rev: 3827f53bae88e48a594610914ba74b9512ead6dd tukan/testing/test_tmt6.sc -rw-r--r-- 51.0 KiB View raw Log this file
3827f53bae88 — Leonard Ritter * more work on module system 3 months ago
                                                                                
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#
    biquadratic interpolation
    with approximate raytracing

#
    tetrahedral marching triangles

    step 1: identify by mask for each tet if its relevant vertices are partially set
    mask has 8 bits, 3 tets per bitarray = 2 x 24 bits
    all bits set or all bits not set = ignore, otherwise generate surface

    one tet is handled per thread

import ..tukan.voxel
let voxel = tukan.voxel

using import glm
using import glsl
using import Array
using import Box
using import struct
using import ..tukan.gl
using import ..tukan.bitmap
using import ..tukan.packing
using import ..tukan.random
using import ..tukan.color
using import ..tukan.perfect_hash
using import ..tukan.raytrace
using import ..tukan.sdf
using import ..tukan.sdl
using import ..tukan.rotation
using import ..tukan.brdf
using import ..tukan.mesh
using import ..tukan.normal
using import ..tukan.projection
using import ..tukan.derivative
using import ..tukan.isosurface
using import ..tukan.hash
using import .testfragment

let USE_PACKING =
    #true
    false

# regress to trilinear filtering
let USE_LINEAR_FILTER =
    #true
    false

let USE_WEIGHT_BLUR =
    true
    #false

# reserve 10MB for each voxel buffer
    at 4 bytes per voxel
let MAX_VOXELS = ((20 * (1 << 20)) // 4)

# pack quantization
let PACKING_Q = 1.0

embed
    let RAYMARCH_MINDIST = (1.0 / 64.0)
    let RAYMARCH_STEPS = 64

#embed
    let RAYMARCH_MINDIST = (1.0 / 256.0)
    let RAYMARCH_STEPS = 50

let BINDING_BUF_CELLS_IN = 1
let BINDING_BUF_CELLS_IN_INFO = 2
let BINDING_BUF_CELLS_OUT = 3
let BINDING_BUF_CELLS_OUT_INFO = 4
let BINDING_BUF_DRAW_CMD = 3
let BINDING_BUF_COMPUTE_CMD = 4
let BINDING_BUF_VERTEX_ATTR1_IN = 5
let BINDING_BUF_VERTEX_ATTR1_OUT = 6

let IMAGE_TARGET_RGBA32F = 1

let UNIFORM_LEVEL = 1
let UNIFORM_PROGRAM = 2
let UNIFORM_SCREEN_SAMPLER = 3
let UNIFORM_DIVISOR = 4

let ProgramVoxelizeInit = 0
let ProgramVoxelize = 1
let ProgramSimplify = 2

let sqrt3 = (sqrt 3.0)
let THREADSIZE = 256

let corner-vectors =
    arrayof vec3
        vec3 0 0 0
        vec3 1 0 0
        vec3 0 1 0
        vec3 1 1 0
        vec3 0 0 1
        vec3 1 0 1
        vec3 0 1 1
        vec3 1 1 1

run-stage;

struct CellValsInfo plain
    count : u32

struct CellVals plain
    # each entry holds a key
    entries : (array u32)

buffer buf-cells-in : CellVals
    binding = BINDING_BUF_CELLS_IN
    \ readonly coherent restrict

buffer buf-cells-in-info : CellValsInfo
    binding = BINDING_BUF_CELLS_IN_INFO
    \ readonly coherent restrict

buffer buf-cells-out : CellVals
    binding = BINDING_BUF_CELLS_OUT
    \ writeonly coherent restrict

buffer buf-cells-out-info : CellValsInfo
    binding = BINDING_BUF_CELLS_OUT_INFO
    \ coherent restrict

let CubeData =
    static-if USE_PACKING
        static-if USE_LINEAR_FILTER
            struct CubeData plain
                v0 : uvec4
        else
            struct CubeData plain
                v0 : uvec4
                v1 : uvec4
    else
        static-if USE_LINEAR_FILTER
            struct CubeData plain
                key : u32
                v : (array f32 8)
        else
            struct CubeData plain
                key : u32
                v : (array f32 27)

