Using filters, bitmap masks, and the highlight tool to glint the edges of text.

Requirements: Digital Fusion 3.0 and DFX+ 3.0
Flow: N/A
Images: N/A
Archive: N/A

This week we'll look at how to use a number of tools in Digital Fusion/DFX+ to create a stylized glint along the edges of an object such as a product or text. This technique can help add a little something extra to your next shot.

We will add the glint to some text. Let's start by adding a text+ tool, and setting up the font etc.

1. Start a new flow.
2. Add a text+ tool, and enter some text. Adjust the font size setting to fill the screen nicely.

3. Now add a filter tool to the flow, and set the filter to "Laplacian". This is one of the edge detect filters available in the filter tool. If the edges are not defined well, try the "Sobel" filter.

4. Next add a brightness/contrast tool. We will use this to make the edges monochrome (if not already) as well as punch up the levels.
   1. Set the gain to 5
   2. Set the saturation to 0
   3. Adjust the clip low and clip high if necessary to remove any extra lines that may be visible (other than the edges of the text.), or enhance weaker lines.

This has set up a matte of our text to limit the effect of the highlight tool that we will be adding next.

5. Add a highlight tool to the flow next. Set your angle slider to about 45 degrees. Now adjust your clip low setting until it has added a number of highlights.

As you can see the highlight tool has added the highlights, but it's hardly subtle now is it? In order to fix this we'll add an effects mask, and then a highlight mask to illustrate the differences of these two options. In this case we'll work with a bitmap mask.

6. To add a bitmap mask, we first need a bitmap that we plan to use. In this case a modified plasma tool will do the trick. Add a plasma tool to your flow separate from the main branch.

1. Open the color tab, and adjust all the sliders to 1. This will make the plasma monochromatic.

7. Add a brightness/contrast tool after the plasma, and set the clip low setting to a large value. The idea here is to clip the plasma to just a thin line to act as a mask.

8. Next ensure that you have the highlight tool active. Then right click in the large view, and choose the "effects mask/bitmap" option. You should see a blue dot appear next to the mask tab (under the small view). Open the controls for the mask, and then the bitmap controls. Drag and drop the brightness/contrast after the plasma to the area marked "drop tools here"

As you can see this has limited the effect of the highlight tool to just where the plasma crosses the outline of the text. But this isn't really the effect we're looking for, as the highlights are just nondescript waves at this point, and not truly a highlight. To fix this;

9. Right click on the header for the bitmap mask, and choose delete.
10. In the large view, (again ensuring that the highlight tool is selected) right click, and choose "highlight mask/bitmap"
11. Again, drag and drop the brightness/contrast from the plasma to the "drop tools here" area of the mask.

This time you should see now that the highlights are only being created where the plasma and edge detect cross, but is not limited to that region, and therefore bloom nicely. (You may need to adjust the clip settings under your highlight tool to increase the intensity.) The final stage of this little project will be to merge the highlights over the original text. We need to add a branch from our original text+ tool, and merge our highlights over.

12. Add a merge to your flow, not connected to anything.
13. Drag a connection from the text+ output to the background of the merge. (Brown)
14. Drag a connection from the highlight output to the foreground of the merge. (Green)

15. To tidy things up;
    1. Set your merge to additive.
    2. Uncheck the "merge over" box under the settings controls for the highlight tool.

So there you have glinting edges on your text. The reason we changed the merge to additive, is the highlight tool generates a pre-multiplied alpha. See the tip on that for further explanation. The "merge over" is changed to simply remove the outline from the final composite.

Things to try with this project would include animating the phase of the plasma so the highlights crawl along your text. You can also experiment with adjusting the color of your highlights, fading in and out of the highlights, and animating the angle.

Stay tuned for a later tip dealing with creating a highlight mask when the scene contains too much detail for the edge detection filters to work appropriately. In the meantime;