Five of these are portable across backends. "line-loop" and
"triangle-fan" are engine extensions with no modern GPU-API
equivalent — they exist because the primitive batcher has always accepted
them, and a future backend will have to emulate them (a line loop is a line
strip plus a closing segment, which is already how the WebGL path draws it).
Prefer PORTABLE_TOPOLOGIES for anything that must survive a backend
change.
How vertices are assembled into primitives.
Five of these are portable across backends.
"line-loop"and"triangle-fan"are engine extensions with no modern GPU-API equivalent — they exist because the primitive batcher has always accepted them, and a future backend will have to emulate them (a line loop is a line strip plus a closing segment, which is already how the WebGL path draws it). Prefer PORTABLE_TOPOLOGIES for anything that must survive a backend change.