This page provides information on the V-Ray Frame Buffer.


Section Contents

 Page Contents



The V-Ray Frame Buffer (VFB) is a V-Ray specific frame buffer with additional capabilities including render history and lens effects.

The VFB has many advantages:

  • Allows the user to view all render elements in a single window and switch between them easily.

  • Keeps the image in full 32-bit floating-point format.

  • Allows you to view the rendered channels individually.

  • Has the ability to link to PDplayer.

  • Allows the user to make comparisons between two renders.

  • Provides the ability to save recent renders into history with comments.
  • Allows the user to add color correction and lens effects to renders without leaving SketchUp.


The V-Ray frame buffer with the color correction window docked.



 UI Paths:

||Open Asset Editor|| > Gear Icon > Output > VFB button


||V-Ray Toolbar|| > VFB button

Extensions > V-Ray > Show Frame Buffer



VFB Toolbar


This part of the toolbar sets the currently selected channel, as well as the preview mode. Choose which channels to see with the help of the buttons. You can also view the rendered image in monochromatic mode.
Saves the image into a single file. If a multi-channel type file is used (.exr, .vrimg) all the render elements will be saved in the same file.
Saves all the render elements into separate files

Saves all image channels to single file – Saves the image into a single file. If a multi-channel type file is used (.exr, .vrimg) all the render elements will be saved in the same file. (available from flyout)
Opens an image file to be previewed in the V-Ray Frame Buffer

Copies the current channel to the clipboard.
Clears the contents of the frame buffer. Sometimes helpful when starting a new render to prevent confusion with the previous image
Forces V-Ray to render the closest bucket found to the mouse pointer. Drag the mouse over the V-Ray frame buffer while rendering to see which buckets are rendered first. You can turn this on and off on-the-fly while rendering.
Allows you to render regions in the V-Ray VFB
Links the V-Ray VFB to Pdplayer
Swaps the A and B images
Enables or disables the comparison of images A and B from the VFB history. Click and hold down the left mouse button to change between horizontal and vertical comparison
Stops the current rendering
Repeat the last render
Opens the Color Corrections dialog which lets you define color corrections of various color channels. Right-click to dock or undock it.
Forces color clamping in the V-Ray VFB. Click and hold left mouse button to display the clamped colors in the V-Ray VFB
Permanently opens the info dialog which will give you information about the pixel you right-click the mouse pointer on. If you right-click the mouse pointer over a pixel without turning this setting on you will see the info dialog only while your mouse button is down.
Enables the White balance color correction
Enables the Hue/Saturation/Lightness color corrections
Enables the color balance color corrections
Enables the levels color corrections
Enables the curve color corrections
Enables the exposure corrections
Enables the usage of a background image
Displays the image in sRGB color space. Click and hold the left mouse button to switch between sRGB color space and ICC.
Enables and disables the effect of the Look Up table loaded in the Color Corrections settings. Hold down to chose between LUT and OCIO color corrections.
Shows the V-Ray VFB history window. Right-click to dock or undock it.
Enables visualization the pixel aspect ratio
Enables or disables stereoscopic preview. Click and hold down the left mouse button to pick between several stereoscopic modes
Opens the Lens Effects controls. Right-click to dock or undock them.

Opens the V-Ray Progress Window.


VFB History

The V-Ray VFB allows the user to keep a history of previously rendered images. The images are stored as .vrimg files on a location specified by the user. In addition to keeping history, this feature allows the user to set A and B image and compare them inside the VFB.



Enables the V-Ray VFB history
Saves the current image from the VFB to the render history
Loads the image selected in the Render history to the VFB
Removes the selected image from the render history
Sets the currently selected image as image A for A/B comparison in the VFB
Sets the currently selected image as image B for A/B comparison in the VFB

image2014-1-24 1-53-50.png

Swaps the A and B images.

image2014-1-24 1-53-22.png

Enables or disables the image comparison. Click and hold the button to switch between horizontal and vertical comparison.
Opens out the VFB history options which allow the user to specify the location where the history will be saved and the amount of disk space available. It also allows you to turn on auto-saving of each rendered image to the history.


