RenderableInterpolatedPoints

Inherits Renderable

RenderableInterpolatedPoints is a version of the RenderablePointCloud class, where the dataset may contain multiple time steps that can be interpolated between. It supports interpolation of both of positions and data values used for color mapping or size.

The dataset should be structured in a way so that the first N rows correspond to the first set of positions for the objects, the next N rows to the second set of positions, and so on. The number of objects in the dataset must be specified in the asset.

MultiTexture: Note that if using multiple textures for the points based on values in the dataset, the used texture will be decided based on the first N set of points.

Members

Name	Documentation	Type	Description	Optional
NumberOfObjects	The number of objects to read from the dataset. Every N:th datapoint will be interpreted as the same point, but at a different step in the interpolation	Integer	Greater or equal to: 1	No
Coloring	Settings related to the coloring of the points, such as a fixed color, color map, etc.	Table	Table parameters	Yes
DataMapping	A dictionary specifying details on how to load the dataset. Updating the data mapping will lead to a new cached version of the dataset	Table	DataMapping	Yes
DrawElements	Enables/Disables the drawing of the points	Boolean	Value of type ‘Boolean’	Yes
Fading	Settings related to fading based on camera distance. Can be used to either fade away or fade in the points when reaching a certain distance from the origin of the dataset	Table	Table parameters	Yes
File	The path to the data file that contains information about the point to be rendered. Can be either a CSV or SPECK file	File	Value of type ‘File’	Yes
Interpolation	Initial settings for the interpolation	Table	Table parameters	Yes
Labels	The labels for the points. If no label file is provided, the labels will be created to match the points in the data file. For a CSV file, you should then specify which column is the ‘Name’ column in the data mapping. For SPECK files the labels are created from the comment at the end of each line	Table	LabelsComponent	Yes
RenderOption	Option wether the point billboards should face the camera or not. Used for non-linear display environments such as fisheye.	String	In list { Camera View Direction, Camera Position Normal }	Yes
SizeSettings	Settings related to the scale of the points, whether they should limit to a certain max size, etc.	Table	Table parameters	Yes
SkipFirstDataPoint	If true, skip the first data point in the loaded dataset	Boolean	Value of type ‘Boolean’	Yes
Texture	Settings related to the texturing of the points	Table	Table parameters	Yes
TransformationMatrix	Transformation matrix to be applied to the position of each object	Matrix4x4<double>	Value of type ‘Matrix4x4’	Yes
Unit	The unit used for all distances. Should match the unit of any distances/positions in the data files	String	In list { m, Km, pc, Kpc, Mpc, Gpc, Gly }	Yes
UseAdditiveBlending	If true (default), the color of points rendered on top of each other is blended additively, resulting in a brighter color where points overlap. If false, no such blending will take place and the color of the point will not be modified by blending. Note that this may lead to weird behaviors when the points are rendered with transparency.	Boolean	Value of type ‘Boolean’	Yes
UseCaching	If true (default), the loaded dataset will be cached so that it can be loaded faster at a later time. This does however mean that any updates to the values in the dataset will not lead to changes in the rendering without first removing the cached file. Set it to false to disable caching. This can be useful for example when working on importing a new dataset	Boolean	Value of type ‘Boolean’	Yes

Inherited members from Renderable

Name	Documentation	Type	Description	Optional
DimInAtmosphere	Enables/Disables if the object should be dimmed when the camera is in the sunny part of an atmosphere	Boolean	Value of type ‘Boolean’	Yes
Enabled	This setting determines whether this object will be visible or not	Boolean	Value of type ‘Boolean’	Yes
Opacity	This value determines the opacity of this renderable. A value of 0 means completely transparent	Double	In range: ( 0,1 )	Yes
RenderBinMode	This value specifies if the renderable should be rendered in the Background,Opaque, Pre/PostDeferredTransparency, or Overlay rendering step	String	In list { Background, Opaque, PreDeferredTransparent, PostDeferredTransparent, Overlay }	Yes
Tag	A single tag or a list of tags that this renderable will respond to when setting properties	Table, or String	Value of type ‘Table’, or Value of type ‘String’	Yes
Type	This tells the type of the renderable	String	Value of type ‘String’	Yes

Table parameters for Coloring

Settings related to the coloring of the points, such as a fixed color, color map, etc.

