I guess the code broke the Edit feature.

To add:
P′raster.x and P′raster.y are the coordinates of the primary image (PDF, JPEG, TIF, BMP, etc) pixel associated with Pprime.

The second and third "pseudo" code blocks above, are quotes from the link.

Elsewhere, I found more definitions of "luminance" calculation using RRBGGG / 6, etc.

- Brian

The (line) curve, and its angle theta, can be used to calculate the distance along the line for the next pPrime point.
Calculate the width and height of a rectangle by dividing 2d screen image dimensions by number of primary row and column pixels.
The distance is a hypotenuse. Use trigonometry or pythagorean formula.
Or just add dx and dy to old (pPrime point.)

It is nice to find some (relatively easy) code and explanations.