Passthrough lookup tables (LUTs) transform the colors that passthrough displays. You can use them to evoke a certain style, such as tinting everything red when you are low on health, or to emulate a lighting environment, like dimming lights when a movie starts.

Passthrough LUTs are represented by a 3D color "cube" with the dimensions of 16x16x16 or 32x32x32 representing input RGB values. Each of the 16^3 or 32^3 values are mapped to a 32-bit RGBA color value (each color channel being 0-255).

See our guide on Passthrough LUTs for more details.

Usage:

// initialize lut
val lut = Lut()
for (r in 0..15) {
    for (g in 0..15) {
        for (b in 0..15) {
            // set a mapping color for each RGB value in the (0-15)^3 range
            lut.setMapping(r, g, b, r * 4 + r / 4, g * 4 + g / 4, b * 4 + b / 4)
        }
    }
}
// alternatively, for a simple scaling, you can use `Lut.fromScale(Vector3)`
val lut = Lut.fromScale(Vector3(0.25f))
// loading from a bitmap is possible too
val lut = Lut.fromBitmap(BitmapFactory.decodeFile("lut.png"))
// finally, apply it to the passthrough
scene.setPassthroughLUT(lut)

Signature

class Lut(val dimension: Int = 16)

Constructors

Lut ( dimension )

Signature

constructor(dimension: Int = 16)

Parameters

                                                    dimension:
Int
            

The dimension of the LUT (16 or 32), defaults to 16.

Returns

Lut

Properties

dimension : Int

[Get]

The dimension of the LUT (16 or 32), defaults to 16.

Signature

val dimension: Int = 16

Functions

getTable ()

Returns a 1D array representation of the 3D color lookup table.

Signature

fun getTable(): IntArray

Returns

                IntArray
            

The internal table pixels.

setMapping ( srcR , srcG , srcB , toR , toG , toB )

Sets a specific RGB to be set to a different RGB value in the LUT.

Signature

fun setMapping(srcR: Int, srcG: Int, srcB: Int, toR: Int, toG: Int, toB: Int)

Parameters

                                                    srcR:
Int
            

The red component of the source color (less than dimensions).

                                                    srcG:
Int
            

The green component of the source color (less than dimensions).

                                                    srcB:
Int
            

The blue component of the source color (less than dimensions).

                                                    toR:
Int
            

The red component of the destination color (8-bit).

                                                    toG:
Int
            

The green component of the destination color (8-bit).

                                                    toB:
Int
            

The blue component of the destination color (8-bit).

Throws

                Exception
            

If the source color is out of range based on the dimensions.

Companion Object

Companion Object Functions

fromBitmap ( bitmap )	Creates a LUT object from a Bitmap loaded from disk. The bitmap is a 2D representation of the 3D LUT and must be 256x16 or 1024x32 pixels. Signature fun fromBitmap(bitmap: Bitmap): Lut? Parameters bitmap: Bitmap The bitmap to create the LUT from. Returns Lut? The created LUT object or null if an error occurred.
fromScale ( scale )	Creates a LUT where RGB are scaled component-wise by the given XYZ scale. Signature fun fromScale(scale: Vector3): Lut Parameters scale: Vector3 The scale to apply to the RGB values. Returns Lut The created LUT object.