20210108:
We can not find "vPosint" but created, which was a file error, we proofed.
: https://github.com/WaitrudWeber/source_zip/blob/master/display-20210108-001.zip
And we prepare "&result function" which is attached to the last of it like the below and solved temporary.
calc.subtract( &(lp), &(screen->eye), &ray );
Because of file system, we choose a stable way convinient but unsteady.
Uniform is better.
*
diversity
unsteady
