There are four tetrahedra and one box.
- Blue, opaque, single-sided (move the camera inside, you will not
see blue faces).
- Green, opaque, double-sided (move the camera inside, and you
will still see its green faces).
- Red, transparent, double-sided (you can see back faces through
the front faces).
- Yellow, transparent, single-sided (no faces are visible through
the transparent front faces).
- Purple, opaque, single-sided box (you can look through the walls
from the outside).
There are two sliders: "Modulated opacity" and "opacity". Changing
their values will change the opacity of the meshes.
- Modulated opacity: the final opacity of each tet is the product
of the slider value and the original transparency.
- Opacity: the final opacity is this slider's value, regardless
of the original transparency.
Either slider can be manipulated at any time. The last slider
modified determines the opacity rule currently exhibited.
Note: when transparent objects lie within transparent objects,
there are view-dependent artifacts (visibility and color changes).
Opacity shown: glTF transparency.