The Create Knockouts function masks parts of features that are covered by text or points. The knockouts can be created for any MAP Layer. A knockout is created for all text or point features of the selected knockout layer. All features in the selected layers will be affected by the function.
The opacity of knockout masks can be set in the Create Knockouts dialogue box and can be modified afterward through the Adobe Illustrator Transparency panel.
By default, the size of the knockouts corresponds to the Adobe Illustrator text bounding box—that includes ascenders and descenders (e.g. bottom of letter g). This size can be increased by adding a buffer in pixels (side, top and bottom) or limited to the height of capital letters. Optionally, choose the knockout to correspond to the shape of the text. This allows for finer control over the appearance of the knockouts.
Create Knockouts can either append new knockouts to the selected feature layer or replace the existing ones. It is also used to clear knockouts that were previously created with the function.
Any text layer can be used to create knockouts, it does not have to be generated by MAPublisher Labeling functions. The Feature and Text layers do not have to be in the same MAP View.
Create Knockouts requires any type of MAP Layer and a knockout layer of Text or Point type to be unlocked and visible.
Text and features that are not supposed to be masked must be moved to a different layer beforehand.
Using Create Knockouts
To access the function, click the Create Knockouts button on the MAPublisher toolbar or from the menu Object > MAPublisher > Create Knockouts.
In the Create Knockouts dialogue box, click the Select Layers button to choose at least one Layer (visible and unlocked) and then choose either a Text or Point layer from the Knockout layer drop-down. Text or points in the selected knockout layer should overlap with some of the features in the selected feature layer to get reasonable knockout results.
The Mask Opacity option sets the opacity of the masks created behind the knockout layer: a 100% setting creates an opaque mask (the feature will be invisible behind the text) and a 0% setting does not hide any features at all.
Replace Existing Knockouts
The Replace existing knockouts option clears the existing knockouts on the selected layer before adding new knockouts. This is useful when running Create Knockouts again after adjusting settings. To append the new knockouts to the existing one, make sure this option is not checked.
Knockout boxes can be created which are similar to Adobe Illustrator text bounding boxes. That bounding box can be slightly taller than the characters in the selected text because it takes into account the size of ascenders and descenders (e.g. | and g characters). To increase the size of the knockout box, four buffer options are available: Left Buffer, Right Buffer, Top Buffer and Bottom Buffer. Buffer sizes are entered as pixel values or as a different unit. The Limit to cap height option reduces the knockout size to the height of the capital letters. For example, this option is useful when labeling contour lines that are close to one another where the regular knockout size could create masks that overlap from one contour to the next. Optionally, use the Round corners using radius option to round knockout box corners. The knockout boxes are represented below by the dashed line (for visual reference only).
To achieve a knockout that does not conform to a box, choose the Text shaped knockout option and specify a buffer size. This creates a knockout that is based on the shape of each text character. It allows for finer knockout control.
Text shaped knockouts may increase document file size.
To allow for art features to show through the counter of letters with enclosed spaces, use the Draw shape around text utility. See Text Utilities.
Symbol shaped knockouts option for points is achieved using a similar approach. Specify a buffer size and optionally use the Set shape detail control to fine-tune how much detail is allowed in the knockout.
Creating knockouts for complex or 3D symbols may not produce expected results or may not be processed correctly.
All art on the specified Layers are masked or knocked out by the text or point objects, where appropriate.
To achieve the knockout effect, Create Knockouts applies an opacity mask at the layer level as can be seen in the Adobe Illustrator Layers panel.
This masking does not affect the MAP Layer attributes or properties.
Edit Knockout Masks Opacity
The opacity of all the knockouts within MAP Layers can also be edited using the Adobe Illustrator Transparency panel:
- In the Adobe Illustrator Layers panel, click the target button next to the master layer name.
- Choose Window > Transparency to open the Transparency panel.
- In the Transparency panel, click the right-side preview to start editing the opacity mask.
- Click the left-side preview in the Transparency panel to exit the opacity mask editing mode.
If for some reason the knockouts are not selected when you exit the opacity mask editing mode, the next time you return to this mode, they will not be selected by default—you'll have to select the knockouts again from within the opacity mask editing mode (click the object or use the Layers panel target button).
Clear Knockout Masks
Open the Create Knockouts dialogue box, ensure that the MAP Layers that contain the knockouts are selected and click the Clear button.