Volume Rendering Dataset Loader (VTI)

Overview

How to Use

• Load a dataset: Choose a .vti filename from the Dataset dropdown and click Load.
• Rotate / Zoom / Pan:
  • Left-drag to rotate the volume.
  • Scroll (wheel / trackpad) to zoom.
  • Right-drag (or Ctrl/Cmd + drag) to pan (if enabled).
• Adjust opacity curve: The 1D opacity editor shows draggable control points (value on x-axis, opacity on y-axis).
  • Drag a point vertically to increase/decrease opacity for that scalar neighborhood.
  • Drag horizontally to retarget the scalar value where a ramp starts/peaks.
  • Add (if supported) by clicking in empty space; remove by Alt/Option-click (or as per your UI).
• Isolate structures: Lower opacity for broad background ranges (often low scalar values) and raise opacity sharply for the narrow band where the target feature’s intensities lie.
• Refine contrast: Use small, steep ramps (narrow spacing between points) to make thin or dense features “pop”; flatten (reduce) ramps to hide clutter.
• (Optional color modes): Sequential, Diverging, Categorical buttons only recolor; they do not reveal new structure—focus on opacity shaping.

Tooth-Finding Challenge

1. Start broad: After loading the dataset suspected to contain the tooth, flatten (lower) the first portion of the opacity curve so low-intensity background becomes transparent.
2. Locate candidate band: Slowly raise a narrow peak (two close control points forming a steep ramp) that sweeps across the scalar axis—watch for a compact, tooth-like form to emerge.
3. Refine edges: Tighten the ramp (move the two points closer) to sharpen boundaries; if the feature washes out, you overshot—slide the ramp slightly left/right to re-target the scalar band.
4. Suppress noise: Drop opacity of any adjacent bands that create haze or occlude the tooth silhouette.
5. Confirm: Rotate the volume to verify the feature maintains a consistent solid shape from multiple angles (not just a coincidental overlap of residual voxels).
6. Document: Note the scalar value range (x positions of the ramp points) and the approximate opacity peak you used; this parameter set is your “recipe” for revealing the tooth.

Goal: Produce a clear, stable visualization where the tooth is distinct and surrounding material is largely transparent.