MoonRay GUI Viewer V2

The moonray_gui_v2 executable is the successor to moonray_gui, which is the interactive counterpart to moonray. It leverages imgui as the graphical interface library in order to remove the more bloated QT dependency. It also includes a number of new features to make the tool easier to use.

The same core concepts are true for moonray_gui_v2 as they are for moonray_gui, so you can refer to the moonray_gui page for general information for now. This page will be dedicated to the differences coming with moonray_gui_v2, including 1) how to invoke it, 2) additions, and 3) hotkeys.

Usage

Here are some instructions on how to invoke moonray_gui_v2:

Prior to refplat-vfx2025
You can use the moonray_gui executable for v1, and the moonray_gui_v2 executable for v2.

refplat-vfx2025+
moonray_gui_v2 is the default from this point onward, because we do not support QT6. Using the moonray_gui executable will cause moonray_gui_v2 to run. The goal is to deprecate moonray_gui v1.

Additions for moonray_gui_v2

We’ve added a number of new features for moonray_gui_v2:

Status Bar

Instead of printing information about the status of the application to the terminal, we now display it in a bar at the bottom of the window. It includes information like:

  • Current pixel under the mouse
  • Channel mode
  • Fast progressive mode
  • Denoiser mode & buffers
  • Camera type (Orbit or Free)
  • Render output name

We also included a “?” button that opens a help menu. This help menu includes comprehensive information about the app and how to use it.

Image Navigation

The window is now re-sizable, instead of fixed-size, and we’ve added panning and zooming features. We also display the xyz axes to help users understand their scene’s camera orientation.

Inspectors

The pixel inspector allows users to investigate the RGB value of the pixel underneath their cursor. The scene inspector, which once printed results to the terminal, now has its own UI element and displays interactive updates.

Key Bindings

The key bindings menu allows you to view current hotkey bindings, and set custom bindings based on user preferences.

Snapshot Viewer

The snapshot viewer displays snapshots in your given snapshot directory path, and allows you to toggle between them for easy image comparison.

Hotkeys

Any keys that have changed between moonray_gui and moonray_gui_v2 have been marked with a star.

Camera Hotkeys

Action Hotkey Notes
Toggle Camera Type O  
Forward W  
Backward S  
Left A  
Right D  
Up SPACE  
Down C  
Slow Down Q  
Speed Up E  
Reset R  
Recenter F  
Frame Scene SHIFT+F new in v2
Print Matrices* M Previously T
Set Up Vector U  
Orbit* ALT+LMB FreeCam previously used LMB only
Dolly ALT+RMB  
Pan ALT+MMB  
Roll* CTRL+LMB Previously ALT+LMB+RMB

Denoising Hotkeys

Action Hotkey Notes
Toggle On/Off N  
Toggle Mode SHIFT+N  
Select Buffers B  

Channel Hotkeys

Action Hotkey Notes
RGB `  
Red 1  
Green 2  
Blue 3  
Alpha 4  
Luminance 5  
RGB Normalized* 6 Previously 7
Num Samples* 7 Previously 8

Color Management Hotkeys

Action Hotkey Notes
Exposure Increase UP  
Exposure Decrease DOWN  
Exposure Adjust X+LMB  
Exposure Reset SHIFT+X  
Gamma Adjust Y+LMB  
Gamma Reset SHIFT+Y  

Fast Progressive Mode Hotkeys

Action Hotkey Notes
Toggle On/Off L  
Next Mode ALT+UP  
Previous Mode ALT+DOWN  

Window Hotkeys

Action Hotkey Notes
Open/Close Key Bindings Editor G new in v2
Open/Close Pixel Inspector P new in v2
Open/Close Scene Inspector I now opens a window instead of printing info to console
Open/Close Snapshot Viewer ALT+K new in v2
Open/Close Status Bar ALT+S new in v2
Open/Close Exposure Editor* ALT+X Previously X
Open/Close Gamma Editor* ALT+Y Previously Y
Open/Close Path Visualizer V  
Open/Close Axis Display SHIFT+A new in v2

Path Visualizer

Action Hotkey Notes
Toggle On/Off SHIFT+V  
Pick pixel LMB just click the pixel you want to see the ray tree for
Previous Node SHIFT+LEFT selects the previous node (displays path vertex information in the path visualizer menu)
Next Node SHIFT+RIGHT selects the next node (displays path vertex information in the path visualizer menu)

Miscellaneous Hotkeys

Action Hotkey Notes
Render Output Previous ,  
Render Output Next .  
Save Image CTRL+S new in v2
Take Snapshot K  
Next Snapshot RIGHT new in v2, toggle next snapshot
Prev Snapshot LEFT new in v2, toggle prev snapshot
Tile Progress Toggle* T Previously P
Print Key Bindings H prints keybindings to console