The Transparency tab of the View Configurations dialog.
This tab of the View Configurations dialog allows the designer to set the transparency of each object type individually, and on a per layer basis, for each layer that can be used in board design.
Although the transparency settings can be defined for any 2D view configuration, Altium Designer features a dedicated default 2D view configuration for this very purpose – Altium Transparent 2D. It is identical in all other aspects to the Altium Standard 2D view configuration. It differs only by its Transparency tab, with example transparencies defined ready. By configuring transparency settings in this dedicated view configuration, you then have the ability to quickly switch between transparent (Altium Transparent 2D) and standard (Altium Standard 2D) views for your board, essentially turning transparency ON or OFF. This view configuration (Altium Transparent 2D.config_2dsimple) can be found alongside all other default view configurations installed with Altium Designer, in the \Users\<ProfileName>\AppData\Roaming\Altium\Altium Designer <GUID>\ViewConfigurations folder of your installation.
This is one of four tabs available for a 2D view configuration – accessed from within the View Configurations dialog. This dialog can be accessed from both the PCB Editor and the PCB Library Editor, in the following ways:
In 2D Layout Mode, choose the Design » Board Layers & Colors command (PCB Editor), or choose the Tools » Layers & Colors command (PCB Library Editor).
Press the L key.
To access 2D view-related tabs, either ensure the workspace is in 2D Layout Mode prior to accessing the dialog, or select a 2D configuration in the Select PCB View Configuration region, once the dialog is accessed.
The Transparency tab can also be accessed directly, by choosing the Options » Board Layers Transparency command from the workspace's right-click context menu.
Transparency for selected objects/layers - use the controls associated to this field to set the transparency for the currently selected cell(s) in the grid. Move the slider bar to the right to increase transparency. If using the spin control, you can simply type the required percentage transparency directly into the field.
Transparency is set on a percentage scale, in 1% increments. 0% is fully visible (solid), all the way up to 100%, which is fully transparent (or invisible).
Only show used layers - this option controls the layers that are displayed within the Transprency Grid. When enabled, only layers in the current board's layer stack will be presented. To show all layers supported for board design in Altium Designer (used and unused), disable this option.
When wanting to setup a global configuration for transparencies – that can be used for any board design – it can be a good idea to disable the Only show used layers option, then configure transparency settings for each and every layer. In this way, if additional layers are added to a particular board design, the transparency settings will already be defined, and ready for use from the outset.
This, the main area of the tab, presents a grid with rows representative of each layer, and columns representative of each design object type. Each cell of the grid (a layer-object intersect) displays the current transparency level for that object, on that layer. Not only does the grid facilitate a unique transparency setting to be defined for a particular object across different layers, it also allows different objects to have different transparencies on a specific layer. The layers themselves are grouped by their functional types:
Signal Layers – Top Layer, Bottom Layer, Mid-Layer 1-30
Internal Planes – Internal Plane 1-16
Other Layers – Multi-Layer, Drill Guide, Keep-Out Layer, Drill Drawing
Silkscreen Layers – Top Overlay, Bottom Overlay
Mask Layers – Top Paste, Top Solder, Bottom Solder, Bottom Paste
Mechanical Layers – Mechanical 1-32. The following system layers are also included in this grouping: Connections, DRC Error Markers, DRC Detail Markers, Selections, Visible Grid 1, Visible Grid 2, Top Pad Master, and Bottom Pad Master.
If the Only show used layers option is disabled, layers that are currently not used in the design have their names and transparency values displayed in gray text. You can still configure the transparencies as required for these unused layers.
Use the following multi-select controls to select multiple objects, then set a common transparency for them in a single sweep:
Ctrl+click to select cells within the same, single column.
Shift+click (or Shift+Arrow keys) to select contiguous cells across multiple columns and/or rows.
Click&drag to select multiple contiguous cells within the same, single row.
To quickly set the transparency for all object types on a specific layer, simply click on the layer name cell to select the entire row, then use the controls to set the desired transparency. Conversely, to quickly set the transparency for a specific object type across all layers, simply click on the object name cell to select the entire column, then use the controls to set the transparency as required.