gtk.Curve
Prev | The gtk Class Reference | Next

## gtk.Curve

gtk.Curve — allows direct editing of a curve.

## Synopsis

    class gtk.Curve(gtk.DrawingArea):
        gtk.Curve()
        def reset()
        def set_gamma(gamma)
        def set_range(min_x, max_x, min_y, max_y)
        def get_vector(size=-1)
        def set_vector(vector)
        def set_curve_type(type)

## Ancestry

    +-- gobject.GObject
      +-- gtk.Object
        +-- gtk.Widget
          +-- gtk.DrawingArea
            +-- gtk.Curve

## Implemented Interfaces

`gtk.Curve` implements `gtk.Buildable`

## gtk.Curve Properties

gtk.Object Properties

gtk.Widget Properties

"curve-type" | Read/Write | The curve type. One of linear (`gtk.CURVE_TYPE_LINEAR`), spline interpolated (`gtk.CURVE_TYPE_SPLINE`), or free-form (`gtk.CURVE_TYPE_FREE`).
"max-x" | Read/Write | The maximum possible value for X
"max-y" | Read/Write | The maximum possible value for Y
"min-x" | Read/Write | The minimum possible value for X
"min-y" | Read/Write | The minimum possible value for Y

## gtk.Curve Style Properties

gtk.Widget Style Properties

## gtk.Curve Signal Prototypes

gobject.GObject Signal Prototypes

gtk.Object Signal Prototypes

gtk.Widget Signal Prototypes

"curve-type-changed" | `def callback(`curve`, `widget`, `user_param1`, `...`)`

## Description

### Note

`gtk.Curve` is deprecated in GTK+ 2.20 and PyGTK 2.22 since it is too specialized.

The `gtk.Curve` widget allows the user to edit a curve covering a range of values. It is typically used to fine-tune color balances in graphics applications like the Gimp. The `gtk.Curve` widget has 3 modes of operation - spline, linear and free. In spline mode the user places points on the curve which are automatically connected together into a smooth curve. In linear mode the user places points on the curve which are connected by straight lines. In free mode the user can draw the points of the curve freely, and they are not connected at all.

## Constructor

        gtk.Curve()

Returns : | a new gtk.Curve object

Creates a new `gtk.Curve` object

## Methods

### gtk.Curve.reset

        def reset()

The `reset`() method resets the curve to a straight line from the minimum x and y values to the maximum x and y values (i.e. from the bottom-left to the top-right corners). The curve type is not changed.

### gtk.Curve.set_gamma

        def set_gamma(gamma)

`gamma` : | the gamma value

The `set_gamma`() method recomputes the entire curve using the value in `gamma`. A gamma value of 1 results in a straight line. Values greater than 1 result in a curve above the straight line. Values less than 1 result in a curve below the straight line. The curve type is changed to `gtk.CURVE_TYPE_FREE`.

### gtk.Curve.set_range

        def set_range(min_x, max_x, min_y, max_y)

`min_x` : | the new minimum x value
`max_x` : | the maximum x value.
`min_y` : | the new minimum y value
`max_y` : | the maximum y value.

The `set_range`() method sets the "min-x", "min-y", "max-x" and "max-y" properties from`min_x`, `min_y`,`max_x`, and `max_y`. The curve is also reset with a call to `reset`().

### gtk.Curve.get_vector

        def get_vector(size=-1)

`size` : | the number of points to return or -1 to return all the points in the curve.
Returns : | a tuple containing the points

The `get_vector`() method returns a tuple of points representing the curve. The number of points to return is specified by `size`; if `size` is -1 all the points in the curve are returned.

### gtk.Curve.set_vector

        def set_vector(vector)

`vector` : | a list or tuple containing the points of the curve

The `set_vector`() method sets the curve using the points in `vector`. The curve type is set to `gtk.CURVE_TYPE_FREE`.

### gtk.Curve.set_curve_type

        def set_curve_type(type)

`type` : | the new curve type: `gtk.CURVE_TYPE_LINEAR`, `gtk.CURVE_TYPE_SPLINE` or `gtk.CURVE_TYPE_FREE`

The `set_curve_type`() method sets the "curve-type" property with the value of `type`. The curve type must be one of `gtk.CURVE_TYPE_LINEAR`, `gtk.CURVE_TYPE_SPLINE` or `gtk.CURVE_TYPE_FREE`. The curve will remain unchanged except when changing from a free curve to a linear or spline curve, in which case the curve will be changed as little as possible.

## Signals

### The "curve-type-changed" gtk.Curve Signal

        def callback(curve, user_param1, ...)

`curve` : | the curve that received the signal
`user_param1` : | the first user parameter (if any) specified with the `connect`() method
`...` : | additional user parameters (if any)

The "curve-type-changed" signal is emitted when the curve type has been changed. The curve type can be changed explicitly with a call to `set_curve_type`(). It is also changed as a side-effect of calling `reset`() or `set_gamma`()

Prev | Up | Next
gtk.Container | Home | gtk.Dialog