final class DisplacementMapFilter
package openfl.filters
extends BitmapFilter
Available on all platforms
The DisplacementMapFilter class uses the pixel values from the specified BitmapData object (called the displacement map image) to perform a displacement of an object. You can use this filter to apply a warped or mottled effect to any object that inherits from the DisplayObject class, such as MovieClip, SimpleButton, TextField, and Video objects, as well as to BitmapData objects. The use of filters depends on the object to which you apply the filter:
- To apply filters to a display object, use the
filtersproperty of the display object. Setting thefiltersproperty of an object does not modify the object, and you can remove the filter by clearing thefiltersproperty. - To apply filters to BitmapData objects, use the
BitmapData.applyFilter()method. CallingapplyFilter()on a BitmapData object takes the source BitmapData object and the filter object and generates a filtered image.
If you apply a filter to a display object, the value of the
cacheAsBitmap property of the display object is set to true. If you
clear all filters, the original value of cacheAsBitmap is restored.
The filter uses the following formula:
dstPixel[x, y] = srcPixel[x + ((componentX(x, y) - 128) * scaleX) / 256, y + ((componentY(x, y) - 128) * scaleY) / 256)where componentX(x, y) gets the componentX property color value from
the mapBitmap property at (x - mapPoint.x ,y - mapPoint.y).
The map image used by the filter is scaled to match the Stage scaling. It is not scaled when the object itself is scaled.
This filter supports Stage scaling. However, general scaling, rotation,
and skewing are not supported. If the object itself is scaled (if the
scaleX and scaleY properties are set to a value other than 1.0), the
filter effect is not scaled. It is scaled only when the user zooms in on
the Stage.
Constructor
new(?mapBitmap:BitmapData, ?mapPoint:Point, componentX:Int = 0, componentY:Int = 0, scaleX:Float = 0.0, scaleY:Float = 0.0, mode:DisplacementMapFilterMode = WRAP, color:Int = 0, alpha:Float = 0.0)
Initializes a DisplacementMapFilter instance with the specified parameters.
Parameters:
mapBitmap | A BitmapData object containing the displacement map data. |
|---|---|
mapPoint | A value that contains the offset of the upper-left corner of the target display object from the upper-left corner of the map image. |
componentX | Describes which color channel to use in the map image to displace the x result. Possible values are the BitmapDataChannel constants. |
componentY | Describes which color channel to use in the map image to displace the y result. Possible values are the BitmapDataChannel constants. |
scaleX | The multiplier to use to scale the x displacement result from the map calculation. |
scaleY | The multiplier to use to scale the y displacement result from the map calculation. |
mode | The mode of the filter. Possible values are the DisplacementMapFilterMode constants. |
color | Specifies the color to use for out-of-bounds
displacements. The valid range of displacements is
0.0 to 1.0. Use this parameter if |
alpha | Specifies what alpha value to use for out-of-bounds
displacements. It is specified as a normalized value
from 0.0 to 1.0. For example, .25 sets a
transparency value of 25%. Use this parameter if
|
Variables
alpha:Float
Specifies the alpha transparency value to use for out-of-bounds
displacements. It is specified as a normalized value from 0.0 to 1.0.
For example, .25 sets a transparency value of 25%. The default value
is 0. Use this property if the mode property is set to
DisplacementMapFilterMode.COLOR.
color:Int
Specifies what color to use for out-of-bounds displacements. The valid
range of displacements is 0.0 to 1.0. Values are in hexadecimal
format. The default value for color is 0. Use this property if the
mode property is set to DisplacementMapFilterMode.COLOR.
componentX:Int
Describes which color channel to use in the map image to displace the
x result. Possible values are BitmapDataChannel constants:
BitmapDataChannel.ALPHA
BitmapDataChannel.BLUE
BitmapDataChannel.GREEN
BitmapDataChannel.RED
componentY:Int
Describes which color channel to use in the map image to displace the
y result. Possible values are BitmapDataChannel constants:
BitmapDataChannel.ALPHA
BitmapDataChannel.BLUE
BitmapDataChannel.GREEN
BitmapDataChannel.RED
mapBitmap:BitmapData
A BitmapData object containing the displacement map data.
Throws:
TypeError | The BitmapData is null when being set |
|---|
mapPoint:Point
A value that contains the offset of the upper-left corner of the target display object from the upper-left corner of the map image.
Throws:
TypeError | The Point is null when being set |
|---|
mode:DisplacementMapFilterMode
The mode for the filter. Possible values are DisplacementMapFilterMode
constants:
DisplacementMapFilterMode.WRAP — Wraps the displacement value to
the other side of the source image.
DisplacementMapFilterMode.CLAMP — Clamps the displacement value
to the edge of the source image.
DisplacementMapFilterMode.IGNORE — If the displacement value is
out of range, ignores the displacement and uses the source pixel.
DisplacementMapFilterMode.COLOR — If the displacement value is
outside the image, substitutes the values in the color and alpha
properties.
Throws:
ArgumentError | The mode string is not one of the valid types |
|---|---|
TypeError | The String is null when being set |