VRay frame buffer

Search Keywords: VFB, G-buffer, frame buffer, render pass

General

In addition to rendering to the 3dsmax Rendered Frame Window (RFW or VFB), VRay allows you to render to a VRay specific frame buffer. The VRay frame buffer has some additional options to the 3dsmax VFB. The VRay VFB:

Allows you to view all render elements in a single window and switch between render elements very easily.

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

Allows you to perform simple color corrections on the rendered image.

Allows you to choose the order in which the buckets are rendered.

The VRay VFB also has some limitations, which are listed in the Notes section below.

Parameters

Enable built-in frame buffer - Enables the use of built-in VRay frame buffer. Due to technical reasons, the original 3dsmax frame buffer still exists and is being created. However, when this feature is turned on - VRay will not render any data to the 3dsmax frame buffer. In order to preserve memory consumption we recommend that you set the original 3dsmax resolution to a very low value (like 100x90) and turn off the 3dsmax Virtual Frame Buffer from the common 3dsmax render settings.

Get resolution from 3dsmax - this will cause the VRay VFB to take its resolution from the 3dsmax common render settings.

Output resolution - this is the resolution that you wish to use with the VRay frame buffer.

Render to memory frame buffer - this will create a VRay frame buffer and will use it to store color data that you can observe while rendering and afterwards. If you wish to render really high resolutions that would not fit into memory or that may eat up a lot of your RAM not allowing for the scene to render properly - you can turn this feature off and use only "render to VRay image file" feature.

Render to VRay image file - this feature writes directly to an external file that contains VRay raw data as it is being rendered. It does not store any data in the RAM, so this feature is very handy when rendering huge resolutions for preserving memory. In order to see what is being rendered - turn on the Generate preview setting.

Generate preview - this will create a small preview of what is being rendered. If you are using not the VRay memory frame buffer for conserving memory (i.e. Render to memory frame buffer is off) - you can use this feature to see a small image of what is being actually rendered and stop the rendered if there is anything that looks wrong.

Split render channels - this option allows you to save the channels from the VFB into separate files. Use the Browse... button to specify the file. This option is available only when rendering to a memory frame buffer. If rendering is done only to a raw image file, the render channels can be extracted from that file after rendering is complete.

Save RGB and Save Alpha - these options allow you to disable saving of the RGB and Alpha channels respectively. This can be useful if you only want to generate other render channels. Note that VRay will still generate those channels, however they will not be saved.

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. Yuo can also view the rendered image in monochromatic mode.

This will save the current frame data to a file.You can turn this on and of on-the-fly while rendering.

This will create a 3dsmax virtual frame buffer copy of the current VRay frame buffer.You can turn this on and of on-the-fly while rendering.

This will force VRay to render the closest bucket found to the mouse pointer. Drag the mouse over the VRay frame buffer while rendering to see which buckers are rendered first. You can turn this on and of on-the-fly while rendering.

This open permanently 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 - then you will see the info dialog only while yuor mouse button is down

This will open a so called "levels control" dialog which will let you define color corrections of various color channels. It will also show the histogram of the currently contained image data in the buffer. Click and drag your mid-button in the histogram to interactively scale the preview.

Clears the contents of the frame buffer. Somethimes helpful when startnig a new render to prevent confusion with the previous image.

VFB shortcuts

Here is the list of shortcuts you can use to navigate through the VFB image. Please note that VFB window must have the curent focus for the shortcuts to have effect:

Mouse Description

CTRL+LeftClick, CTRL+RightClick Zoom in/Zoom out

Roll the mouse-rollon button up/down Zoom in/Zoom out

Double-click LeftButton Zoom to 100%

RightClick 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

MidButton dragging view pan (hand tool)

Keyboard Description

+ / - Zoom in/Zoom out

* Zoom to 100%

Arrow keys Pan left, up, right, down

Notes

The VRay VFB does not display the G-Buffer layers (like Coverage etc.).

The VRay VFB does not work with stripe rendering.

Even though you select the VRay VFB as your output, the 3dsmax VFB is still created and thus takes additional memory. If you want to reduce that memory, you need to uncheck the Get resolution from MAX option, set the 3dsmax resolution to a low value like 100 x 100, and then select your real output resolution in the VRay VFB options.

If you have selected an output image file from the Common tab of the Render Scene dialog, VRay will fill out the 3dsmax RFW, and this will be saved as your image. If you want to save the VRay VFB instead, you should use the Split render channels option of the VRay VFB.