When you right-click an ActiveShade window, the lower-left quadrant of the quad menu displays a set of commands for ActiveShade.

These are general-purpose commands.
Show Last Rendering—Displays the last rendering in a virtual frame buffer. Not available if no rendering has been made during this session.
Render—Displays the Render Scene dialog. When you use the ActiveShade quad menu, initially Render Scene is set to render the ActiveShade window.
Render Last—Repeats the last render, using the last viewport from which you rendered.
Material/Map Browser—Displays a modeless Material/Map Browser.
Material Editor—Displays the Material Editor.
These are the commands that perform ActiveShade operations.
Draw Region—When on, lets you draw a rectangular region of the ActiveShade window. While it is active, only the region is updated by interactive reshading. This can save time, and also help you concentrate on just a portion of the image to be rendered. Default=off.
To turn off Draw Region, click outside the rectangular region. The entire ActiveShade window is updatable again.
Initialize—Initializes the ActiveShade window. To keep the ActiveShade window current, you need to choose Initialize after transforming, modifying, or otherwise changing geometry. If you have turned off Automatic Reinitialization, you also need to choose Initialize after you update a mapped material.
Update—Updates the ActiveShade window. To keep the ActiveShade window current, you need to choose Update Shading if you have previously turned off Automatic Shading Update.
Select Object—(Viewports only.) When on, you can select an object in the ActiveShade window by clicking. You can select only one object at a time.
When an objects is selected in the ActiveShade window, the Initialize pass resamples textures for that object alone. This improves the window's rendering speed, and is useful when you are adjusting texture display.
Toggle Toolbar—(Viewports only.) Toggles display of the ActiveShade window toolbar in viewports.
Keyboard shortcut: SPACEBAR
The Keyboard Shortcut Override Toggle must be on for the spacebar to toggle the ActiveShade toolbar.
These commands control how the ActiveShade window behaves.
Act Only On Mouse Up—When on, changes you make to light and material parameters (for example, the RGB or Multiplier spinners) update the ActiveShade window only after you release the mouse. When off, changes to these parameters are updated immediately, as you drag the mouse. Default=on.
Turning off Act Only On Mouse Up can make the ActiveShade window more responsive to changes, but it can also slow performance.
Auto Initialization—When on, changes you make to textures (mapped materials) automatically cause the ActiveShade window to initialize. Default=on.
Initialization can be time consuming in complex scenes. To save time, you can turn off Automatic Reinitialization, or use Draw Region to restrict initialization and shading updates to only a portion of the scene.
Auto Update—When on, changes you make to lighting, and materials without maps, automatically cause an update of the ActiveReshade window. Default=on.
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