- Qt 6.9
- Qt Quick 3D
- QML Types
- QtQuick3D.Particles3D
- LineParticle3D
- Qt Quick 3D | Commercial or GPLv3

# LineParticle3D QML Type

Line particle. More...

Import Statement: | `import QtQuick3D.Particles3D`
Since: | Qt 6.4
Inherits: | SpriteParticle3D

- List of all members, including inherited members

## Properties

- TexcoordMode : enumeration
- alphaFade : real
- eolFadeOutDuration : int
- length : real
- lengthDeltaMin : real
- lengthVariation : real
- scaleMultiplier : real
- segmentCount : int
- texcoordMode : TexcoordMode
- texcoordMultiplier : real

## Detailed Description

The LineParticle3D creates line shaped sprite particles.

The line is created from the path of the particle when it moves. The length of the line is specified either by the length parameter or the segment count and minimum delta between points. In latter case the length of the line may vary if the particles speed varies.

## Property Documentation

TexcoordMode : enumeration

Defines the texture coordinate mode of line particle.

Constant | Description
--- | ---
`LineParticle3D.Absolute` | Texture coordinates are specified relative to the world position.
`LineParticle3D.Relative` | Texture coordinates are specified relative to line first line point.
`LineParticle3D.Fill` | Texture coordinates are specified such that the texture fills the whole line.

alphaFade : real

This property holds the alpha fade factor of the line. The alphaFade value range is [0, 1]. When the value is greater than 0.0, causes the line to fade the further the segment is from the first particle segment. The alpha for a segment is calculated like this: segmentAlpha(s) = (1.0 - alphaFade) ^ s, where s is the segment index. The default value is 0.0.

eolFadeOutDuration : int

This property holds the end-of-life fade-out duration of the line. If set, each line remains in the place it was when the particle reached end of its lifetime, then fades out during this time period. The default value is 0.

length : real

This property holds the length of the line. If the value is set, the lines length is limited to the value. In this case the minimum delta of the line is the length divided by the segment count. If the value is not set, the line length varies based on the speed the particle moves as well as segment count and minimum delta. The default value is -1.0.

lengthDeltaMin : real

This property holds the minimum length between segment points. This parameter is ignored if the length parameter is set. The default value is 10.0.

lengthVariation : real

This property holds the length variation applied to each line. Variation is applied only if the length property is also set. The resulting line length clamps to positive values.

The default value is 0.0.

scaleMultiplier : real

This property holds the scale multiplier of the line. The scaleMultiplier value range is [0, 2]. The scaleMultiplier modifies the line size for the line segments. If the value is less than 1.0, the line gets smaller the further a segment is from the first segment and if the value is greater than 1.0 the line gets bigger. The size for a segment is calculated like this: size(s) = scaleMultiplier ^ s, where s is the segment index.

segmentCount : int

This property holds the number of segments in the line. The line is drawn using segment + 1 points, where the additional one comes from the particles current position. The default value is 1.

texcoordMode : TexcoordMode

This property holds the texture coordinate mode of the line.

texcoordMultiplier : real

This property holds the texture coordinate multiplier of the line. This value is factored to the texture coordinate values of the line. The default value is 1.0.