Performance improvements, GPU integration and prootype for Makie integration

[SimonDanisch]

This makes Trace.jl 10-20x faster and prototypes a simple Makie integration. It also removes any allocations and dynamic dispatch to make the same code run on the GPU. Currently, the GPU version isn't much faster as the CPU though, which may require further experiments with the ray intersection implementation and removal of GPU performance traps.

using Trace, TraceMakie
begin
    model = load(joinpath(dirname(pathof(Trace)), "..", "docs", "src", "assets", "models", "caustic-glass.ply"))
    glass = Trace.GlassMaterial(
        Trace.ConstantTexture(Trace.RGBSpectrum(0.9f0)),
        Trace.ConstantTexture(Trace.RGBSpectrum(0.88f0)),
        Trace.ConstantTexture(0.0f0),
        Trace.ConstantTexture(0.0f0),
        Trace.ConstantTexture(1.4f0),
        true,
    )
    plastic = Trace.PlasticMaterial(
        Trace.ConstantTexture(Trace.RGBSpectrum(0.6399999857f0, 0.6399999857f0, 0.5399999857f0)),
        Trace.ConstantTexture(Trace.RGBSpectrum(0.1000000015f0, 0.1000000015f0, 0.1000000015f0)),
        Trace.ConstantTexture(0.010408001f0),
        true,
    )
    plastic_ceil = Trace.PlasticMaterial(
        Trace.ConstantTexture(Trace.RGBSpectrum(0.3399999857f0, 0.6399999857f0, 0.8399999857f0)),
        Trace.ConstantTexture(Trace.RGBSpectrum(1.4f0)),
        Trace.ConstantTexture(0.000408001f0),
        true,
    )
    scene = Scene(size=(1024, 1024); lights=[
        AmbientLight(RGBf(1, 1, 1)),
        PointLight(Vec3f(4, 4, 10), RGBf(150, 150, 150)),
        PointLight(Vec3f(-3, 10, 2.5), RGBf(60, 60, 60)),
        PointLight(Vec3f(0, 3, 0.5), RGBf(40, 40, 40))
    ])
    cam3d!(scene)
    cm = scene.camera_controls
    mesh!(scene, model, material=glass)
    mini, maxi = extrema(Rect3f(decompose(Point, model)))
    floorrect = Rect3f(Vec3f(-10, mini[2], -10), Vec3f(20, -1, 20))
    mesh!(scene, floorrect, material=plastic_ceil)
    ceiling = Rect3f(Vec3f(-25, 11, -25), Vec3f(50, -1, 50))
    mesh!(scene, ceiling, material=plastic)
    center!(scene)
    update_cam!(scene, Vec3f(-1.6, 6.2, 0.2), Vec3f(-3.6, 2.5, 2.4), Vec3f(0, 1, 0))

    # render_interactive(scene, ArrayType; max_depth=5)
    TraceMakie.render_interactive(scene; backend=GLMakie, max_depth=5)
end

[lazarusA]

+378,980 −1,668

This is one of the biggest PRs I have seen so far, 😄.

[SimonDanisch]

Continued in https://github.com/JuliaGraphics/Trace.jl/pull/34