# 场景属性¶

Tip

## 单位¶

Tip

Tip

mil

0.0000254

", in

0.0254

', ft

0.3048

yd

0.9144

ch

20.1168

fur

201.168

mi, m

1609.344

um

0.000001

mm

0.001

cm

0.01

dm

0.1

meter

m

1.0

dam

10.0

hm

100.0

km

1000.0

## 音频¶

### 间距模型¶

Changes how the sound attenuation is calculated based on the distance. Most physically correct is the Inverse model, but it's also possible to choose a linear and an exponential falloff. The clamped modes limit the volume to be lower than 100% (1.0), that means if the distance is smaller than the reference distance, the volume is always 100%. For an exact description of each option see the OpenAL documentation.

Speed of the sound for the Doppler effect calculations. The typical value is 343.3 m/s in air, in water for example this value is around 1560 m/s.

Controls how strong the Doppler effect is. You can exaggerate or attenuate the change of pitch, but physically correct is a factor of 1.0.

Rate