struct VertexAttr1 plain
    # cell key + simplex index, 4x u8 weights
    entries : (array CubeData)

buffer buf-vertex-attr1-in : VertexAttr1
    binding = BINDING_BUF_VERTEX_ATTR1_IN
    \ readonly coherent restrict

buffer buf-vertex-attr1-out : VertexAttr1
    binding = BINDING_BUF_VERTEX_ATTR1_OUT
    \ writeonly coherent restrict

uniform u-program : i32
    location = UNIFORM_PROGRAM

uniform u-level : i32
    location = UNIFORM_LEVEL

uniform smp-screen : sampler2D
    location = UNIFORM_SCREEN_SAMPLER

struct DispatchIndirectCommandI plain
    command : DispatchIndirectCommand

struct DrawArraysIndirectCommandI plain
    command : DrawArraysIndirectCommand

buffer buf-compute-cmd : DispatchIndirectCommandI
    binding = BINDING_BUF_COMPUTE_CMD
    \ writeonly coherent restrict

buffer buf-draw-cmd : DrawArraysIndirectCommandI
    binding = BINDING_BUF_DRAW_CMD
    \ writeonly coherent restrict

uniform u-divisor : i32
    location = UNIFORM_DIVISOR

fn setup-compute-command ()
    local_size 1 1 1
    let divisor = ((deref u-divisor) as u32)
    buf-compute-cmd.command =
        DispatchIndirectCommand
            ((deref buf-cells-in-info.count) + divisor - 1:u32) // divisor
            1
            1
    ;

fn setup-draw-arrays-command ()
    local_size 1 1 1
    buf-draw-cmd.command =
        DrawArraysIndirectCommand
            deref buf-cells-in-info.count
            1
            0
            0
    ;

fn simple-sphere (p)
    (length p) - 0.5

fn nine-spheres (p)
    let x = (deref shglobals.time)
    r := (mix 0.1 0.2 ((sin x) * 0.5 + 0.5))
    d := (sqrt 0.5) * 0.4
    sdSmoothAnd
        sdSmoothOr
            (length p) - 0.5
            min
                (length (p - (vec3 d d d))) - r
                (length (p - (vec3 -d d d))) - r
                (length (p - (vec3 d -d d))) - r
                (length (p - (vec3 -d -d d))) - r
            0.1
        * -1.0
            min
                (length (p - (vec3 d d -d))) - r
                (length (p - (vec3 -d d -d))) - r
                (length (p - (vec3 d -d -d))) - r
                (length (p - (vec3 -d -d -d))) - r
        0.1

fn twoballs (p)
    let x = (deref shglobals.time)
    x := ((sin x) * 0.5 + 0.5) * 0.5
    sdSmoothOr
        (length (p - (vec3 0.0 0 x))) - 0.25
        (length (p - (vec3 0.0 0 -x))) - 0.25
        0.2

fn doubletori (p)
    let x = (deref shglobals.time)
    let xz =
        anglevector-rotate
            anglevector -x
            p.xz
    let p1 =
        vec3
            xz.x
            p.y
            xz.y
    let p2 =
        vec3
            anglevector-rotate
                anglevector x
                p.xy
            p.z

    'sdSmoothOr
        sdmDist
            sdTorus p1.xzy (vec2 0.5 0.05)
            sdMaterial
                vec4 1.0 0.5 0.3 1.0
        sdmDist
            sdTorus p2 (vec2 0.4 0.1)
            sdMaterial
                vec4 0.3 0.5 1.0 1.0
                roughness = 0.1
        0.2

fn two-boxes (p)
    let x = (deref shglobals.time)
    let p1 =
        vec3
            anglevector-rotate
                anglevector -x
                p.xy
            p.z
    let p2 =
        vec3
            p.x
            anglevector-rotate
                anglevector (x * 0.917)
                p.yz
    'sdSmoothOr
        sdmDist
            sdBox p1 (vec3 0.33)
            sdMaterial
                vec4 1.0 0.5 0.3 1.0
        sdmDist
            sdBox p2 (vec3 0.33)
            sdMaterial
                vec4 0.3 0.5 1.0 1.0
                roughness = 0.1
        0.2

