Shapes

Shapes describe the geometric form of a region in a scene.

All shapes have two dimensions called x and y. They are located relative to the position of the region. The shape is alligned to the region by its leftmost and topmost point.

Circle

Item type	Circle
Description	a shape where all points of the border have the same distance from a center.
Action	-
Condition	-

Key	Type	Default	Description
center	point		the center
radius	int		the radius

Ellipse

Item type	Ellipse
Description	a shape where all points of the border have the same distance from two centers.
Action	-
Condition	-

Key	Type	Default	Description
center1	point		first center
center2	point		second center
radius	int		radius

Note: The radius of an ellipse is defined here as the sum of the distances between a point of the border and both centers.

Rectangle

Item type	Rectangle
Description	a shape with four sides that are parallel to the dimensions
Action	-
Condition	-

Key	Type	Default	Description
position	point	(0,0)	the upper left corner
size	point		width and height

Polygon

Item type	Polygon
Description
Action	-
Condition	-

Key	Type	Default	Description
points	[point]		the end points of the lines

Note: Usually, polygons consist of at least three points. Single points and lines with two points are valid, but will be very difficult to find in a scene.

WindowsRegion

Item type	WindowsRegion
Description	a region in the Windows format
Action	-
Condition	-

Key	Type	Default	Description
region	[byte]		a region handle of Windows

Note: The bytes in the attribute region have to be retrieved by the Windows function DWORD GetRegionData(HRGN, DWORD, LPRGNDATA).

ColourMap

Item type	ColourMap
Description	a shape defined by the colour in an image
Action	-
Condition	-

Key	Type	Default	Description
image	Image		an image
colour	colour		the colour to define the region

With colour maps, a single image may be used to define several regions. Each region has the shape that is defined by one colour of the image. Unlike the geometrically defined shapes, this allows you to associate single pixels directly to a region. Thus, even complex and unusual shapes may be defined easily.

Combination

Item type	Combination
Description	a combination of several shapes
Action	-
Condition	-

Key	Type	Default	Description
combine	byte	+	the type of combination; see definitions for values
shapes	[Shapes]		a list of shapes to combine
offsets	[point]	[]	a list of offsets

The offsets change the relative position of the according shape. The list needs not to contain an offset for every shape (i.e. the list may be empty or shorter than the list of shapes).