PropFloat Class Reference
Float properties represent a feature whose value is a floating-point number. More...
Inheritance diagram for PropFloat:
![](common/img/classic4_prop_float.png)
Public Member Functions
PropFloatRepresentation | representation (Error &err=Error::Default()) const Returns the suggested representation for this float property. |
std::string | unit (Error &err=Error::Default()) const Returns the unit of this float property. |
PropDisplayNotation | displayNotation (Error &err=Error::Default()) const Returns a suggested display notation to use when displaying the float property's value. |
int64_t | displayPrecision (Error &err=Error::Default()) const Returns a suggested number of significant digits to use when displaying the float property's value. |
bool | setValue (double value, Error &err=Error::Default()) Changes the value of this property. |
double | getValue (Error &err=Error::Default()) const Reads the current value of this property. |
double | minimum (Error &err=Error::Default()) const Returns the minimum value accepted by this property. |
double | maximum (Error &err=Error::Default()) const Returns the maximum value accepted by this property. |
PropIncrementMode | incrementMode (Error &err=Error::Default()) const Returns how this float property restricts which values are valid between its minimum and maximum value. |
double | increment (Error &err=Error::Default()) const Returns the step size for valid values accepted by this float property. |
std::vector< double > | validValueSet (Error &err=Error::Default()) const Returns the valid value set for this property. |
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Property ()=default Creates an invalid object. |
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bool | is_valid () const noexcept Checks whether this property is a valid object. |
bool | operator== (const Property &other) const noexcept Checks whether a property object refers to the same property as another property object. |
bool | operator!= (const Property &other) const noexcept Checks whether a property object refers to a different property as another property object. |
bool | operator< (const Property &other) const noexcept Provides an ordering of property objects. |
PropType | type (Error &err=Error::Default()) const Returns the type of the property. |
std::string | name (Error &err=Error::Default()) const Returns the name of the property. |
bool | isAvailable (Error &err=Error::Default()) const Checks whether a property is currently available. |
bool | isLocked (Error &err=Error::Default()) const Checks whether a property is currently locked. |
bool | isLikelyLockedByStream (Error &err=Error::Default()) const Tries to determine whether a property is locked because a data stream is active. |
bool | isReadOnly (Error &err=Error::Default()) const Checks whether a property is read-only. |
PropVisibility | visibility (Error &err=Error::Default()) const Returns a visibility hint for the property. |
std::string | displayName (Error &err=Error::Default()) const Returns the display name of the property. |
std::string | tooltip (Error &err=Error::Default()) const Returns a tooltip for the property. |
std::string | description (Error &err=Error::Default()) const Returns a description for the property. |
PropCommand | asCommand (Error &err=Error::Default()) const Converts this property into a PropCommand. |
PropInteger | asInteger (Error &err=Error::Default()) const Converts this property into a PropInteger. |
PropBoolean | asBoolean (Error &err=Error::Default()) const Converts this property into a PropBoolean. |
PropFloat | asFloat (Error &err=Error::Default()) const Converts this property into a PropFloat. |
PropString | asString (Error &err=Error::Default()) const Converts this property into a PropString. |
PropEnumeration | asEnumeration (Error &err=Error::Default()) const Converts this property into a PropEnumeration. |
PropEnumEntry | asEnumEntry (Error &err=Error::Default()) const Converts this property into a PropEnumEntry. |
PropRegister | asRegister (Error &err=Error::Default()) const Converts this property into a PropRegister. |
PropCategory | asCategory (Error &=Error::Default()) const Converts this property into a PropCategory. |
NotificationToken | eventAddNotification (NotificationHandler cb, Error &err=Error::Default()) Registers a new property notification event handler. |
bool | eventRemoveNotification (NotificationToken token, Error &err=Error::Default()) Unregisters a previously registered property notification event handler. |
bool | isSelector (Error &err=Error::Default()) const Indicates whether this property's value changes the meaning and/or value of other properties. |
std::vector< Property > | selectedProperties (Error &err=Error::Default()) const Returns the list of properties whose values' meaning depend on this property. |
Additional Inherited Members
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using | NotificationHandler = std::function< void(Property &prop)> Function prototype for property notification event handlers. |
using | NotificationToken = void * Represents a registered callback. |
Detailed Description
Float properties represent a feature whose value is a floating-point number.
