This page provides information on V-Ray Proxy Mesh objects.
Overview
V-Ray Proxy Mesh allows geometry to be imported from an external mesh at render time only. The geometry is not present in the SketchUp scene and does not take any resources. This allows the rendering of scenes with many millions of triangles - more than SketchUp itself can handle.
UI Paths
||V-Ray Asset Editor|| > Geometries (right-click) > Proxy Mesh
||V-Ray Asset Editor|| > Create Asset (left -click) > Geometries > Proxy Mesh
||V-Ray Objects Toolbar|| > Export Proxy
||V-Ray Objects Toolbar|| > Import Proxy or V-Ray Scene
Sketchup Menus Ribbon
||Extensions|| > V-Ray > Objects > Export Proxy
||Extensions|| > V-Ray > Objects > Import Proxy or V-ray Scene
Exporting a Mesh to a File
You can export a mesh through the V-Ray Object Toolbar, or through the Extensions menu.
To create a proxy through the V-Ray Object Toolbar, select the group or component you want to export. The icon will remain inactive until an object in the scene is selected. When you select a group or component in the scene, the Export Proxy button will become active.
Click on it to open the Export Proxy window.
Mode – Allows you to choose between Proxy Mesh (.vrmesh) and Proxy Scene (.vrscene) export. The addition of Proxy Scenes allows you to export a selection of geometry, lights, and special objects combined into a single proxy.
File Path – The name of the file. The file is saved in a custom folder, specified by pressing the Save File icon on the right.
File Path – The name of the file. The file will be saved in a custom folder, specified by pressing the Save File icon on the right.
Preview type – Chooses the method for generating the proxy preview:
Face Skipping (very fast) – The fastest preview method.
Refined Clustering (quality) – Slightly slower, but generates a more precise preview mesh.
Vertex Clustering (fast) – This method is fast and generates a fairly precise preview mesh.
Faces in Preview – Specifies the number of faces in the viewport preview of the proxy.
Overwrite Existing File – When enabled, V-Ray will automatically overwrite any existing vrmesh files.
Replace Object with Proxy – Enables the original meshes to automatically replace their proxy versions.
Export – Exports the .vrmesh file to the specified folder.
Importing a V-Ray Proxy
To import a V-Ray mesh, click the Import V-Ray Proxy button and choose a .vrmesh file from your computer. Once loaded into the scene you will need to re-apply materials through the material editor.
The Import V-Ray Proxy button also gives you the option to load a .vrscene file and .abc file.
Parameters
File – Specifies the proxy file.
Preview Type – Specifies the viewport preview mode. This does not affect the final render.
Proxy Preview – Portions of the mesh will be previewed in the viewport with some faces hidden.
Whole Mesh – The entire mesh will be previewed in the viewport.
Bounding Box – Previews are shown as bounding boxes.
Point (Origin) – Previews the mesh as a bounding box outline with its own point of origin and axes indicators.
Custom Preview – This option allows for changing the proxy file without affecting/updating the preview geometry.
Be aware that depending on the V-Ray proxy object detail, using the preview type Whole Mesh can put substantial load on your system.
Scale Factor – Scales the imported proxy object. Useful to adjust the asset's scale according to the scene units.
Note that the original size of Chaos Cosmos assets is measured in centimeters. On import they are appropriately scaled according to the specifics of SketchUp which operates in inches (regardless of SketchUp's display units). Therefore, when Cosmos assets are merged the resulting Proxy Mesh uses a Scale Factor of ~0.39. It is best to leave this value unmodified unless a custom unit conversion is desired.
Use Mtl Override – When enabled, the global Material Override option in the Render Settings overrides the .vrscene proxy assets. When disabled, the materials in the referenced scene are not affected by the Material Override option in the Render Settings.
Materials
Materials – When enabled, ignores any material assignment to the proxy object and instead forces the proxy to be rendered using the colors or materials specified in this list.
Face IDs are under-the-hood object parameters that mark the designation of different materials applied to a single object. If a texture is present in multiple materials applied to the same object, this mode will randomize them for each material.
A common use case is Proxy Mesh assets with multiple available materials slots but only one material applied to all of them.
Animation
Enabled (
) – Turns the Animation on and off.
Offset – Offsets the beginning of the animation by the given number of frames. You can use positive as well as negative values here. The default value of 0.0 starts the animation at the first available frame.
Playback type – Determines how playback will behave.
Loop – The animation plays to the end and loops back to the first frame once it has finished.
Once – The animation plays once.
Ping-pong – The animation is looped by playing it backwards once the last frame has been reached and then playing it forward again when the first frame is reached again.
Playback Speed – A multiplier for the speed of the animation. A value of 1.0 plays the animation at normal speed, while 2.0 plays it at double speed and 0.5 plays it at half speed. Putting negative numbers here will make the animation play backwards. This option may not work very well for sequences of .vrmesh files.
The .vrmesh File Format
Meshes are exported to a special .vrmesh file format. It contains all geometric information for a mesh - vertices and face topology as well as texture channels, face material IDs, smoothing groups, normals - in short, everything that is needed to render the mesh. In addition, the mesh is pre-processed and subdivided into chunks for easier access. The file also contains a simplified version of the mesh used for preview purposes in the viewports.
It is important to realize that the mesh is in a "ready to render" format. No further modifications to the mesh are expected. Modifiers cannot be applied to the mesh, and it cannot be animated it in any way except for the proxy object's position/orientation.
Notes
Populating a scene with multiple instances of the same Proxy Mesh is best done by utilizing SketchUp's native component functionality. Instancing a Proxy Mesh component (instead of importing it multiple times) saves memory since the .vrmesh file will be loaded only.
The resulting .vrmesh files can be rendered outside of SketchUp - for example, by V-Ray for 3ds Max, V-Ray for Maya or in the standalone version of V-Ray.
- Proxy UV mapping cannot be modified and it is not affected by SketchUp's material size. Adjustments are possible only through the V-Ray texture placement settings.
- Displacement of Proxy object is not supported.
- A Proxy Mesh may take a few seconds to generate its material slots if the loaded file has numerous face IDs.
- Memory usage can be viewed from the Stats section of the new V-Ray Frame Buffer.
- The Hide Widget hides a Proxy Mesh from the viewport only when set to Bounding Box and Point (Origin) preview type.
- Scene units in SketchUp are always calculated in inches.
- Proxy Mesh re-export does not export the Proxy Mesh. It only exports a Proxy Preview with a simple mesh. To export the Proxy Mesh, export it as an asset with its .vrmat materials from the V-Ray Asset Editor>Save Assets To File.