The keyboard keys from 1 to 9 can be used to quickly switch between the first 9 images from the history.

Right-clicking on an image in the VFB history brings up a pop-up menu with some useful options:


Edit comment – Specifies a text comment to the image; the comment appears in the "Details" column.

Set A – Sets the image as the "A" image when comparing two images.

Set B – Set the image as the "B" image when comparing two images.

Load – Loads the selected image in the VFB (same as double-clicking on the history image).

Delete – Deletes the selected image from the history. The image is moved to the system's Recycle Bin and can be restored from there if needed.

Load Color Corrections – Loads the VFB color correction controls from the selected image.

Reload History – Re-reads the history image list. This may be needed if the history folder is updated outside of SketchUp (e.g. from another SketchUp session).


The Load V-Ray Settings and Compare V-Ray Settings options are not available in V-Ray for SketchUp.

VFB Render History

History Directory – Specifies the location where images will be stored.

Maximum Size on Disk (MB) – Specifies the maximum amount of space used on the Hard disk.

Use Project Path – When enabled, the VFB will use the project path as the History Directory. If a project has been created but not saved yet, the default SketchUp temp folder will be used (The path is set in Preferences > Files > Models). If the user saves the project or opens an existing project, the project path will be the same as the project file location.

Auto Save – All renders will be automatically saved (If only completed renders are required, then Completed Renders Only should be checked).

Auto Load Color Corrections – When enabled, any color corrections used on an image will also be loaded.

Completed Renders Only – When enabled, only completed renders will be saved to the VFB history.


Lens Effects




The V-Ray Lens Effects dialog can be accessed through the Open lens effects settings button at the bottom of the VFB Toolbar. See the Lens Effects page for additional information.

V-Ray comes with a Lens Effects Filter Generator, a standalone tool that works with the Lens Effects dialog.


Frame Stamp

The frame stamp is a convenient way to put some short text over the rendered images. It can be useful in many ways - for example, in network rendering, to quickly determine which frames were rendered by which machine. The frame stamp is one line of text, which appears at the bottom of the image.




Edit box – Specifies the text you wish to appear in the images. You can also use some special keywords, all of which begin with the percent symbol (%).

Apply Stamp – Turns the frame stamp on and off.

Insert Keyword – Opens the Stamp Variables Window, which allows the user to select keywords to add to the stamp. The keywords are replaced by V-Ray with the corresponding value:

%vraycoreThe current version of the V-Ray core
%rendertimeThe render time for the current frame

Align Left – When enabled, the frame stamp will be aligned to the left.

Align Bottom – When enabled, the frame stamp will be placed at the bottom of the image.

Choose Font – This button allows you to choose a font and font attributes for the text in the frame stamp.


VFB Progress Bar

The nested progress bar gives real-time updates about the status of the render process. The full progress log can still be accessed in the V-Ray Progress window, which is opened through the small square button at the bottom-right corner of the VFB.



VFB Shortcuts

Here is the list of shortcuts for navigating through the VFB image. Please note that VFB window must have the current focus for the shortcuts to have effect:


CTRL+Left-click, CTRL+Right-clickZoom in/Zoom out
Mouse wheelZoom in/Zoom out
Double-click Left ButtonZoom to 100%

Show the info dialog with the properties of the last pixel clicked. In order to see the info non-stop - turn on the info dialog button 

Middle Button draggingView pan (hand tool)
Shift+Left-click+Drag (In Interactive mode only)Orbits the camera view.
CTRL+Left-click+Drag (In Interactive mode only)Pans the camera view.
Shift + Mouse wheel scroll (In Interactive mode only)Zooms in/out the camera view.
+ / -Zoom in/Zoom out
*Zoom to 100%
Arrow keysPan left, up, right, down



  • The OpenEXR file format is an open file format for high dynamic range images originally developed by Industrial Light and Magic. The official site of the OpenEXR file format is