c# - Finding the surface of a triangle in a cartesian cube -

i have 3 dimensional array of bit values (either 0 or 1) representing x, y , z axis (in range of 0-99) of cartesian cube. entire array initialized 0's.

additionally have triangle of points within cube identified following points.

trianglea: [
15, 22, 11,
86, 76, 67,
45, 51, 91
]


marking 3 points value of 1 easy. question this:

how mark of other coordinates of surface identified triangle value of 1 well?

basically how implement function:

public bool isonsurfaceoftrianglea(x, y, z) {

   // math goes here! :) 

}

any help/suggestions appreciated.

i use loop using this solution. simple determine min , max range , run them in double loop(from min till max)