A checkerboard pattern, including option for flicker.
If an element can end on its own, you don't need to set end conditions for it in property end (unless you want it to maybe end earlier).
No—runs until a condition you set in property end.
You can vary or allow the subject to adjust the following input properties of an object of this type in real time when it's running. If you need to make other properties adjustable, you can edit the element type code—see Element Type Programming Manual.
Default: square with sides 10 deg
A number that is side length for a square checkerboard, or a vector [width height] for a rectangle (deg).
Default: 20 square checks in the checkerboard width
Or a vector [n_x n_y] setting number of checks in the width/height directions independently. You can use this if you want non-square checks.
Default: immediate check in quadrant 1 = light
0/1 setting the initial pattern: 0 = check immediately right and below element display center = dark, 1 = light. Note currently the checkerboard is always centered at element position, with the corners of four checks at that point. Element position can be set in property position.
Defaults: meanIntensity = 0.5, amplitude = 0.5
Also set one of:
amplitude is max intensity − mean intensity.
contrast is Michelson contrast, amplitude / mean intensity. If you set contrast, mean intensity must be > 0.
It's possible to set a combination of these properties that causes the checkerboard to clip at intensity 0 or 1. See record properties maxAmplitude and maxContrast below.
A 1×3 RGB vector with numbers between 0–1. This defines the color at intensity = 1. Color at intensity = 0 is <cd>[0 0 0]<cd>. Color at all other intensities is linearly interpolated between the two.
Default: no flicker
Frequency of switching between dark–light (cycles/sec). 0 = no flicker.
PsychBench uses record properties to record information during experiments. You can't set record properties but you can see them in experiment results by listing them input property report.
Maximum amplitude and contrast where intensity would clip at 0 or 1, whichever is reached first, given the set mean intensity.