Parameter Data Usage
The parameter data usage atom defines the intended use of the data in the parameter. This information can be used by your application to provide a more appropriate user interface for a parameter or group of parameters. For example, if your application knows that a set of four long integer values actually represent a rectangle, it can present a graphical display of the rectangle, rather than simply displaying four numeric input fields.
The data in this atom is stored in the following data structure:
typedef struct
{
OSType usageType;
} ParameterDataUsage;
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usageType
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This field defines the actual use that a parameter or group of parameters. It can take one of the following values:
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kParameterUsagePixels
- The parameters in the group contain a set of pixels.
-
-
kParameterUsageRectangle
-
- The parameters in the group contain the top-left and bottom-right co-ordinates of a rectangle.
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kParameterUsagePoint
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- The parameters in the group contain the co-ordinates of a point.
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kParameterUsage3DPoint
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- The parameters in the group contain the X-Y-Z co-ordinates of a 3D point.
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kParameterUsage3by3Matrix
- The parameters in the group contain a 3x3 matrix
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of values.
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kParameterUsageDegree
-
s
- The parameter contains degrees.
-
kParameterUsageRadians
-
- The parameter contains radians.
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kParameterUsagePercent
-
- The parameter contains a percentage.
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kParameterUsageSeconds
-
- The parameter contains seconds.
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kParameterUsageMilliseconds
-
- The parameter contains milliseconds.
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kParameterUsageMicroseconds
- The parameter contains microseconds.
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The parameter data usage atom is optional.
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