Parameters
- v1x
- First vertex's X-coordinate
- v1y
- First vertex's Y-coordinate
- v1z
- First vertex's Z-coordinate
- v2x
- Second vertex's X-coordinate
- v2y
- Second vertex's Y-coordinate
- v2z
- Second vertex's Z-coordinate
- v3x
- Third vertex's X-coordinate
- v3y
- Third vertex's Y-coordinate
- v3z
- Third vertex's Z-coordinate