FALLOFF TEXTURE

The Falloff Texture is used to control the blend of two materials depending on the viewing angle of the material's geometry. Before Octane V3.08, this node was used to create fake fresnel. However, the use of this node is not necessary when Fresnel equations with 3.08 begin to give correct results. Octane now renders the fresnel effect as it should be during the material creation. Let's continue our explanations with this warning in mind.

衰减纹理

衰减纹理用于根据材质几何形状的视角来控制两种材质的混合。 在Octane V3.08之前，此节点用于创建假菲涅耳。 但是，当带有3.08的菲涅耳方程式开始给出正确的结果时，不必使用此节点。 现在，Octane将渲染菲涅耳效果，就像在材质创建过程中那样。 考虑到此警告，让我们继续进行解释。

HOW TO USE

Open the Node editor and prepare the setup as you see in the picture below. In this setup, 2 different materials are linked to "Mix material" and amount is controlled by falloff. As you can see in the picture, the whiteness towards the edges is actually a classic fresnel appearance. With the help of the Falloff mode value, this fake fresnel view will adapt itself according to the camera angle. In the below example "Normal vs. eye ray" is used as Falloff Mode. We will explain these options at the end of the page.

You can use the Falloff texture for other purposes. For example, it can be used to cover your objects with "dust", or it can be used on fabrics like velvet. We recommend you to use it mostly for Diffuse materials. Using the falloff node may not be accurate in case of Glossy and Specular materials because they produce realistic IOR and Fresnel.

如何使用

打开节点编辑器并准备设置，如下图所示。 在此设置中，将2种不同的材质链接到“混合材质”，并且数量由衰减控制。 从图片中可以看到，边缘的白度实际上是经典的菲涅耳外观。 借助“衰减”（Falloff）模式值，该假菲涅耳视图将根据相机角度进行调整。 在下面的示例中，“正常vs.眼睛光线”用作衰减模式。 我们将在页面末尾解释这些选项。

您可以将Falloff纹理用于其他目的。 例如，它可以用“灰尘”覆盖您的物体，也可以在天鹅绒等织物上使用。 我们建议您主要将其用于漫射材质。 在有光泽和高光材质的情况下，使用衰减节点可能并不准确，因为它们会产生逼真的IOR和菲涅耳。

falloff TEXTURE SETTINGS

衰减纹理设置

mode

There are 3 falloff modes here. Let's explain:

模式

这里有3种衰减模式。 让我们解释一下：

normal vs. eye ray

This is the default mode where the falloff is calculated from the angle between the surface normal and the eye ray. This mode is more commonly used for reflections and the falloff color range affects faces directly in front of the view and gradually falls at angled faces towards the sides as it falls away from the straight on viewing angle. Therefore the Falloff Direction parameter does not apply.

正常与眼睛射线

这是默认模式，其中根据表面法线和眼睛射线之间的角度计算衰减。 此模式更常用于反射，衰减颜色范围会影响直接位于视图前面的脸部，并且随着它从直线上的视角落下，它会逐渐以倾斜的角度朝侧面倾斜。 因此，“衰减方向”参数不适用。

normal vs. vector 90deg

The falloff is calculated from the angle between the surface normal and the specified direction vector maxing out at 90 degrees. This is similar to the default mode except that it maintains the effect of the color range according to the Falloff Direction x/y/z.

正常与矢量90度

根据表面法线与指定方向矢量之间的角度最大为90度的角度来计算衰减。 这与默认模式相似，不同之处在于它根据“衰减方向” x / y / z保持颜色范围的效果。

normal vs. vector 180deg

The falloff is calculated from the angle between the surface normal and the specified direction vector maxing out at 90 degrees. This is similar to the default mode except that it maintains the effect of the color range according to the Falloff Direction x/y/z.

正常与矢量180度

根据表面法线与指定方向矢量之间的角度最大为90度的角度来计算衰减。 这与默认模式相似，不同之处在于它根据“衰减方向” x / y / z保持颜色范围的效果。

mINIMUM aNd maxImum value

The relative amount of the Minimum and Maximum values that are at an angle to the straight on view. 0.1 will lead to almost complete coverage by the grazing value regardless of viewing angle, where as 1 will lead to almost complete coverage by the normal value.

最小值和最大值

与笔直视图成角度的最小值和最大值的相对量。 不管视角如何，0.1将导致掠射值几乎完全覆盖，而1则将导致正常值几乎完全覆盖。

falloff skew factor

This parameter is used to balance the influence of the normal and grazing angles. A low value means that the influence of the grazing angle is stronger - any textures controlled by the falloff Maximum value will cover more of the surface. Higher Skew Factor settings result in a stronger influence of the normal angle - any textures controlled by the Minimum value will cover more of the surface.

衰减偏斜因子

此参数用于平衡法线和掠角的影响。 较低的值表示掠射角度的影响更大-由衰减最大控制的任何纹理都将覆盖更多的表面。 较高的“歪斜因子”设置会导致法线角度的影响更大-“最小值”控制的任何纹理都将覆盖更多的表面。

falloff dIrectIon

The direction vector that is used by the Normal vs. Vector 90deg and Normal vs. Vector 180deg modes. For most materials, the fresnel effect (the default mode) is usually correct while falloff direction is used for exceptional cases which can be adjusted relative to the camera. Changing the rotation of the object will not change the orientation of the falloff direction.

衰减方向

法线与矢量90度模式和法线与矢量180度模式所使用的方向矢量。 对于大多数材质，菲涅耳效果（默认模式）通常是正确的，而在某些特殊情况下可以使用衰减方向，可以相对于相机进行调整。 更改对象的旋转不会更改衰减方向的方向。