How to Split Objects with the Knife Toolgilliandarby
In this tutorial you’ll learn how to use the Knife tool to split objects, groups of objects and text along straight, freehand or Bézier cut lines. When you split objects, you can choose whether to convert outlines to curves or keep them as outlines. We will also show you how to add a gap or an overlap to the new objects resulting from the splitting action.
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How to Use the Knife Tool to Split Objects
This tutorial will demonstrate a variety of ways to split and cut objects using CorelDRAW’s Knife tool.
Click on any of the images below to view full-size.
For our first example, this heart consists of two curves: the red heart-shaped curve, and a pink curve for the highlight effect.
When you activate the Knife tool, by default it will be set to 2-Point Line mode, which will slice the object along a straight line.
You can start the cut on a point along the curve, or you can start in blank space on the document. If you drag out the cut line so that it only passes through the red fill, a faint cut line can be seen and the Objects docker shows that the heart is now split into two curves. Both curves are selected.
With the Pick tool, click on a blank area of the document to first deselect everything, then select just the lower portion and move it. To move the top part, you need to select both the pink curve, which wasn’t cut, and the red part of the heart.
In addition to cutting objects, the Knife tool can also slice through groups of objects. Starting with the same heart example, this time make both objects into a group:
- Use the Pick tool to drag a selection around the heart to capture the red and pink objects.
- Right-click on the selected objects and choose Group (or use keyboard shortcut Ctrl + G).
Activate the Knife tool again, and this time choose Bézier mode for cutting.
Click points to make a jagged cut that goes through the pink highlight and double-click when finished.
This results in a group of 4 objects, because the Knife tool sliced through both objects that originally comprise the group. There are now 2 red objects and 2 pink objects.
To create a broken heart, you’ll need to select both objects within the group before moving the top and bottom portions apart.
How to Split Text
For the next example, here is some text surrounded by an outline.
Activate the Knife tool, choose the Freehand cut mode and set the level of freehand smoothing to about 80. Draw a wavy line across the text.
You can choose to turn Auto-close on Cut on or off. If you turn it on, it will close the outline along the cut edge of the text.
This operation results in two separate groups. Each group has two objects: one is the text and the other is the outline.
With Auto-close on Cut turned off:
With Auto-close on Cut turned on:
Outline Options of the Knife Tool
The Outline options allow you to choose whether to convert outlines to curves or keep them as outlines when splitting objects. By default, the Outline options are set to Automatic, which means that CorelDRAW will choose the option that best preserves the outline appearance.
To demonstrate the difference in Outline options, a wavy curve has been created with the Pen tool, with a start and end arrowhead.
After splitting this curve with the Automatic outline option, both resulting objects remain curves.
The Convert to Objects outline option would produce the same results. But using the Keep Outlines option, each part of this split object retains the same arrow properties.
Adding Gaps with the Knife Tool
The Knife tool can also add gaps. In this example we have a graphic for a window banner, and gaps are needed where the window frames will be. Guidelines have been added to mark where the gaps should be.
Activate the Knife tool and choose 2-Point Line mode, choose Gap from the Cut Span dropdown list, and set a width. Set the Outline Option back to Automatic.
Drag the cut lines along the guide lines, holding down the Shift key to keep the lines straight.
The resulting gaps are centered along the cut lines.
Adding Overlaps with the Knife Tool
For the last example, here is a graphic that is to be printed as a split front on a sports jersey. Printing this graphic will require an overlap along the center, where the two sides of the jersey will button together.
Activate the Knife tool and choose 2-Point Line mode, choose Overlap from the Cut Span dropdown list, and set a width. Set the Outline Option back to Automatic.
Holding down the Shift key, drag the cut line down along the center.
Now, if you use the Pick tool to select everything on one side of the graphic and move the selection down, the overlap can be clearly seen.
We hope you found this tutorial helpful and we would love to hear your feedback in the Comments section below. And don’t forget to visit our user galleries and show us what you’ve learned by sharing your photos, videos and creative projects with us.