Point Types in Laser Graphics
Anchor, guide, blanking, and collinear points — what each does, when to use them, and how they appear in BeamTracer's analysis.
Open POINT CLASSIFICATION in ILDA Viewer’s advanced tools to inspect the current frame. The counts and GEOMETRY OBSERVATIONS help you find travel points and corners worth reviewing. They describe the file’s geometry, rather than certifying its hardware performance.
Not all points are created equal. Understanding the different types helps you create better content and diagnose problems.
Anchor Points (Dwell Points)
Purpose: Give galvos time to settle at corners and direction changes.
Anchor points repeat the same position so the output spends more time there. They can change how a corner appears, but the useful count depends on the point rate, projector response, content, and intended look.
Example: Repeating a square's corner coordinates holds each corner longer, while also increasing the frame's point count.
Guide Points
Purpose: Divide long blanked jumps into smaller coordinate changes.
When jumping across a large distance with the laser off, intermediate coordinates break one large jump into several smaller ones. Use the Scanner Path and Stress Heat Map to compare the result.
Example: A blanked jump from bottom-left to top-right can use intermediate points along the diagonal path.
Blanking Points
Purpose: Allow travel without visible lines.
Any point with the blanking flag set has the laser turned off. These are used for all movement between separate shapes. The scanner still moves; you just don't see the path.
See Blanking Explained for a typical blanked-transition sequence.
Collinear Points
Purpose: Control spacing along a straight segment.
Points on a straight line do not add geometric detail, but their spacing can control scan velocity, exposure, and color changes. Removing them can change projection even when the outline looks identical.
Some collinear points are intentional for color gradients. Removing them would eliminate the color transition. Check before optimizing.
Start/End Points
Purpose: Begin and end shapes cleanly.
A shape can begin with blanked records at its start coordinate and end with repeated or blanked records before travel. The useful timing is output-system specific, so inspect the file and follow the projector manufacturer's guidance.
Point Counts in Analysis
BeamTracer counts visible points and blanked points separately for diagnostics, while both kinds count toward required PPS. A high blanked-to-visible ratio can indicate:
- Scattered content with lots of travel
- Files with repeated blanked holds or guide points
- Complex multi-shape frames
Further Reading
Color Delay Explained
Why laser strokes start dark or draw faint lines between shapes, what the Color delay control does about it, and how to dial it in on your projector.
ILDA File Format Specification
Technical specification for the ILDA binary file format — headers, format codes, coordinate system, and the status byte.