Support back-face culling in SimpleGraphicsPipeline

[bonsairobo]

I believe this would only require configuration of the rasterizer field in the GraphicsPipelineDesc passed to create_graphics_pipelines.

https://github.com/omni-viral/rendy/blob/564e7e80824afc124d57c5220e57da20f12f8e8e/graph/src/node/render/group/simple.rs#L291

Edit: Also note that front-face culling is a good technique for avoiding shadow-acne while rendering shadow maps.

[bonsairobo]

I just realized that a custom RenderGroup can specify it's rasterizer.

[zakarumych]

@bonsairobo yes. In RenderGroup you can create any numbervof pipelines manually.
However adding rasterizer parameter to simple pipeline should be pretty straightforward.