etonbears wrote:

I think Timon is talking about an OpenGL ADZO renderer for Linux and maybe the Mac, if Apple pull their finger out on modern OpenGL support.OpenGL is a very long-standing collection of APIs that allow you to write many different styles of renderer.If you use the oldest OpenGL APIs, you get very little direct access to the graphics hardware, as the driver does a lot of "standard" graphics work for you. The advantage of these old APIs is that you need write less code yourself, but the disadvantage is that you get less control/flexibility over exactly how the code operates. The OpenGL driver can introduce a very large overhead as it carefully checks and validates data, and doesn't really understand your application's data layout, so it has a hard time optimising performance.The newer OpenGL APIs, particularly since version 3.x have gradually moved to exposing the hardware more directly, so you write shaders that compile and run on the graphics card and access resources on the graphics card through manipulating memory buffers. If you write a renderer using only the newest OpenGL APIs, the OpenGL driver does much less work ( low overhead ), expecting you to manage and marshal your data into the form that will run shaders at their optimal speed.This trend in OpenGL coding has been called AZDO - Approaching Zero Driver Overhead. However OpenGL is not alone; all graphics APIs are moving in that direction at the moment. D3D12 will also aim to lower Windows' graphics overhead, Apple will introduce their Metal API, and AMD's hardware-specific low-overhead Mantle drivers are already in use in several Windows games.It is unlikely that the Windows code for Rebirth will be converted to use OpenGL, since the company is small, and all the low-level coders except Timon are probably Microsoft-only, or Microsoft-mainly. It may also become more difficult to produce Apple OpenGL code if they choose to focus on their own API, so I expect Timon is likely to focus on getting something working well under Linux.It doesn't mean it is impossible for Timon to write a cross-platform, OpenGL based version of Rebirth, but it's going to be a lot of work to get it working well just in Linux.Personally, I think a small company like Egosoft would be better off developing a platform-neutral codebase as much as possible as a hedge against future platform-limiting behaviour, and simply because it would be overall more time-efficient, as well as find more bugs, more quickly. But that is not where they have come from, and not where the bulk of their expertise probably lies; so the inertia for this is very great......unless, of course, Timon manages a miracle port that runs on all platforms, and faster than the original