--- title: "V-Ray Falloff" canonical: "https://documentation.chaos.com/space/VRAYHOUDINI/113280062/V-Ray%20Falloff" format: markdown --- This page provides information on the V-Ray Falloff texture. Overview V-Ray Falloff produces a gradient texture based on the angular falloff of the surface of the geometry to which the texture is applied. The resulting map can simulate the falloff of opacity, reflection, and refraction for surfaces where these properties vary depending on the surface's angle to the camera, such as curved glass or water. To create the texture, V-Ray Falloff starts with two colors, usually black and white. Placement of these colors on the surface is based on the Falloff Type and Direction Type selected. The remainder of the map is generated as a gradient between these two colors, with a gradual falloff between the colors. Settings Type  – Specifies the type of falloff: Towards/Away  – Based on face normal directions. Faces with normals that point in the  Direction Type  generate  Color 1  while those facing in the opposite direction (180 degrees off the falloff direction) generate  Color 2 .  Perpendicular/Parallel  – Based on face normal directions. Faces with normals that point in the  Direction Type  generate the  Color 1  while those facing in a perpendicular direction (90 degrees off the falloff direction) generate the  Color 2 . Fresnel  – Based on changes to the index of refraction (IOR) over the surface due to Fresnel calculations. Faces with normals that point in the  Direction Type  generate the  Color   1  and those facing in other directions generate varying colors depending on the IOR set by  Fresnel Ior .  Distance Blend  – Sets the falloff range based on distance from the camera, as specified by  Distance Near  and  Distance   Far . This option is useful for generating a Z-depth type of map when rendering a very large object such as terrain, where the Falloff Map can be used as a mask to dim distant details.  For more information, see the  Distance Falloff Type example  below. Color 1/2  – Sets the extreme ends of the range of colors for the Falloff Map's gradient. The specific placement of these colors on the surface is determined by Type  and Direction Type . Direction Type  – Specifies the falloff direction to be used by the Falloff Type. Distance Extrapolate – Enables extrapolate for the distance blend falloff type. Distance Near – Specifies near distance for the distance blend falloff type. Distance Far – Specifies far distance for the distance blend falloff type. Fresnel IOR – Specifies IOR for the Fresnel falloff type. Use Blend Input  – Enables the  Blend Input  parameter for controlling the blending. Blend Input  – Specifies the final blending amount that is taken from the texture. Use Blend Curve  – Enables the Blend Curve for controlling the blending. Falloff Curve  –  Specifies the falloff direction to be used by the Direction Type : View Z/View X/View Y  – Uses the camera viewing direction. This is the most common selection. Explicit  – Uses the direction specified by the  Explicit Direction  parameter. Local X /  Local Y  /  Local Z  – Uses one of the object's local axes. World X  /  World Y /  World Z – Uses one of the world axes. Color Tweaks Default Color  – Specifies the color when there are no valid UVW coordinates. Mult  – Specifies a strength multiplier for the texture color. Offset  – Color corrects the texture by adding the RGB color values specified here to the RGB color values in the texture. Invert – When enabled, inverts the resulting texture color. Alpha Tweaks Source  – Specifies where the alpha channel is drawn from: Alpha  – Alpha channel is drawn from the texture. Color  – Alpha is generated from pixel intensity. Opaque  – Alpha channel is fully opaque. Use  – Differentiates between textures exported from different applications. You can choose between  Color Intensity (3ds Max)  and  Color Luminance (Maya) . Mult  – Specifies a multiplier for the texture alpha. Offset  – Specifies an additional offset for the texture alpha. Invert  – When enabled and  Invert  from  Color Tweaks  is also on, the resulting texture alpha is inverted as well. Example: Distance Falloff Type In the example below, the Type has been set to Distance Blend and mapped to the diffuse color of the V-Ray Material on the humbucker pickups on the guitar.   Distance Near : 0, Distance Far : 27 Distance Near : 15, Distance Far : 27   Distance Near : 20, Distance Far : 27 Example: Falloff Colors This example shows how Color 1 and 2  control the range of colors for the V-Ray Falloff's gradient when the texture is mapped to the V-Ray Material  Diffuse  slot. Color 1 is the main color for the object, while Color 2 gives it a tint. The distribution of Color 1 and 2 can be controlled by the Falloff Type and Falloff Direction Type parameters. Here, we've set red as  Color 1  and yellow as Color 2 . The Falloff Direction Type  is View Z . By changing the Falloff  Type , we control the gradient spread. Type = Towards/Away Type = Perpendicular/Parallel Type = Fresnel Type = Distribution Blend ( Distance Far = 5.8) Example: Falloff Type This example shows how the different Falloff types affect the object's reflection. Here, we have a V-Ray Falloff texture mapped to the Reflection color of a V-Ray Material. The Falloff Direction Type  is set to View Z . Red and yellow are set as Color 1 and Color 2 . Type = Towards/Away Type = Perpendicular/Parallel Type = Fresnel Type = Distribution Blend Example: IOR This example shows how the Fresnel IOR values affect the renderer. Here, the V-Ray Fresnel texture is mapped to the Reflection color of a V-Ray Material. Color 1 and 2 are set to red and yellow respectively. The Falloff Type is set to Fresnel , and the Falloff Distance Type is set to View Z . Fresnel IOR = 1 Fresnel IOR = 1.5 Fresnel IOR = 2 Fresnel IOR = 2.5 Fresnel IOR = 3