MedicalVisualization
Pixel Based Iso-Contouring
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Determine iso line on a pixel based grid:
- Interprete the scalar grid values as height values, forming a height field
- Compute the footprint area of the iso line of thickness one pixel by projecting the iso line onto the grid base
- Calculate overlap of iso line foot print with the area of each pixel
Without line anti-aliasing:
- If overlap is more than 50%, color the pixel black
- Results in “jaggies”
With line anti-aliasing:
- Overlap ratio determines the anti-aliased color of the pixel
- Results in “blurred gray-scale line”
- Double footprint size to 2 pixel to account for blurring (1 pixel core size, and half pixel border size)
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