The Gradient Editor lets you control Gradient textures in modo. Gradients are useful in modifying values gradually across a certain parameter such as length or angle. Once you have added a Gradient texture in the Shader Tree and indicated the effect it will have on the material, you will need to select the input parameter on the 'Gradient Texture' properties panel, this defines how the gradient modulates the surface is is affecting. By clicking the 'Edit Gradient' check box one can open the Gradient Editor window. The 'Gradient Editor' is in many ways similar to the graph editor, the difference being the graph editor modifies values over time.
Channels
From within the channel section, users can select the value they wish to modulate. For diffuse color this would be the 'Color R,G and B channels, for specular amount, this would be the 'Value' channel. Once selected, a line representing the value appears in the graphing window.
Key Creation
Keys can be added to the currently selected curve(s) by MMB clicking either on the curve itself or anywhere on the background.
Setting Colors for Keys
The color of selected keys can be set or adjusted by either clicking and dragging on a Color Picker viewport or from the RMB context menu. Selecting 'Key Color' from this menu will open the Color Picker from which a color may be chosen. In both cases additional keys may be created on associated curves at the key Input value.
Deleting Keys
Keys can be deleted from curves in two ways:
To delete only the currently selected keys press the 'Delete' key.
To delete the currently selected keys and keys at the same Input value on associated curves select 'Delete Key' from the RMB context menu.
Selection
LMB+click will select any key under the cursor, holding the 'Shift' key while selecting adds to the selection, and holding the 'Ctrl' key removes a key from the selection set. Clicking on the background deselects all keys.
LMB+click drag on the background starts box marquis selection, drag out a box to enclose the keys you want to select and release the mouse button. All keys within the box will become selected, any outside the box will be deselected. Holding down the 'Shift' key adds the keys within the box to the selection while the 'Ctrl' key removes them.
LMB+click on a curve in the background (dimmed) will select the curve. Curves can be added to the selection by holding down the 'Shift' key and clicking on a curve and can be removed from the selection by holding down the 'Ctrl' key.
Curves may also be selected from the menu at the top left of the viewport, this menu lists all the curves associated with the currently selected Gradient item(s).
Editing
LMB+click drag on a key selects the key if it's not already selected and allows quick editing of both Input & Output values at the same time. If there are several keys already selected and you click drag on one of them then all the selected keys will be modified.
MMB & Drag on a key works in a similar way except that editing is constrained to the Output value. Similarly RMB & Drag constrains the edits just to the Input Parameter value.
MMB+click drag vertically on the background adjusts the Output value of all selected keys.
RMB+click drag horizontally on the background adjusts the Input value of all selected keys.
'Ctrl'+MMB+click drag on the background provides constrained editing of Input & Output values for selected keys based on the initial direction of movement.
LMB+double click on a key selects all the keys on the curve.
Context Menu
The Gradient Editor context menu is accessed by RMB click & release. If the cursor is over an un-selected key when the menu is opened the key will be added to the selection. Operations performed from the context menu will affect all the currently selected keys.
Navigation
Panning & Zooming behavior in the Gradient Editor is similar to the 3D viewports with a few additions:
Alt-MMB Drag adjusts the start value of the Input (horizontal) range displayed in the editor, while Alt-RMB Drag adjusts the end value of the Input Range.
Alt-Shift-MMB zooms the Output Range displayed in the editor, while Alt-Shift-RMB zooms the Input Range. In both cases the zoom is centered on the initial cursor location.
Alt-Control-RMB provides box zooming.
Mouse Wheel - Zooms in and out around the cursor location.
O - Hover mouse pointer over color picker to open Color Options Dialog.
