
method	Merge ([Owner] IHeightmap second)
type	IHeightmap
params	second	[not-null]	The second heightmap.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.Merge

Remarks:

Merged heightmaps fill data into heightmap samples in order, with heightmaps at a later stage overwriting sample data written by heightmaps of an earlier stage.

Both heightmaps (this one and second) will be scaled to the maximum possible size.

Scale

Returns a scaled version of this heightmap.

[OwnerReturn, OwnerThis]
method	Scale (int32 newSize)
type	IHeightmap
params	newSize	[pow2+1]	The scaled internal size (see Type). The minimum internal size is MinSize.
returns		[not-null]	The scaled heightmap.
inherited	IHeightmapOps.Scale

Remarks:

The maximum upscaling factor for heightmaps is 65536, so the given condition should be met when upscaling a heightmap (otherwise only the 16 most significant bits of the interpolation factor will be used):

(newSize - 1) / (Size - 1) <= 65536

where newSize is the new heightmap size and Type is the current size of this heightmap.

Split

Splits the layers of this heightmap.

[OwnerReturn, OwnerThis]
method	Split (HeightmapLayer layers)
type	IHeightmap
params	layers		The heightmap layers to retain in the split heightmap.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.Split

ToConfig

Returns the configuration value that describes this object.

method	ToConfig ()
type	ConfigValue
returns		[not-null]	The configuration value.
inherited	IConfigurable.ToConfig

Remarks:

All configurable objects need to implement this interface. For simple types, it is preferable to delegate to ToValue.

The returned value may be of type Invalid, which means that this object in its current state cannot be described with the configuration API.

Before returning the resulting configuration value, Cache must be called on it, passing this IConfigurable object as parameter.

ToPyramid

Wraps this heightmap in a pixel pyramid.

[OwnerReturn, OwnerThis]
method	ToPyramid (int32 tileSize = 256, int32 tilePad = 0, int32 levels = 0, IPixelLayer pixelLayer = null, PyramidFlags flags = PyramidFlags.None)
type	IPixelPyramid
params	tileSize	[pow2]	The tile size. Defaults to 256.
	tilePad	[>=0]	The tile padding. Defaults to 0.
	levels	[>=0]	Defines how many pyramid levels (starting at the bottommost level) shall contain data. The heightmap sample step is 1 for the bottommost level and is multiplied by two for each parent level. If 0, all pyramid levels will contain data. Defaults to 0.
	pixelLayer		Optional pixel layer to use. Defaults to null.
	flags		Optional pyramid flags. Defaults to None.
returns		[not-null]	The pixel pyramid.
inherited	IHeightmapOps.ToPyramid

TransformRange

Translates the normalized elevation values of this heightmap to the given range.

[OwnerReturn, OwnerThis]
method	TransformRange (VerticalRange range, UnitOfMeasure unit = null, bool reinterpret = false)
type	IHeightmap
params	range		The range to translate to (see Vertical).
	unit		The vertical unit of range. If null, Metre will be used. Defaults to null.
	reinterpret		Keep elevation values of this heightmap and reinterpret them according to range and unit, instead of scaling them? Defaults to false.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.TransformRange

UpdateFormat

Updates the binary format of this heightmap by adding new heightmap layers.

[ThreadSafe]
method	UpdateFormat (IHeightmapFormat format)
params	format	[not-null]	The heightmap format used for adding new heightmap layers.

Remarks:

The given format is split into single components (via Collect), so that each component represents a single heightmap layer. Then, all those components are dropped which layer is already contained in this heightmap. The remaining components are then appended to the heightmap format.

See also:

IMapEntity.CanUpdate

UpdateGeoref

Updates georeferencing data of this heightmap.

[ThreadSafe]
method	UpdateGeoref (Raster georef)
params	georef		The new georeferencing data or null.
inherited	IMapEntity.UpdateGeoref

See also:

IMapEntity.CanUpdate

UpdateInfo

Updates metadata information of this heightmap.

[ThreadSafe]
method	UpdateInfo (IDatasetInfo info)
params	info	[not-null]	The new metadata information.
inherited	IDataset.UpdateInfo

See also:

IMapEntity.CanUpdate

UpdateRange

Updates the vertical range of this heightmap.

[ThreadSafe]
method	UpdateRange (VerticalRange range)
params	range		The new vertical range.
inherited	IHeightmap.UpdateRange

See also:

IMapEntity.CanUpdate

UpdateRegion

Updates a region of this heightmap in an atomic operation.

[ThreadSafe]
method	UpdateRegion (CubemapFaceRect region, HeightmapRegion buffer, HeightmapRegionDelegate combine = null, HeightmapLayer layers = HeightmapLayer.All, int32 bufferX = 0, int32 bufferY = 0, object userData = null)
params	region		The cubemap face region to update.
	buffer	[not-null]	The heightmap sample buffer to use (see remarks).
	combine		Optional delegate for combining source and target heightmap samples. Defaults to null.
	layers		The heightmap layers to update.
	bufferX	[>=0]	X-coordinate of top-left sample in buffer to use. Defaults to 0.
	bufferY	[>=0]	Y-coordinate of top-left sample in buffer to use. Defaults to 0.
	userData		Optional user data object to pass to combine. Defaults to null.
inherited	IHeightmap.UpdateRegion

Remarks:

Depending on the values passed to buffer and combine, the following operation is performed by this method:

• combine is null:
  The given heightmap buffer are copied to this heightmap, overwriting any existing data. The Vertical property of the given buffer is ignored, i.e. elevation samples (if present) will not be transformed, only copied.
• combine is not null:
  The given heightmap buffer is filled with existing data from this heightmap. Then, the combine delegate is invoked (which modifies the heightmap samples in-place) and the resulting buffer is written back to this heightmap. The Horizontal and Vertical properties of buffer are set before the combine method is called (using the values of this heightmap).

See also:

IMapEntity.CanUpdate

UseCache

Tells this dataset instance to make use of the given dataset file cache.

method	UseCache (DatasetFileCache cache)
params	cache		The dataset file cache or null to disable file caching.
inherited	IDataset.UseCache

Remarks:

File-based dataset caching is usually performed when streaming datasets over the internet.

UseColorRamp

Return a heightmap that computes texture colors using an elevation-based color ramp.

[OwnerReturn, OwnerThis]
method	UseColorRamp (IColorRamp colorRamp)
type	IHeightmap
params	colorRamp	[not-null]	The color ramp to use.
returns		[not-null]	The resulting heightmap.
inherited	IHeightmapOps.UseColorRamp

Remarks:

The terrain-space values of the Elevation layer (according to the vertical range and unit of the heightmap) are fed into the color ramp. The resulting diffuse color is used as the Texture layer.