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Element Icon Random Dot Motion
Category: Stimulus Generators AddIn: Visual Kernels
Creator: OkazoLab Scope: Parent event
Owns Snippets: None Usage: Stimulus screen


NameDescription                              ConstraintsTypeOn
Patch Appearance
Background Color        Defines the background color of the generated random motion patch                stColor         
Patch Shape        Defines the shape of the generated motion patch                GaborP..         
Dot Density        Defines the density of dots in the generated motion patch. The value affects the Dot Number value                Double         
Dot Number        Returns a number of dots in the generated motion patch. The number depends on the dot density and the patch shape                Int32         
Reset Patch Now        Runtime commands that resets the RDM patch by reshuffling dot positions. To invoke the command, assign 'true' in snippets                Boolean         
Dot Appearance
Dot Color        Defines the color of a single motion dot                stColor         
Dot Size        Defines the size of a single motion dot                clSize         
Dot Shape        Defines the shape of a single motion dot, when its size greater than 1 pixel                GaborP..         
Motion Settings
Motion Type        Defines the motion type in the generated patch                enMoti..         
Motion Coherence        Defines a percentage of coherently moving dots in the patch, from 0 to 100                Double         
Motion Direction        Defines the direction of motion in degrees                Double         
Motion Speed        Defines the motion speed in pixels per step                Double         
Interleaved Sets Number        Defines the number of uncorrelated dot sets that are interleaved in a sequence of generated motion frames. The commonly used values are either 1 or 3.                Int32         
Max Dot Lifetime        Defines the maximal lifetime (in frames) of the coherently moving dots. If the maximal life time is reached, the moving dot is forced to random reallocation within a patch. Zero value means the infinite lifetime                Int32         
Reposition Rule        Defines the reposition rule for the incoherently moving dots. If the random walk mode is selected, the dot moves in a random direction with the same motion speed. If the random position mode is selected, the noise dots are just randomly reallocated within the patch.                enRepo..         
Min Frame Duration        Defines the minimal duration (ms) between consecutive motion frames. The zero value denotes that motion frames will be rendered as fast as possible, usually on each monitor refresh cycle.                clTime         
Central Diffusion        Defines the central diffusion for the origin of the outward radial motion in percentages to the total patch size. The value must not greater than zero                Double         
Visual Appearance
Alpha Masking        Defines, whether the visual content is used to create an opacity mask on the event surface. If masking is on, the content's pixel luminance (or, its inverse) defines transparency within element's viewport. The alpha masking allows, for example, create transparent holes on the event surface.                Int32         
AntiAliasing        if true, the rendered content will be antialiased for smoother visual appeariance. If false, rendering will be authentic to its source, e.g. a bitmap.                Boolean         
Position        Defines a position of the rendering viewport on the screen                clPoint         
Size        Defines a size of the element's rendering viewport on the screen                clSize         
Z Order        Indicates Z Order of the element on the given event                Int32         
Pivot Point        Defines alignment of the pivot point (or, element's position) relative to element's rendering area. The pivot point sets the center of element's rotation and scale directions.                stAlig..         
Visible        Defines whether the element is visible                Boolean         
Rotation        Rotation angle in degrees                Double         
Transparent Color        The color of the original pixels of rendered content that will be set as transparent                stColor         
Transparent Tolerance        Tolerance ratio for choosing colors that become transparent. Zero means that effect is not applied, 1 denotes that all colors will become trasparent                Int32         
Color Mask        Produces 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 dont change the original pixels                stColor         
Opacity        Opacity of the rendered content                Int32         
Contrast        Contrast of the rendered content                Int32         
Brightness        Brightness the rendered content                Int32         
Saturation        Saturation of the rendered content                Double         
Pixelation        Pixelation of the rendered content                Int32         
Blurring        The radius used in the gaussian blur of rendered content, as a pixel-based factor. The default is 0 which means no blurring.                Int32         
Scrambling                        Double         
Scrambling Grid Size        Defines a size of the scrambling grid                clSize         
Positional Jitter
Reset Jitter Now        Runtime command that resets the positional jitter.                Boolean         
Current Jitter        Returns the current jitter                clPoint         
Jitter Range        Defines a possible range for the random jitter. The range is centered to the position of the element.                clSize         
Test Jitter        Click to test the current jitter                Boolean         
Is Enabled        If set to false the element is completely omitted when the experiment is run                Boolean         
Title        Title 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.


Example of Random-dot motion element

Example of Random-dot motion element

Snapshot 2

Snapshot 2

Practical Use

Technique 1

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Technique 2

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


  Name Size
- Random-Dot-Motion-Element-Icon.png 5.02 KB

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