--- title: "VRaySamplerInfo" canonical: "https://documentation.chaos.com/space/VMAX/113587182/VRaySamplerInfo" format: markdown --- This page gives information about the Sampler Info Render Element. Overview The Sampler Info Render Element is a color image that provides information about the scene, with the choice to show any of various aspects as color blocks. This render element p rovides information about various aspects of the shaded points such as position, normal, bump normal, reflection/refraction vectors and UVW coordinates. This render element can be used either for world position passes or normal passes. It extracts particular information about the scene, converting the gathered information into RGB data for use in compositing. ||Render Setup window|| > Render Elements tab > Add button > VRaySamplerInfo   Parameters This render element is enabled through the Render Elements tab of the Render Setup window in 3ds Max and displays its parameters in a rollout at the bottom of the window: VRayVFB  – Enables the render element inside the V-Ray Frame Buffer. Deep output  – Specifies whether to include this render element in deep images. Type  –   Controls the type of render element produced by VRaySamplerInfo: Point  –   The X, Y, and Z coordinates of the point are converted to RGB data according to the  Coord system  that is set. This outputs a Position Pass for use in compositing. Normal vector  – The direction of the normal at the particular shaded point according to which  Coord system  is set. Reflection vector  –   Commonly used for adjusting reflections in the composite. Refraction vector  – Commonly used for adjusting refractions in the composite. UVW coordinates  – Extracts the UVW coordinates of the object at the particular shaded point.  This can be used to apply another texture at a composite level. Normal vector with bump mapping  –   Produces the bump normal according to the  Coord system  that is set. Backward occlusion  –   The red and green components of this render element represent the screen position of the shaded point at the beginning of the motion-blurred frame, while the blue component represents camera occlusion at the beginning of the motion-blurred frame. Together with the  Forward occlusion  render element, this can be used for denoising and/or post-process motion blur. Forward occlusion  –   The red and green components of this render element represent the screen position of the shaded point at the end of the motion-blurred frame, while the blue component represents camera occlusion at the end of the motion-blurred frame. Together with the  Backward occlusion  render element, this can be used for denoising and/or post-process motion blur. Integer ID from node user attribute  –   Extracts any integer node user property into an integer render element. Can be used as an extended Object ID. Float number from node user attribute  – Extracts any floating-point node user property into a single-channel floating-point render element. Can be used to extract additional masks. Tangent vector in object space  –  Displays tangent vector according to the  Object space . Bitangent vector in object space  – Displays bitangent vector according to the  Object space . Point multiplier  –   Acts as a multiplier when  Type  is set to  Point . Refract IOR  –   Sets the index of refraction when  Refraction vector  is set as the  Type . UVW channel  – The UVW mapping channel used when the  Type  is set to  UVW coordinates. UVW mode  –   Specifies what happens to UVW values outside the 0.0-1.0 range of the unit texture square: Normal  –   Stores the UVW coordinates without modification. Clamp  –   UVW coordinates above 1.0 are clamped to 1.0, and values below 0.0 are clamped to 0.0. Tile  –   Wraps the UVW coordinates to the unit texture square.    Coord system  – Controls the coordinate system used: World  – X, Y, and Z coordinates (in world space) of the point are converted to RGB data. Object  –   X, Y, and Z coordinates (in object space) of the point are converted to RGB data. Camera  –   X, Y, and Z coordinates (in camera space) of the point are converted to RGB data. Relative  –   X, Y, and Z coordinates in the object space of the  Relative node  are converted to RGB data. Relative node  –   When  Coord system  is set to  Relative , this specifies the scene node relative to which the point/vector data is stored. Output  –   Controls the way data is stored in the render element when the type is a normal vector, or a reflection/refraction direction: Vector (signed)  –   Values are stored directly without modification, including negative components. Color (unsigned)  –   Values are scaled down by 0.5 and offset by 0.5 so that (0, 0, 0) maps to (0.5, 0.5, 0.5), (-1, -1, -1) maps to (0, 0, 0) and (1,1,1) maps to (1,1,1). This avoids negative values which might be necessary for some compositing packages. User attribute  –   Determines which user attribute to connect to when  Integer ID from node user attribute  or  Float number from node user attribute  are selected as  Тype . Occlusion bias  –   Controls the positional bias of the  Backward occlusion  &  Forward occlusion  types in order to prevent incorrect self-occlusion. Common Uses The VRaySamplerInfoTex texture extracts particular information about the scene. It then converts the gathered information into RGB data that can be used for compositing. Here are examples of the types of data that can be extracted, and how that data is displayed in the render element. The following examples have the coordinates system set to world space. Point Type in world space Normal vector in world space Reflection vector Type in world space Refraction vector Type in world space The following examples have the coordinate system set to object space. Point Type in object space Reflection vector Type in object space Refraction vector Type in object space The following examples have the coordinates system set to camera space. Point Type in camera space Reflection vector in camera space Refraction vector in camera space The following examples have the coordinates system set to relative space. Point Type in relative space Reflection vector Type in relative space Refraction vector Type in relative space   Example: Re-texturing in composite Using the VRaySamplerInfo Render Element makes it possible to apply a new texture to an already rendered still or sequence via setting its Type to UVW coordinates. This then enables the creation of what effectively amounts to a new Diffuse Filter Render Element which can then be used in a composite, enabling a change of texture to be easily made. It is worth noting that any UV stretching on the model carries through into the UVW pass created by the VRaySamplerInfo. See the render before and after compositing. Before After   Supported UVW Coordinate Types The table below provides some details on the supported UVW coordinate types within the Sampler Info Render Element. Pass types such as Normal , Normal vector with bump mapping , World coordinates and Point can be used to relight a scene at a composite level. While UVW coordinates and Object coordinates can be used to re-texture items in a scene in composite. The  Reflection vector type can be used to adjust or remap reflections, similarly the  Refraction vector can do the same at a composite level for refractions. Some types such as the Forward occlusion and  Backwards occlusion can be used together for denoising and/or post-process motion blur.   The  Integer ID from node user attribute can be used as an extended Object ID and the  Float number from node user attribute can used to extract additional masks.   Pass Type Coord. System UVW Mode Output V-Ray Render V-Ray GPU Point World Point Object Point Camera Point Relative Normal World Vector (signed) or Color (unsigned) PARTIAL Normal Object Vector (signed) or Color (unsigned) Normal Camera Vector (signed) or Color (unsigned) PARTIAL Normal Relative Vector (signed) or Color (unsigned) PARTIAL Reflection World Vector (signed) or Color (unsigned) Reflection Object Vector (signed) or Color (unsigned) Reflection Camera Vector (signed) or Color (unsigned) Reflection Relative Vector (signed) or Color (unsigned) Refraction World Vector (signed) or Color (unsigned) Refraction Object Vector (signed) or Color (unsigned) Refraction Camera Vector (signed) or Color (unsigned) Refraction Relative Vector (signed) or Color (unsigned) UVW coordinates Normal UVW coordinates Clamp UVW coordinates Tile Normal vector with bump mapping World Vector (signed) or Color (unsigned) Normal vector with bump mapping Object Vector (signed) or Color (unsigned) Normal vector with bump mapping Camera Vector (signed) or Color (unsigned) Normal vector with bump mapping Relative Vector (signed) or Color (unsigned) Backwards occlusion Forward occlusion Integer ID from node user attribute Float number from node user attribute