Common examples for a float properties are AcquisitionFrameRate
, ExposureTime
or Gain
.
A float property can limit the range of valid values. The range of possible values can be queried by calling PropFloat::minimum() and PropFloat::maximum().
The possible values can be further restricted by an increment value or a set of value values. Check PropFloat::incrementMode(), PropFloat::increment() and PropFloat::validValueSet() for details.
A float property supplies hints that can be useful when creating a user interface:
- A representation (PropFloat::representation())
- A unit (PropFloat::unit())
- Display notation and precision (PropFloat::displayNotation(), PropFloat::displayPrecision())
PropFloat instances are created in two ways:
- By converting a Property known to be a command property using Property::asFloat()
- By directly querying a typed known property using PropertyMap::findFloat().
Member Function Documentation
◆ displayNotation()
|
inline |
Returns a suggested display notation to use when displaying the float property's value.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The suggested display notation for this property.
If an error occurred, this function returns a default representation. Check the err output parameter for details.
◆ displayPrecision()
|
inline |
Returns a suggested number of significant digits to use when displaying the float property's value.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The suggested display notation for this property.
If an error occurred, this function returns a default precision. Check the err output parameter for details.
◆ getValue()
|
inline |
Reads the current value of this property.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The current value.
If an error occurs, the function returns0
. Check the err output parameter for details.
- See also
- PropFloat::setValue()
◆ increment()
|
inline |
Returns the step size for valid values accepted by this float property.
The increment restricts the set of valid values for a float property. For example, if the property's minimum value is 0
, the maximum is 10
, and the increment is 0.5
, 0.25
is not a valid value for the property and will be rejected when trying to write it.
This function will fail if PropFloat::incrementMode() does not return PropIncrementMode::Increment.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The step size.
If an error occurs, the function returns0
. Check the err output parameter for details.
- See also
- PropInteger::incrementMode()
◆ incrementMode()
|
inline |
Returns how this float property restricts which values are valid between its minimum and maximum value.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- PropIncrementMode::Increment, if the property has a fixed step size between valid values.
PropIncrementMode::ValueSet if the property has a set of valid values.
PropIncrementMode::None if the property has no restrictions.
If an error occurs, the function returns PropIncrementMode::None. Check the err output parameter for details.
- See also
- PropFloat::increment()
- PropFloat::validValueSet()
◆ maximum()
|
inline |
Returns the maximum value accepted by this property.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The maximum value.
If an error occurs, the function returns0
. Check the err output parameter for details.
- See also
- PropFloat::minimum()
◆ minimum()
|
inline |
Returns the minimum value accepted by this property.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The minimum value.
If an error occurs, the function returns0
. Check the err output parameter for details.
- See also
- PropFloat::maximum()
◆ representation()
|
inline |
Returns the suggested representation for this float property.
The representation can be used as a hint when creating user interfaces.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The suggested representation of this property.
If an error occurred, this function returns a default representation. Check the err output parameter for details.
◆ setValue()
|
inline |
Changes the value of this property.
- Parameters
-
[in] value The new value to set [out] err Reference to an error handler. See Error Handling for details.
- Returns
true
on success, otherwisefalse
.
Check the err output parameter for details.
- See also
- PropFloat::getValue()
◆ unit()
|
inline |
Returns the unit of this float property.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- The unit of this property. The unit can be an empty string, if there is no unit for the property.
If an error occurred, this function returns an empty string. Check the err output parameter for details.
◆ validValueSet()
|
inline |
Returns the valid value set for this property.
This function will fail if PropFloat::incrementMode() does not return PropIncrementMode::ValueSet.
- Parameters
-
[out] err Reference to an error handler. See Error Handling for details.
- Returns
- A vector containing the set of valid values.
If an error occurs, the function returns an empty vector. Check the err output parameter for details.
- See also
- PropFloat::incrementMode()