Stefan Röttger

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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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