Programming Reference:ImageStimulus Class

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Location

src/shared/modules/application/stimuli

Synopsis

The ImageStimulus class provides a VisualStimulus that displays an image loaded from a file.

Properties

string File (rw)

A relative or absolute path to an image file. When relative, the path is interpreted relative to the application module's working directory at startup.

enum RenderingMode (rw)

One of GUI::RenderingMode::Transparent or GUI::RenderingMode::Opaque. When Transparent, the image's bottom leftmost pixel is taken to represent its background, and pixels of this color are not drawn, allowing objects below the ImageStimulus to appear.

Inherited from VisualStimulus

enum PresentationMode (rw)

This property determines the way a stimulus is presented. It is one of the following:

ShowHide
The stimulus is initially invisible, and visible while being presented.
Intensify
During presentation, the contrast of the stimulus is increased.
Grayscale
During presentation, the stimulus is displayed in grayscale rather than color.
Invert
During presentation, the stimulus appears color-inverted.
Dim
During presentation, the contrast of the stimulus is reduced.
HideShow
The stimulus is initially visible, and invisible while being presented.

float DimFactor (rw)

Determines the contrast ratio between presentation and non-presentation in Dim and Intensify modes. In Intensify mode, values greater 1 will result in a brighter appearance during presentation; in Dim mode, values greater 1 will result in a darker appearance during presentation. Due to saturation effects, the result may not be as expected.

Inherited from GraphObject

GraphDisplay Display (r)

The GraphDisplay object that was specified when the object was created.

bool Visible (r)

True if the object is visible, false if it is hidden. Use the Hide() and Show() methods to set this property.

float ZOrder (rw)

Determines the order in which GraphObjects are drawn. GraphObjects with smaller values of ZOrder are drawn on top of those with larger values, hiding these.

enum AspectRatioMode (rw)

One of the following options:

AdjustNone
No adjustment is made.
AdjustWidth
The object's width is adapted to its contents, while keeping its height constant.
AdjustHeight
The object's height is adapted to its contents, keeping its width constant.
AdjustBoth
Both the object's height and width are adjusted to its content.

The exact behavior of aspect ratio adjustment depends on the object's type. E.g., for bitmap images, AdjustBoth will size the image such that one image pixel corresponds to one screen pixel; AdjustHeight and AdjustWidth will adjust such that the original aspect ratio is preserved.

GUI::Rect DisplayRect (rw)

The bounding rectangle of the space that is occupied by the object. This is given in coordinates relative to the size of the object's GraphDisplay; there, the upper left corner corresponds to (0,0), the lower right corner to (1,1). When a GraphObject is created, its display rectangle is empty.

Methods

Inherited from GraphObject

Show()

Makes the object visible. Initially, objects are created in visible state.

Hide()

Makes the object invisible.

Invalidate()

Invalidates the object's bounding rectangle, i.e. marks it as needing to be repainted. Typically, this function is called from a derived class, indicating that a change in object properties has occurred that requires a repaint.

Paint()

Asks an object to paint itself by calling its OnPaint event handler.

Change()

Notifies an object of a change in display properties by calling its OnChange event handler.

bool Click(GUI::Point)

Tests whether the specified point is inside an object's bounding rectangle, and calls its OnClick event handler if this is the case.

See also

Programming Reference:VisualStimulus Class, Programming Reference:GraphObject Class