can you create an inside/outside algorithm for a body defined only by 961 points of its surface? This should be done in Excel/VBA. A second task is to map any color outside the body to a point on its surface.
Color Theory Background
The CIELAB color space has an irregular surface (gamut) which is defined by so-called "rectangular colors" - these are spectral distributions with 1 maximum (100 per cent) and 1 minimum reflectance (0 per cent). The following picture shows the result for spectral steps of 10nm:
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For example, a value of Lab (0, 50, 50) is not inside the body, the algorithm should detect this and map it on the surface.
It will be a possibility combine the surface colors by lines and by this create surface triangles that altogether create the body hull. This way, there will be many edges on the hull, maybe you have an idea to create a smoother surface.
How should a color outside be mapped?
HLC are the polar coordinates of Lab values and they can be interpreted as Hue (base color), Lightness and Chroma (saturation).
The most important factor of a color is its base color (Hue), and the second one is its lightness. Thus, a color outside should be mapped to a surface point with same hue and lightness, and less chroma.
The project attached files
You find an Excel file with (rectangular) Lab and (polar) HLC values of the body's surface colors. Please create a VBA module that can differ inside/outside and map outside to a value on surface following the above rule.
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