fn two-boxes-merge (p)
    let d =
        vec3 0.3
    let sz =
        vec3 0.5
    let x = (deref shglobals.time)
    r := (mix 1.0 0.2 ((sin x) * 0.5 + 0.5))
    'sdSmoothAnd
        'sdSmoothOr
            sdmDist
                #sdSphere
                    p - (vec3 0.01)
                    1.0
                sdUberprim
                    p - (vec3 0.01)
                    vec4 1.0 1.0 0.05 0.05
                    vec3 0.5 0.05 0.0
                sdMaterial
                    vec4 1.0 0.9 0.3 1.0
                    metallic = 1.0
            'sdSmoothOr
                sdmDist
                    sdBox (p - d) sz
                    sdMaterial
                        vec4 1.0 0.5 0.3 1.0
                sdmDist
                    sdBox (p + d) sz
                    sdMaterial
                        vec4 0.3 0.5 1.0 1.0
                        roughness = 0.2
                0.5
            0.05
        sdmDist
            -
                sdSphere
                    p - (vec3 0.0 0.0 -0.5)
                    r
            sdMaterial
                vec4 0.5 0.3 1.0 1.0
        0.1

fn two-boxes-merge-deluxe (p)
    let d =
        vec3 0.3
    let sz =
        vec3 0.5
    let x = (deref shglobals.time)
    let sp1 =
        p - (vec3 0.0 0.0 -0.5)
    cwave := (sin (x * 10.0 + 2.0 * pi * 10.0 * (length sp1)))
    wave := cwave * 0.5 + 0.5
    r := (mix 1.0 0.2 ((sin x) * 0.5 + 0.5))
    'sdSmoothOr
        'sdSmoothAnd
            'sdSmoothOr
                sdmDist
                    #sdSphere
                        p - (vec3 0.01)
                        1.0
                    sdUberprim
                        p - (vec3 0.01)
                        vec4 1.0 1.0 0.05 0.05
                        vec3 0.5 0.05 0.0
                    sdMaterial
                        vec4 1.0 0.9 0.3 1.0
                        metallic = 1.0
                'sdSmoothOr
                    sdmDist
                        ((sdBox (p - d) (sz - 0.1)) - 0.1 + cwave * 0.01) / 1.3
                        sdMaterial
                            mix
                                vec4 1.0 0.5 0.3 1.0
                                (vec4 1.0 0.5 0.3 1.0) * 0.3
                                wave
                    sdmDist
                        sdBox (p + d) sz
                        sdMaterial
                            vec4 0.3 0.5 1.0 1.0
                            roughness = 0.2
                    0.5
                0.05
            sdmDist
                - (sdSphere sp1 r)
                sdMaterial
                    vec4 0.5 0.3 1.0 1.0
            0.1
        sdmDist
            sdEllipsoid
                p - (vec3 0.2 0.0 0.0)
                vec3 0.3 0.4 1.0
            sdMaterial
                vec4 0.3 1.0 0.5 1.0
        0.1

fn one-box (p)
    sdBox p (vec3 0.33)

fn matmapf (p)
    #do
        p := p.yzx * 2.0
        (two-boxes-merge-deluxe p) * 0.5
    do
        p := p.yzx * 2.0
        (two-boxes-merge p) * 0.5
    #doubletori p
    #two-boxes p

# single sphere:
    256^3: 89240 cells (best: 0.3ms)
    1024^3: 1427240 cells (best: 3.5ms)
# min: 104567 at 256^3
fn mapf (p)
    #let x = ((radians (deref shglobals.time)) * 10.0)
    #let xz =
        anglevector-rotate
            anglevector -x
            p.xz
    #let p =
        vec3
            xz.x
            p.y
            xz.y
    #simple-sphere p
    #twoballs p
    #doubletori p
    #nine-spheres p
    #two-boxes p
    #one-box p
    (matmapf p) as f32

fn normalmapf (p r)
    - (sdNormalFast mapf p r)

fn subdivide-cell (key)
    let level = ((deref u-level) as u32)
    let r = (/ (f32 (1:u32 << level)))
    let d = (2.0 * r)
    #let rlimit =
        if (level == 8:u32) r
        else (sqrt3 * r)

    key := (key << 3:u32)

