How Do I Trace Animated Line Art for a Laser?
Open BeamTracer Video to Laser, load your animation, and choose PIPELINE → Tracer → Centerline to follow the middle of each stroke. Use Outline for the boundaries of filled shapes. Convert the frames, download the ILDA file, and reopen it in ILDA Viewer to inspect the paths and try a 3D Cinema preview.
The article's Centerline ILDA file, reopened in the native Viewer at 10 FPS. Cinema and Orbit Mode show the changing projection from different angles. This is a software simulation, with venue Lights off to make the green paths easier to see.
Hi, I'm Trina with BeamTracer.com. A thick line in a video has two edges. If you trace its outline, the laser can follow both of them and turn around the tip. Sometimes that's the shape you want. For a drawing made from individual strokes, following the middle can give you the intended line more directly.
When should I choose Centerline instead of Outline?
Choose Centerline for stroke drawings, wireframe-style animations, and open curves. Choose Outline when the boundary of a filled shape is the artwork. The choice changes the paths the laser follows, so compare the exported geometry as well as the source image.
| Source | Starting choice | What to inspect |
|---|---|---|
| A thick drawn stroke | Centerline | One path through its middle, with the ends left open. |
| A filled logo or silhouette | Outline | The outside boundary and any holes that matter. |
| Touching or crossing strokes | Compare both | Junctions and small branches near the intersection. |
The original Ribbon Star sample below has a closed outer curve and three open inner strokes. Download the source MP4 to compare both tracing modes on the same frames.
Original input artwork for this tutorial. The white strokes have visible thickness; the three inner curves have open ends.
How do I convert the line animation to ILDA?
Use CONVERT in Video to Laser and select Centerline in the Tracer settings. Start with enough detail to keep the curves, then simplify only after checking the preview. The sample uses a 10 FPS output so its point budget stays modest.
- Open Video to Laser, choose CONVERT, and drop the sample MP4 into SOURCE.
- Choose PIPELINE in PROPERTIES, then click the Tracer node.
- Set METHOD → Svg Parser, DETAIL LEVEL → High, and SIMPLIFY to 0.5.
- Choose TRACE MODE → Centerline, then close the node settings.
- Open ILDA Output, set Target FPS to 10 and POV Frames to 1, then close the node settings.
- Choose Convert with Pipeline and wait for Conversion Complete.
- Choose Download ILD to save the
.ildanimation.
The sample converts into 40 ILDA frames. Leave Normalizer → Threshold at 30 and Optimizer → Smoothing off for this comparison; the output color is a single green. To make the second version, change only TRACE MODE → Outline and convert again.
If Centerline isn't offered
Check METHOD. Edge Tracer emits outline paths. Choose Svg Parser or Imagetracer to use the Centerline/Outline choice shown here. Leave a visible gap between strokes that should remain separate; touching source strokes can become a junction.
How do the exported paths differ?
Open each downloaded file in ILDA Viewer and compare the 2D view at the same animation frame. Outline goes around the thick strokes. Centerline follows their middle, leaving the inner curves open.
Outline: the exported ILDA paths, shown in the native 2D Viewer. Look at the paired outer boundary and the turns around the inner stroke tips.
Centerline: the same frame sequence and output color, with a single trace through each stroke. Both technical loops play the exported 10 FPS animation.
You can also download the Centerline ILDA example and inspect it directly. The file is Format 5 (2D True Color). The Cinema camera adds a three-dimensional view of the simulated beams; it does not turn the drawing into a 3D ILDA model.
Does Centerline always reduce the point count?
No. Centerline chooses a different path through the picture; its sampling can still produce more stored points. In the supplied example's first frame, Outline has 833 points across five drawn paths. Centerline has 931 points across four drawn paths, including the open inner curves.
Choose the geometry that matches your drawing, then check the whole file's FRAME POINT LOAD. Use SIMPLIFY to remove redundant samples, or lower the output frame rate when the required point rate exceeds the selected device. Inspect the tips and bends again after simplifying. The file-health tutorial explains the Viewer checks.
How do I inspect the animation in 3D Cinema?
Load the actual exported file in ILDA Viewer, set its playback rate, then choose 3D and Cinema — Premium fog. Orbit Mode moves the camera around the simulated projection so you can see the relationship between the pattern and its light cone.
- Open ILDA Viewer and load the downloaded
.ildfile. - Expand PLAYBACK CONTROLS, set FPS to 10 fps, and choose BEAT SYNC → Off - Loop Freely.
- Choose 3D, then open SCENE in PROPERTIES.
- Set BEAM MODE to Cinema — Premium fog and choose Orbit Mode in the camera menu above the picture.
- Turn Lights off for the uncluttered green-beam view shown here, then play the animation.
- Return to 2D to compare the stroke ends, or choose EXPORT ILDA to save the ILDA file after review.
Set the Viewer to the intended playback FPS when opening an ILDA file directly. At the Viewer's initial 30 FPS, this example exceeds the selected Standard 30k point rate; at 10 FPS, its heaviest frame requires about 10.4 kpps. That rate change is separate from choosing Centerline.
A software preview has a specific job
Cinema helps you inspect the projected shape and simulated beam geometry. FILE HEALTH → VALID and a point-budget result do not certify scanner behavior or a physical installation. No laser hardware was used for these examples.
Try your own line drawing in Video to Laser, then reopen the result in the Viewer before deciding which trace to keep. For a solid logo rather than a stroke animation, follow PNG or JPG to ILDA. Downloading ILDA requires a signed-in account; the available export allowance depends on your account.