Parent Page: PCB Objects Show
A Polygon Pour (brighter red) being used to create a large GND area on a board. SummaryA polygon pour is a group design object that is made up of simpler primitive objects. Polygon pours are used to create a solid or hatched (lattice) area on a PCB layer, using either Region objects or a combination of Track and Arc objects. Also referred to as copper pours, polygon pours are similar to a region except that they can fill irregularly shaped areas of a board as they automatically pour around existing objects, connecting only to objects on the same net as the polygon pour. On a signal layer, you can place a solid polygon pour to define an area for carrying large power supply currents, or as a ground-connected area for providing electro-magnetic shielding. Hatched polygon pours are commonly used for ground purposes in analog designs. AvailabilityPolygon Pours can only be placed in the PCB Editor. You can place them directly or create them from selected primitives. To place a polygon, switch to the required layer then perform one of the following:
PlacementAfter launching the command, the cursor will change to a cross-hair and you will enter polygon pour placement mode.
Additional actions that can be performed during placement are:
While attributes can be modified during placement (Tab to access the Properties panel), keep in mind that these will become the default settings for further placement unless the Permanent option on the PCB Editor – Defaults page of the Preferences dialog is enabled. When this option is enabled, changes made will affect only the object being placed and subsequent objects placed during the same placement session. Placement Modes
Press Shift+Spacebar to cycle through the five available corner modes; press the 1 shortcut to toggle placement between two edges or one edge. Defining a Polygon from Selected ObjectsAs well as interactively placing a polygon, they can also be created from a set of existing track and arc objects that define a closed shape. To define a polygon from an existing closed shape:
The polygon will be created with its Fill Mode set to Outline. Note that the original selected primitives are not removed and the new polygon is poured inside the selected objects. Double-click to repour the new polygon as solid or hatched. Note that the edge of the new polygon will lay along the centerline of the selected objects that were used to create it. As the Create Polygon from Selected Objects algorithm uses the centerline of the selected objects, it requires that the end and start locations of touching objects are exactly co-incident (at the same location). If this is not the case, a Confirm dialog will appear, giving the location where the algorithm failed and also providing the opportunity to instruct the algorithm to attempt to define the polygon from the edges of the objects instead. As long as the selected objects overlap slightly, this option should create a polygon with the edge of the polygon tracing the outer edge of the selected objects. Graphical EditingThe following sections describe a number of commands available to graphically modify a polygon. Move Polygon VerticesPolygons contain two points or "handles" with which to edit the shape of the polygon.
An existing polygon can be reshaped by moving these handles, or vertices, located at each corner or at the center of each edge. To modify the polygon shape:
The top images show empty handle editing. In the bottom images, Ctrl has been clicked while grabbing the handle to move for editing.
Modify Polygon BorderIn addition to vertex editing, you also can use the Polygon Actions » Modify Polygon Border right-click command to easily change the shape of polygons. Once the command is launched, the cursor becomes a crosshair. Each time you click, a new vertex is added. As during polygon placement, the Shift+Spacebar shortcuts can be used to change corner shapes. Polygon Pour CutoutTo create a cutout or hole inside a polygon, place a polygon pour cutout on top of the existing polygon. To do this:
The cutout exists as an independent object; it can be moved, resized or deleted if required. Remember that the polygon must be repoured whenever the cutout is changed. Slice Polygon PourAn existing polygon can be sliced into two smaller polygons. To do this:
Since these are now two independent polygons, each can be edited and repoured as required. Since the slicing line is the same color as the polygon, it helps if the polygon is repoured with the Fill Mode set to outline before starting the slicing process so the slicing line can easily be seen. Combining Selected Polygon Pours Two or more polygon pour objects can be combined by performing the following sequence of actions:
The new polygon properties are copied from the first selected polygon in each colliding group. Subtracting Selected Polygon PoursOne or more polygon pour objects can be subtracted from another 'base' polygon pour by performing the following sequence of actions:
If attempting to graphically modify an object that has its Locked property enabled, a dialog will appear asking for confirmation to proceed with the edit. If the Protect Locked Objects option is enabled on the Schematic – Graphical Editing page of the Preferences dialog, and the Locked option for that design object is enabled as well, then that object cannot be selected or graphically edited. Click the locked object to select it then disable the Locked property in the List panel or disable the Protect Locked Objects option to graphically edit the object. Non-Graphical EditingThe following methods of non-graphical editing are available: To select or edit a polygon, first switch to the layer on which the polygon is located. Via the Properties PanelProperties page: Polygon Pour Properties The properties of a Polygon Pour can be edited in the PCB editor's Properties panel, which allows editing of all item(s) currently selected in the workspace. During placement, the panel can be accessed by pressing the Tab key. To access the properties of a placed Polygon Pour:
Polygon Fill ModesThe polygon pour placement engine can construct polygons from either solid regions or from a combination of tracks and arcs. To help you decide which of these to use, consider the following:
Remove Islands Less ThanRemove any areas of copper that are less than the specified area. This option is area-based only; it does not consider if that island is connected to a pad or via. Note that all small unconnected areas of copper are always removed if the Remove Dead Copper option is enabled in the Properties panel. Arc ApproximationIn a region-based polygon, circular holes are approximated by a series of straight edges. Reducing this value will result in a larger number of straight edges being used to give a better approximation of an arc. Remove Necks When Copper Width Less ThanUse this to remove narrow slithers of copper. Note that when this option has a larger value, there will be a greater number of tight locations where the polygon cannot pour. The value should not be smaller than the narrowest track width that the fabricator can support. As a guide, it can be set to be the same as the narrowest track width used on the board. Net Options
Hiding and Restoring Polygons (Shelving and Unshelving)To perform design tasks within a polygon, such as repositioning a component or moving routing, the polygon can be Shelved. Shelving a polygon does not remove it from the design; it is simply hidden from display and the DRC and net connectivity analysis engines.
Repouring PolygonsIf you have changed the design within a polygon, once it has been restored it will need to be repoured to clear any violations created by the design changes. To repour polygons, click the appropriate Repour command Tools » Polygon Pours » Repour nn. Editing via a List PanelPanel pages: PCB List A List panel allows you to display design objects from one or more documents in tabular format, enabling quick inspection and modification of object attributes. Used in conjunction with appropriate filtering, it enables the display of just those objects falling under the scope of the active filter – allowing you to target and edit multiple design objects with greater accuracy and efficiency. Which key will demote the text and shape when using the Smartart text pane?You can also demote and promote shapes from within the task pane. With the insertion point in the task pane, press the Tab key to demote a shape. Press the Backspace key (or Shift+Tab) to promote a shape.
Which key can you use to size a picture proportionally?To maintain an object's proportions while resizing it, press and hold the SHIFT key while you drag a corner sizing handle.
Which tool should you use to cut away certain portions of a selected picture?Select the lasso tool from Photoshop's toolbox menu. When you click the lasso, you'll have the option to choose the regular lasso, the polygonal lasso or the magnetic lasso – each one works a little differently, but they all let you outline a shape.
What is the purpose of the eight boxes around the perimeter of an object?What is the purpose of the eight boxes around the perimeter of an object? These are called handles and they indicate the object is selected for changes.
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