• Optional: Yes

Name	Documentation	Type	Description	Optional
ColorMapping	Settings related to the choice of color map, parameters, etc.	Table	ColorMappingComponent	Yes
EnableOutline	This setting determines if each point should have an outline or not. An outline is only applied when rendering as colored points (not when using textures).	Boolean	Value of type ‘Boolean’	Yes
FixedColor	This value is used to define the color of the points when no color map isused	Color3	Value of type ‘Color3’	Yes
OutlineColor	This value defines the color of the outline. Darker colors will be less visible if Additive Blending is enabled.	Vector3<double>	Value of type ‘Vector3’	Yes
OutlineWeight	This value defines the color of the outline. Darker colors will be less visible if Additive Blending is enabled.	Double	Value of type ‘Double’	Yes

Table parameters for Fading

Settings related to fading based on camera distance. Can be used to either fade away or fade in the points when reaching a certain distance from the origin of the dataset

• Optional: Yes

Name	Documentation	Type	Description	Optional
Enabled	Enables/disables the Fade-in effect based on camera distance. Automatically set to true if FadeInDistances are specified in the asset.	Boolean	Value of type ‘Boolean’	Yes
FadeInDistances	These values determine the initial and final distances from the origin of the dataset at which the points will start and end fading-in. The distances are specified in the same unit as the points, that is, the one provodied as the Unit, or meters. With normal fading the points are fully visible once the camera is outside this range and fully invisible when inside the range. With inverted fading the situation is the opposite: the points are visible inside hen closer than the min value of the range and invisible when further away.	Vector2<double>	Value of type ‘Vector2’	Yes
Invert	This property can be used the invert the fading so that the points are invisible when the camera is further away than the max fade distance and fully visible when it is closer than the min distance.	Boolean	Value of type ‘Boolean’	Yes

Table parameters for Interpolation

Initial settings for the interpolation

• Optional: Yes

Name	Documentation	Type	Description	Optional
Speed	Affects how long the interpolation takes when triggered using one of the trigger properties. A value of 1 means that a step takes 1 second.	Double	Value of type ‘Double’	Yes
UseSplineInterpolation	If true, the points will be interpolated using a Catmull-Rom spline instead of linearly. This leads to a smoother transition at the breakpoints, i.e. between each step.	Boolean	Value of type ‘Boolean’	Yes
Value	The value to use for interpolation. The max value is set from the number of steps in the dataset, so a step of one corresponds to one step in the dataset and values in-between will be determined using interpolation.	Double	Value of type ‘Double’	Yes

Table parameters for SizeSettings

Settings related to the scale of the points, whether they should limit to a certain max size, etc.

• Optional: Yes

Name	Documentation	Type	Description	Optional
EnableMaxSizeControl	If true, the Max Size property will be used as an upper limit for the size of the point. This reduces the size of the points when approaching them, so that they stick to a maximum visual size depending on the Max Size value.	Boolean	Value of type ‘Boolean’	Yes
MaxSize	This value controls the maximum allowed size for the points, when the max size control feature is enabled. This limits the visual size of the points based on the distance to the camera. The larger the value, the larger the points are allowed to become. In the background, the computations are made by limiting the size to a certain angle based on the field of view of the camera. So a value of 1 limits the point size to take up a maximum of one degree of the view space.	Double	Value of type ‘Double’	Yes
ScaleExponent	This value is used as in exponential scaling to set the absolute size of the point. In general, the larger distance the dataset covers, the larger this value should be. If not included, it is computed based on the maximum positional component of the data points. This is useful for showing the dataset at all, but you will likely want to change it to something that looks good.	Double	Value of type ‘Double’	Yes
ScaleFactor	This value is used as a multiplicative factor to adjust the size of the points, after the exponential scaling and any max size control effects. Simply just increases or decreases the visual size of the points.	Double	Value of type ‘Double’	Yes
SizeMapping	Settings related to scaling the points based on data	Table	SizeMappingComponent	Yes

