CorelDraw X4 Review Part 3

This month we are going to look at the upgrade to the trace function that Corel has included with the new suite. If you have been using X3, Corel’s previous release you know that the trace function was revamped. The new trace function in X3 was awesome. That is as long as the artwork that we have received is good. In X4 Corel has added a new feature to the trace function. This new function is the centerline trace. The idea behind the tool is to create a single line instead of the usual inside and outside line that is created when we do an outline trace. CorelDraw’s definition of the centerline trace is as follows …”The Centerline Trace method uses unfilled closed and open curves (strokes) and is suitable for tracing technical illustrations, maps, line drawings, and signatures. This method is also referred to as “stroke tracing.”

Now that we have defined what a centerline trace is used for let us review the tool by going through some samples. So get out your computer and fire up your new version of X4.

The quality of any vector conversion software can only be measured by comparing an original vector object to the traced image of that same object (we would take the vector object and convert it to a bitmap). Figure 1 shows us a logo that I downloaded off the web. This logo is a good quality vector image. The vectors are “clean”. You cannot draw this logo any better.

Figure 1

Figure 2 shows the logo in figure 1 converted to a black and white bitmap image. I have converted it to 300 dpi via the “convert to black and white” command that is found in CorelDraw under the BITMAP section. This image in figure 2 represents the best image that you could scan as long as the scanned artwork is of good quality.

FIgure 2

Figure 3 shows the traced logo (figure 1) on top of the original trace. As hopefully you can see in figure 3 the two traces match up perfectly. There is a few small minor “blemishes” but these are minor and not noticeable on most material.

Figure 3

X3 gave us the perfect outline trace tool that always provides a perfect and exact copy of our original scan. So what did X4 offer us? Well it offered us “center line” trace. Why is center line trace good for us? Well for rotary engravers it is somewhat considered the holy grail of scanning.  Typically rotary engravers would rather work with “stick” style images. Remember our discussion on fonts last month. Outlines are not always good and typically rely on  us having to place a fill inside the outline. Figure 4 shows us a zoomed in look of a vectored scan. This trace creates an outline trace. The problem here is that we cannot control the width of the engraving because it is an outline trace. A centerline trace would create a single line and thus allow us to vary the width of the engraved line by varying the width of our tool.

Figure 4

Working with the Centerline function

How about if we want to run our cutter so that it creates one line instead of a so called “outline object” of our image. Creating this so called center line trace allows us to vary the line thickness by the cutter that we care going to use. For comparison sake I will re use the simple image that was used in Figure 4.

Creating a center line trace is the same as creating an outline trace. It is best to start with a black and white bitmap image. Figure 5 shows us the image that I want to start with. The status bar indicates that I have a monochrome (black and white) bitmap.

Figure 5

To do a centerline trace select the bitmap as it has been done in Figure 5. Next select the “Trace” function that is listed in the property bar at the top of our CorelDraw workspace. As per figure 6 once the fly out is opened move your mouse so that we have the “Line Drawing” command highlighted. Select it.

Figure 6

You are presented with a menu command as per figure 7. As I mentioned when I reviewed the Trace function in my CorelDraw X3 review, I like my view to be set to wireframe overlay. This view maximizes the image size and shows me the trace on top of the original image. This helps me review the Trace as best I can. For the most part I just use the defaults that come up in the Trace function (red box) in figure 7.

Figure 7

As you can see from Figure 7 the centerline trace is pretty exact when it comes to the actual trace. The only real issue is at the “peak” of the image where the trace is rounded and at the ends where the line ends to early. Figure 8 shows 3 different images of the top of our Harley logo. The top object is the original image. The red line is the object created when we did the contour offset. As you can see this image is an exact duplicate of the original object. The blue line is the center line traced object. Again it is close to the contour offset but lacks a little in the middle where the peak is more “rounded”.

Figure 8

Center Tracing a Signature

When I talked to Corel in a few of the meetings that we had they always said that centerline trace had first been created to help in creating single line signatures. Considering this was the main reason for creating the center line trace you would hope that when it comes to tracing signatures than it would be flawless. Figure 9 shows my signature on a piece of paper. Note: it is always advisable to create your signature in black ink on white paper. Make sure that when you scan it in that it is scanned in as a black and white image.

