Voxels rendering

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• One approach is to convert the voxels to polys (polyvoxel) and render them using the polys graphics pipeline. The polys pipeline (the one supported by OpenGL/Vulkan, 3D pipeline) is the one supported by GPUs. And it is suitable for real time rendering (and it uses the scanline rendering).
• Other one is to use ray tracing, which can be implemented as shaders, so the GPUs can also be used

One article to read:

http://raytracey.blogspot.com/2008/08/voxel-ray-tracing-vs-polygon-ray.html

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In Ray Tracing, the 2D image is computed pixel by pixel applying the physical laws of light to models in the scene. How are these models described? #13 Take a look to:

https://gist.github.com/rossant/6046463

As you can see, the rendering is done "# Loop through all pixels." And models are described with equations to find the intersections points with the rays (collision point).

[acs]

Volumetric Rendering

https://www.alanzucconi.com/2016/07/01/volumetric-rendering/ https://www.volume-gfx.com/volume-rendering/volume-model/

«This is the basic concept behind volumetric rendering: simulating how light would propagate within the volume of an object.» for example in the fragment (per pixel) shader.