I was a little confused on the difference between an isolux diagram and a goniometric digram, but the main difference is that the isolux diagram seems to be how much lighting from the light source is provided on a flat surface (in cartesian coordinates) while the goniometric diagram is how much light is coming from the light source in polar coordinates.
For reference (https://graphics.stanford.edu/courses/cs178-09/lectures/light-and-reflection-19may09.pdf) states that the goniometric diagram is the fraction of light reflected as a function of one of the relavant angles/direction, while an isolux diagram (https://iarc.uncg.edu/elight/learn/qualitative/la_sub/isolux.html) is similar to an isocontour for light.
I was a little confused on the difference between an isolux diagram and a goniometric digram, but the main difference is that the isolux diagram seems to be how much lighting from the light source is provided on a flat surface (in cartesian coordinates) while the goniometric diagram is how much light is coming from the light source in polar coordinates.
For reference (https://graphics.stanford.edu/courses/cs178-09/lectures/light-and-reflection-19may09.pdf) states that the goniometric diagram is the fraction of light reflected as a function of one of the relavant angles/direction, while an isolux diagram (https://iarc.uncg.edu/elight/learn/qualitative/la_sub/isolux.html) is similar to an isocontour for light.