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Event Icon Experiment
Category: Design object
Role: Scenario

Experiment Properties

NameDescriptionConstraintsValue Type
Elapsed TimeReturns the time passed since the start of the experiment in ms. This property can be used as a global timer in all code snippets across the experiment.clTime
Screen CloneReturns an auto-updating ImageSource object that contains a clone of the stimulus screen. The clone image is updated only with events that have the Screen Cloning property set to true (it is false by default). The ImageSource object can be used for data binding on the Status Screen, e.g. the XAML image element: "<Image Width='800' Height='600' Source='{Binding ScreenClone}/>" ImageSource
Save ScreenshotWhenever you want to make a screenshot of the current stimulus screen, assign a string containing a full file name to this property in snippets. The screenshot will be saved into the target file after the end of a snippet call. The format of the image file is defined by the extension of the file name: .bmp, .png or .jpg.String
Subevent IndexReturns an index of the currently active event on the root layer of the experiment. The property can be used for monitoring the event flow. This property also allows to control the event flow manually, bypassing the flow routes: when a new event index is assigned to it, the corresponding event will be immediately activated on the root layer.Int32
Stop KeyDefines a keyboard button for aborting the experiment run. The default stop button is Escape.Keys
Pause KeyDefines a keyboard button for pausing the experiment run. The default pause button is Pause.Keys
Abort RunRuntime commands that aborts the current experiment run at any moment, as the command is called in snippets. The command result is the same as pressing of the stop button, but the command can be invoked in code.Boolean
Is PausedDefines whether the experiment run is paused. Note that pausing does not stop the core timer in the experiment.Boolean
Display Settings
Display ModeOpens a window where you can define a display mode (pixel resolution, color depth and refresh mode) of the stimulus display. In that window you can also enter physical measures (display size and distance) that automate pixel-visual degrees conversion on the current experimental setup.
Default BackgroundDefines the default background color of all visual events in the experiment. If an event has the transparent background by design, the default color will be used to fill the background at runtime.stColor
Touchscreen ModeDefines whether mouse coordinates are collected only while the left mouse button is pressed. This mode is handy when participants are requested to maintain pressing on a touchscreen, while moving a finger. The mode allows the ROI elements to work with a touchscreen as with an eye-tracker.Boolean
Visual CompositionDefines whether off-screen surfaces of visual events are composed with CPU (software) or with GPU (hardware). The hardware composition mode is recommended for complex visual scenes or 3D, whereas the software mode is general safer and can be fastest for simple scenes. If you opt for speed, try both modes and check the composition and rendering times of events.Enum
Data Collection
ReportThe property provides an interface to Report- a default runtime mechanism for data storage in EventIDE. When you write a string value to the Report properly in code snippets, the value is added as a new line into the data report file. The collected strings can be viewed after an experiment is finished, or exported to into a text or Excel file.String
Report's column delimitersDefines what characters are regarded as column delimiters, when Report is exported into a formatted file, e.g. Excel. You can defines several characters, typing them in a sequence. By default, semicolon, comma and tab characters are regarded as delimiters.String
Auto Export FileDefines the name of a text file, into which the collected Report data is automatically exported on the end of experiment run. The auto export is done only, when the property value is not empty. The file name can be defined in snippets at runtime.String
Exclusive InputDefines whether the system input devices (e.g. keyboard or mouse) are accessed in the exclusive mode. If true, their input latencies can be shorter but all input is blocked for other programs.Boolean
Library CachingDefines whether some library materials, such as images, are cached in the memory prior to the experiment run. If true, visual rendering can significantly speed up by the cost of higher memory consumption.Boolean
Ahead LockDefines the duration of locking time interval, in ms, before onset of any event. During the lock interval all activities, like snippet calls, are blocked for sake of better timing accuracy of the event onset. The default value is 5ms, which is roughly equal to 1/2 of one monitor frame at 100Hz. The property can be modified at runtime.UInt64
VSyncDefines whether the onset of the visual events is synchronized with a start of the monitor's refresh pass. If the value is true, the visual changes are smooth and flicker free. However, the actual event durations may be longer (never shorter) than the requested duration. This property does not affect timing of the non-visual events.Boolean
Realtime PriorityDefines whether the program requests the "realtime" priority at runtime, for sake of best timing accuracy. The recommended value is true for the multi-core computers and false for the single-core computers.Boolean
Status Screen PriorityDefines a running priority of the Status Screen at runtime. Higher priority makes the status screen’s updates more frequent but may reduce overall timing accuracy in the experiment.Enum
Proxy CachingDefines whether the proxy variables are cached inside of code snippets. When true (default mode), changes to the proxy variables are applied only after the exit from a snippet. If false, the changes are applied immediately, as they are met in snippet code. Disabling the proxy caching may lead to more frequent proxy updates and, consequently, to a significant growth of snippets' execution times. The caching mode does not affect re-rendering after visual changes, because it is always performed after a snippet call.Boolean
Positional Input
Mouse DeviceDefines which pointer device provides the default system mouse input at runtimeenum
Mouse PointReturns a screen point that represents the most recent system mouse coordinates. The property value is refreshed on every Control Loop cycle. Writing to the property moves the mouse cursor into a new position.clPoint
Timing Statistics
Measured DurationReturns the total duration of the experiment (ms) after the experiment is completedclTime
Snippet TimesReturns the statistics of executions times (ms) for the root snippets (ones shown in the top row in the snippet panel). Statistics of a single snippet can be accessed by snippet's name, for example: 'clTime Time=(clTime) SnippetTimes"After Onset";' The snippet mush contain code to be included into the list.Dictionary
Control Loop IntervalReturns continuously re-measured time interval (ms) between two consecutive step of the experiment's control loop. If there are no going computational load or snippet calls in the experiment the interval is close to zero.clTime
Onset TimeReturns the time of the actual experiment onset in milliseconds since activation of the the global timer (the experiment duration also includes the preparation time passed before the onset).clTime


Experiment is a root object in the EventIDE logic that accommodates an experiment scenario, stimulus materials and user code. The experiment object has a set of editable properties that represent global settings, such as a screen resolution or a default background color. The experiment object and accommodated content are saved together in a single file recognizable by ".eve" extension.

Creating a new experiment

Creating a new experiment in EventIDE resembles creating a new document in other programs. Open the application menu and press 'New' item. Then you can chose whether you want to create a blank experiment or pick up one of templates in the Template gallery. A blank experiment contains one layer with a single event. Then you should build a scenario, load stimulus materials, write a code and, finally, run a designed task with participants. When you open one of experiment templates, you often need only to customize it for your task.

Reusing custom templates

When you repeatedly use the same paradigm in multiple studies, it might be a good idea to create your own reusable experiment template. Start with designing a base experiment that will be easy to customize later. The template can be incomplete and preliminary. Then go the Abstract ribbon tab and mark the experiment as template and optionally define its category, e.g. My Templates. Finally, save the experiment in any location under the main program folder (the Demos subfolder is recommended). The experiment template will now appear in the Template gallery in the Application menu.

Modifying the experiment properties

EventIDE GUI has has the dedicated HQ ribbon tab that shows all code in the current experiment and its property. As you navigate into the HQ tab, you can access and edit the experiment properties in the property panel on the right on the main window:
HQ ribbon tab and experiment properties

HQ ribbon tab and experiment properties

  Name Size
- experimenticon.png 4.66 KB
- HQPanel-sm.png 114.28 KB
- HQPanel.png 483.56 KB

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