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Category: AddIn: Base Elements
Creator: OkazoLab Team Scope: Parent Event
Owns Snippets: no Usage: Runtime Screen,Snippets


Generic Properties

NameDescriptionAttributesValue TypeUpon Change
Dot Pattern
Dot DensityThe requested proportion of the all visible dots to the total number of dots in element's rendering area. Double
Lookup Map SizeThe size of the lookup map. Use value larger than the rendering area of the given element. Larger lookup map increase non-periodicity of the dot motion clSize
Allow Dot ClustersIndicates whether clusters of two or more dots are allowed. If false, all visible dots will be isolated but the actual dot density may be decreased. Boolean
Lookup indexIndex of the random lookup map. If value is 0 then an automatic time dependent index is used. Otherwise, the value has to be a positive integer. Int32
Background colorBackground color such that its brightness (B) is used to define the luminance of element's background. stColor
Dot colorForeground color such that its brightness (B) is used to define dot luminance stColor
Show Lookup BordersIndicates whether the left and top borders of the lookup map are shown being superimposed over the dots. Use for debugging purposes. Boolean
Motion CoherenceProportion of the dots coherently moving in a single direction Double
Motion StepThe pixel distance of one step of the coherent motion. Can be less than 1 for slow motion Double
Motion AngleDirection of the coherent motion in degrees (0..360). Double
Noise LookupLookup position on the map A representing the noise dots Point
Motion LookupLookup position on the map B containing coherently moving dots Point
Make NoiseRuntime action. Boolean
Make MotionRuntime action. Boolean

+=== Properties inherited from clVisualElement ===
NameDescriptionConstraintsValue TypeUpon Runtime Change
Alpha MaskingDefines whether the visual content rendered by this element will be used as an opacity mask which is applied onto the given event surface. The active opacity mask allows one to expose pixels of the parent event surface through a solid background of the given event. If the value is true, the darker pixels of the content will make more transparent holes on the entire event surface.Boolean
AntiAliasingIf true, the rendered content will be anti-aliased for smoother visual appearance. If false, rendering will be authentic to its source, e.g. a bitmap. Boolean
PositionDefines the position of the element viewport on the screen. The position can be set in any of three coordinate systems: a) pixels, b) polar, c) central. clPoint
SizeDefines the size of the element viewport on the screen. The size can be set in any of three coordinate systems: a) pixels, b) visual degrees, c) 'relative-to-screen' size. clSize
Z OrderIndicates the current depth order of the element viewport on the surface of the parent event. The greatest number corresponds to the top position. The order can be changed by moving the element up and down in the element list.Int32
Pivot PointDefines the pivot point (coordinate and the rotation centers) within the element viewport. stAlignment or Int32
VisibleDefines whether the element is currently visible on the event surface. The property is convenient for switching visual content on and off. Boolean
RotationDefines the rotation angle (in degrees) of element viewport relative to the its pivot point. Double in the range 0..360
Transparent ColorThe color of the original pixels of rendered content that will be set as transparent. stColor
Transparency ToleranceTolerance ratio for choosing colors that become transparent. Zero means that effect is not applied, 1 denotes that all colors will become trasparent. Int32, range (0..100)
Color MaskProduces a multiplicative combination of the original pixels and the selected mask color (except the alpha channel). The effect emulates a look through a colored glass. White or transparent mask color doesn't change the original pixels. stColor
OpacityOpacity of the rendered content. Int32, range (0..100)
ContrastContrast of the rendered content. Int32, range (-100..100)
BrightnessDefines the brighness of the rendered content. Int32, range (-100..100)
SaturationSaturation of the rendered content. Double
PixelationDefines the pixel scale of the rendering. Int32, range (0..100)
BlurringThe radius used in the gaussian blur of rendered content, as a pixel-based factor. The default is 0 which means no blurring. Int32
Reset JitterSet to true at runtime to reset the current positional jitter.Boolean, set true for action
Current JitterJitter range, in pixels (non inclusive)..clSize
Jitter RangeJitter range, centered at the original position of the element.. clSize

+=== Properties inherited from clElement === Inherited properties of clElement
NameDescriptionConstraintsValue TypeUpon Change
Is EnabledIf set to false the element is completely omitted when the experiment is run.Boolean
TitleTitle of the element.String

Random Dot Motion element generates animated RDM patches controlled by a flexible set of parameters.


Random-dot motion element generates a sequence of 2D frames that can make up a random dot motion patten. The selected fraction of all dots can be set to move in a single direction, thus producing a coherent motion. Some examples how this stimulus looks like during the experiment can be found here.


Example of Random-dot motion element

Example of Random-dot motion element

Snapshot 2

Snapshot 2

Practical Use

Technique 1

  1. Step 1
  2. Step 2

Technique 2

  1. Step 1
  2. Step 2

 // Check the trial outcome. Result and RT just other user variables
// insert code snippet here..


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