But having their own software still gives them an edge - that's why some companies are actually going the other way entirely - like Weta writing Manuka renderer

But having their own software still gives them an edge - that's why some companies are actually going the other way entirely - like Weta writing Manuka renderer and Animal Logic writing their Glimpse renderer. It allows them to iterate extremely quickly on-depand for shows that have issues and design things properly, instead of shoe-horning existing (and often badly designed and implemented) open source software that can do simple stuff, but wasn't designed with full flexibility in mind. Different pipelines work in completely different ways, and what works for one studio doesn't necessarily work well for another. However, I do agree in principle that given a clean start (Which is never going to happen given the hundreds of thousands of lines of code VFX studios have in plugins for proprietary systems) it would make sense for all VFX studios to share a loose framework application that very flexible and advanced plugins can be written for. Image Engine's Gaffer is probably the best fit currently. In some respects it looks like Fabric Engine might at some point fit this bill, however it's not open.