The Viewport tab is the largest (By default) tab in the user interface. It is the primary tab in which items are placed and positioned and the user navigates around the scene within this tab.
The viewport tab is by default the preview of the output for the render although this can be changed to a specific camera in the Render Settings.
Located in the top right corner of this tab are it’s main controls.
The left most icon is the Auto Exposure tool which automatically sets the tone mapping settings for the scene to provide a suitably lit render.
The next icon opens up the Draw mode dropdown menu.
This menu shows all available draw styles for the viewport, including NVIDIA Iray preview mode, which shows a low resolution preview of the output render using the current render settings.
The next dropdown is the View Selection menu, which enables the user to quickly change between cameras or default views such as orthographic or default views. This menu also allows the viewing of the current UV map for the selected item.
The next icon opens the viewport burger menu.
This menu allows the used to toggle various features of the viewport, such as Aspect frame, rule of thirds guide etc.
The coloured cube allows the user to rotate the camera around it’s focal point, or quickly change to a specific position by clicking on the edges or faces of the cube. This merely rotates the camera and does not switch to a flat view.
The small white icons on the right from top to bottom are as follows:
Rotate: Rotates the camera around its current focal point
Pan: Pans the camera
Zoom: Zooms in and out
Focal Point: Sets the camera focal point to the base of the selected object
Reset: Sets the current view back to the default settings. NOTE: If you are currently viewing the scene through a camera, this will reset the camera back to its default position.