Table parameters for Texture

Settings related to the texturing of the points

• Optional: Yes

Name	Documentation	Type	Description	Optional
AllowCompression	If true, the textures will be compressed to preserve graphics card memory. This is enabled per default, but may lead to visible artefacts for certain images, especially up close. Set this to false to disable any hardware compression of the textures, and represent each color channel with 8 bits.	Boolean	Value of type ‘Boolean’	Yes
Enabled	If true, use a provided sprite texture to render the point. If false, draw the points using the default point shape.	Boolean	Value of type ‘Boolean’	Yes
File	The path to the texture that should be used as the point sprite. Note that if multiple textures option is set in the asset, by providing a texture folder, this value will be ignored.	File	Value of type ‘File’	Yes
Folder	The folder where the textures are located when using multiple different textures to render the points. Setting this value means that multiple textures shall be used and any single sprite texture file is ignored. Note that the textures can be any format, but rendering efficiency will be best if using textures with the exact same resolution.	Directory	Value of type ‘Directory’	Yes
UseAlphaChannel	If true, include transparency information in the loaded textures, if there is any. If false, all loaded textures will be converted to RGB format. This setting can be used if you have textures with transparency, but do not need the transparency information. This may be the case when using additive blending, for example. Converting the files to RGB on load may then reduce the memory footprint and/or lead to some optimization in terms of rendering speed.	Boolean	Value of type ‘Boolean’	Yes

Asset Examples

Basic

This example creates a point cloud that supports interpolation. The dataset is split up into 10 objects, so that every tenth row represents a new position for an item at a step in the interpolation.

local Node = {
  Identifier = "RenderableInterpolatedPoints_Example",
  Renderable = {
    Type = "RenderableInterpolatedPoints",
    -- The dataset here is just a linearly expanding dataset, where the points move in
    -- a straight line
    File = asset.resource("data/interpolation_expand.csv"),
    -- Specify how many objects the rows in the dataset represent. Here, the dataset is
    -- consists of 10 objects with positions at 6 different time steps. This information
    -- is required
    NumberOfObjects = 10
  },
  GUI = {
    Name = "Basic",
    Path = "/Examples/RenderableInterpolatedPoints"
  }
}

asset.onInitialize(function()
  openspace.addSceneGraphNode(Node)
end)

asset.onDeinitialize(function()
  openspace.removeSceneGraphNode(Node)
end)

Smoother Interpolation (Spline-based)

Example of interpolating points with spline-based interpolation for the position. This leads to smoother transitions at the nodes of the interpolation.

local Node = {
  Identifier = "RenderableInterpolatedPoints_Example_Spline",
  Renderable = {
    Type = "RenderableInterpolatedPoints",
    -- Using a random walk dataset, to get movement in some different directions
    File = asset.resource("data/interpolation_randomwalk.csv"),
    -- Specify how many objects the rows in the dataset represent. Here, the dataset is
    -- consists of 10 objects with positions at 6 different time steps
    NumberOfObjects = 10,
    Interpolation = {
      -- Smoothen transitions between two different sets of points, by
      -- using a spline based interpolation of the points
      UseSplineInterpolation = true
    },
    -- Reduce the scale of the points a bit compared to default, so we see them more clearly
    SizeSettings = {
      ScaleExponent = 3.0
    }
  },
  GUI = {
    Name = "Spline (Smoother)",
    Path = "/Examples/RenderableInterpolatedPoints"
  }
}

asset.onInitialize(function()
  openspace.addSceneGraphNode(Node)
end)

asset.onDeinitialize(function()
  openspace.removeSceneGraphNode(Node)
end)

Interpolated Points with Color Mapping

Example of interpolating points with a color map. The data value used for the coloring will also be interpolated, leading to the points changing color throughout the interpolation.

--
-- Note that the color map is loaded from another asset. This is a utility asset that
-- includes some common color maps for general usage.

local colormaps = asset.require("util/default_colormaps")

local Node = {
  Identifier = "RenderableInterpolatedPoints_Example_ColorMapped",
  Renderable = {
    Type = "RenderableInterpolatedPoints",
    -- The dataset here is just a linearly expanding dataset, where the points move in
    -- a straight line
    File = asset.resource("data/interpolation_expand.csv"),
    -- Specify how many objects the rows in the dataset represent. Here, the dataset is
    -- consists of 10 objects with positions at 6 different time steps
    NumberOfObjects = 10,
    Coloring = {
      ColorMapping = {
        -- For this example, we are using one of the example colormaps "Viridis"
        File = colormaps.Uniform.Viridis
      }
    },
    -- Reduce the scale of the points a bit compared to default, so we see them more clearly
    SizeSettings = {
      ScaleExponent = 3.5
    }
  },
  GUI = {
    Name = "Color Mapped",
    Path = "/Examples/RenderableInterpolatedPoints"
  }
}

asset.onInitialize(function()
  openspace.addSceneGraphNode(Node)
end)

asset.onDeinitialize(function()
  openspace.removeSceneGraphNode(Node)
end)