Figure 9

Figure 10 shows the centerline trace window opened with my signature displayed. You can see that the quality of the trace is pretty close. Again adjusting the trace controls did not create a better image than the default settings.

Figure 10

Figure 11 shows the two signatures separated. The black signature is our original while the red signature is our traced image. Engraving this signature (the red one) will create an image quite similar to the original. You can now use either a scratch diamond or a rotating cutter to create a “wider” signature.

I have center line traced a number of signatures over the past while testing this feature and found that the center line trace was quite accurate in recreating any of the signatures.

Figure 11

Tracing Text

One of the main reasons that I wanted to use the center line trace was to trace text – especially text in logos and cad drawings.  One of the main problems with tracing logos is that the logo may come alright but the text is an outline (see figure 12). As I mentioned earlier when we trace a black and white image we get an outline of the image that we are tracing. Basically we have a traced line that travels all around the outside of the image. Figure 12 shows us what I mean. You can see that any fill has been removed that was in the middle of the image. If I was to run this job on my rotary engraver then I will have what we call an “outline” image.  If I was to use a rotary cutter on the figure 12 text than our text will not be engraved properly as our cut lines will start to run into each other. Typically when it comes to creating a logo like this I would trace the logo, delete the text and place in a proper engraving font. Some have touted that centerline text would be great to recreate text. So can text be properly centerline traced?

Figure 12

Figure 13 shows some text that I created in CorelDraw to trace. I have shown the initial outline of the text. The text is Arial and has been bolded. I will black fill it.

Figure 13

Figure 14 shows us the original image that we are going to center trace. I have taken the text and converted it to a black and white bitmap. Converting the image into black and white makes it like a scanned image.

Figure 14

Select the image in figure 14. Select the center line trace function (“LINE DRAWING”) from the pull down menu. You can just use the default settings. Figure 15 shows the traced text outlined in red. As you can see the center line trace has done not a bad job but it is not something that I want to reproduce for a customer.

Figure 15

Logo

If you are scratch engraving one way to speed up your logo creation would be to create a centerline recreation of your logo. A centerline trace would speed up your engraving job as it would reduce the length and in some cases number of objects that are needed to recreate the logo. We can recreate our Royal Canadian Airforce logo that is seen in figure 12. Figure 16 shows the center line recreation of the logo.

As is hopefully apparent in figure 16 this is not a logo that I want to use. Parts of the logo are fine but when compared to the outline traced image in figure 12 than there no comparisons. The outline logo wins out. Thus, if we want to create “engraving” style text than we will need to remove the text and retype our engraving text into the logo. The centerline trace is not a good alternative when it comes to logos and text.

Figure 16

Although the centerline trace is not as good at creating a good centerline trace as the outline trace it does excel at some other type of images or logs. Figure 17 shows a picture of Texas that I download off the net (this image was a .gif file. I converted it to black and white in CorelDraw and resampled the resolution up to 300 DPI).

Figure 17

If I was to do an outline trace of this image I would get an inside and an outside line. If I was rotary engraving this image it would not look as good as a single line representation of the map. The center line trace of the map will create the ideal logo. Figure 18 shows the centerline trace of the logo. As you can see the trace does an excellent job. How about if you want to cut this image out on your laser? You have a perfect cut line.

Figure 18

We have spent this month’s topic discussing the centerline function that has been added to the Trace function in CorelDraw X4. To me centerline tracing is somewhat like that Holy Grail in that you always hope for knowing full well that it will never be fully mastered. Not because Corel and others cannot create software to do it. Certainly Corel has proved with the outline trace function that they can create good vectoring software. However certain images work better in center line and other in outline. The same can be said for outline traces. Corel touts the centerline trace function for scanned line drawings. Well this works only for certain objects in the drawing such as circles and lines (a filled circle does not work). Introduce filled arrows and text and your drawing will not benefit from the centerline trace. My verdict on this tool is mixed. Yes it does not do a good job on every type of image but on certain types of images it is excellent. If you want to trace line drawings like the map of Texas this tool is excellent. However complicated logos like the air force logo need to be done with the outline tool.