what's good usecase for TransientBuffer?

[niu2x]

thanks for your time .

in some bgfx' examples, we alloc TransientVertexBuffer/TransientIndexBuffer, and copy mem to these buffer, in main loop.

is it necessary ? (eg: 03-raymarch, TextBufferManager )

what's the guideline ? what's the time to use TransientVertexBuffer instead of normal buffer.

[bkaradzic]

First definition of transient:

passing especially quickly into and out of existence

https://www.merriam-webster.com/dictionary/transient

It's special buffer type for index/vertex buffers that are changing every frame. It's there as convenience as fire&forget, so you don't have to manually manage buffers that are changing all the time. Also, as we know what's life-time of these buffers, it allows some internal optimizations.

Transient - changes every frame
Dynamic - changes sometimes (if you don't pass data on creation, buffer/texture is dynamic)
Static - never changes (if you pass data to any creation function, it's assumed that buffer/texture is immutable)

[niu2x]

i got it. thanks very much for your quick reply.