Our software currently uses the fixed function pipeline in Direct3D9 to offer our users an easily scriptable way of throwing lights and objects into a simple scene. We allow directional, point and spot lights. I'm trying to move us over to Direct3D11, but I want it to be as close to the Direct3D9 fixed function pipeline as possible as a baseline. We can add stuff like per-pixel lighting later. I'm brand new to shader coding and even though I've been doing C++ for years, I feel out of my element. I'm wondering if there is a DX11 supported shader out there which perfectly emulates the lighting offered by DX9 fixed function pipeline. I have seen the old point-light emulation example in FixedFuncEMUFX11, and I'll be trying to use that as a base, but I just know I'm not doing this as efficiently as it could be, and the math for proper spot light emulation is beyond me. Is there any open source out there which emulates the fixed function pipeline, or would contain directional, point, and spot light implementations for DirectX11/10? I think all I'd need are the .fx or .hlsl files. Even if it tops out at 8 light sources, that'd be fine.
I'm currently using DirectXTK as a guide to proper DirectX11 programming, but if there is a better standard to code to, I'd love to see an example of industry standard DirectX11 rendering engine programming methodology. Thank you for any advice you can give.
For basic rendering with Direct3D 11, the DirectX Tool Kit built-in shaders are based on the XNA Game Studio 4 which provides a good set of basic features including directional lighting and per-pixel lighting. They are designed to work with all Direct3D Feature Level hardware, so they don't implement things like spotlights which are easily done with more modern hardware.
The FixedFuncEMU11 sample is a Direct3D 11 port of the legacy DirectX SDK's FixedFuncEMU Direct3D 10 sample. The shaders are useful for understanding the various Direct3D 9 specific fixed-function pipeline, but doesn't cover 'standard' stuff like implementing standard lighting models in HLSL. Also note that this sample uses the Effects system for Direct3D 11 which has it's own issues. Still, it's useful for seeing:
You might want to try some of the old Direct3D 9 era introductions to HLSL shader programming. While not 100% compatible with Direct3D 11, they are pretty close and HLSL itself is basically the same. I found this article for example.
There are also a number of excellent Direct3D 11 books all of which cover HLSL shaders since there's no fixed-function pipeline in Direct3D 11. See Book Recommendations for some details and notes as some of those books were written before the DirectX SDK was retired. In particular, you should look at Real-Time 3D Rendering with DirectX and HLSL by Varcholik as it's heavily focused on HLSL authoring.