    ucoord := (unpack-morton3x10 key)
    coord := (vec3 ucoord) * d - 1.0 + r

    global cells : (array u32 8)
    global written = 0:u32

    fn test-cell (i ofs key coord r)
        let rlimit = (sqrt3 * r)
        key := key | i
        pos := coord + ofs
        let dist = (mapf pos)
        let hit = ((abs dist) < rlimit)
        if hit
            cells @ (deref written) = key
            written += 1:u32

    inline test-cell (i ofs)
        test-cell i ofs key coord r

    test-cell 0:u32 (vec3 0 0 0)
    test-cell 1:u32 (vec3 d 0 0)
    test-cell 2:u32 (vec3 0 d 0)
    test-cell 3:u32 (vec3 d d 0)
    test-cell 4:u32 (vec3 0 0 d)
    test-cell 5:u32 (vec3 d 0 d)
    test-cell 6:u32 (vec3 0 d d)
    test-cell 7:u32 (vec3 d d d)

    # commit
    if (written != 0:u32)
        let id = (atomicAdd buf-cells-out-info.count (deref written))
        for i in (range (deref written))
            buf-cells-out.entries @ (id + i) = (cells @ i)

fn simplify-cell (key)
    let level = (((deref u-level) as u32) - 1)
    let r = (/ (f32 (1:u32 << level)))
    let d = (2.0 * r)

    ucoord := (unpack-morton3x10 key)

    coord := (vec3 ucoord) * d - 1.0 + r

    let id = (atomicAdd buf-cells-out-info.count 1:u32)
    let data = (buf-vertex-attr1-out.entries @ id)

    static-if USE_PACKING
        static-if USE_LINEAR_FILTER
            inline get (x y z)
                ofs := ((vec3 x y z) * r)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            data.v0 =
                uvec4
                    key
                    packSnorm4x8
                        vec4
                            get -1 -1 -1
                            get  1 -1 -1
                            get -1  1 -1
                            get  1  1 -1
                    packSnorm4x8
                        vec4
                            get -1 -1  1
                            get  1 -1  1
                            get -1  1  1
                            get  1  1  1
                    0
        elseif USE_WEIGHT_BLUR
            inline get (x y z)
                ofs := ((vec3 x y z) * d)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            let
                p000 = (get -1 -1 -1)
                p001 = (get  0 -1 -1)
                p002 = (get  1 -1 -1)
                p010 = (get -1  0 -1)
                p011 = (get  0  0 -1)
                p012 = (get  1  0 -1)
                p020 = (get -1  1 -1)
                p021 = (get  0  1 -1)
                p022 = (get  1  1 -1)

                p100 = (get -1 -1  0)
                p101 = (get  0 -1  0)
                p102 = (get  1 -1  0)
                p110 = (get -1  0  0)
                p111 = (get  0  0  0)
                p112 = (get  1  0  0)
                p120 = (get -1  1  0)
                p121 = (get  0  1  0)
                p122 = (get  1  1  0)

                p200 = (get -1 -1  1)
                p201 = (get  0 -1  1)
                p202 = (get  1 -1  1)
                p210 = (get -1  0  1)
                p211 = (get  0  0  1)
                p212 = (get  1  0  1)
                p220 = (get -1  1  1)
                p221 = (get  0  1  1)
                p222 = (get  1  1  1)

            let CF = (/ 8.0)
            let EF = (/ 4.0)
            let FF = (/ 64.0)

            # we're reweighting the SDF to match barycentric quadratic interpolation
            # stream reweighted SDF to output to avoid too many temporaries

            data.v0 =
                uvec4
                    key
                    packSnorm4x8
                        vec4
                            (p000 + p001 + p010 + p011 + p100 + p101 + p110 + p111) * CF
                            (p001 + p011 + p101 + p111) * EF
                            (p001 + p002 + p011 + p012 + p101 + p102 + p111 + p112) * CF
                            (p010 + p011 + p110 + p111) * EF
                    packSnorm4x8
                        vec4
                            (28 * (p111 + p011) + 2 * (p001 + p010 + p012 + p021 + p101 + p110 + p112 + p121) + p002 + p020 + p102 + p120 - 3 * (p000 + p022 + p100 + p122)) * FF
                            (p011 + p012 + p111 + p112) * EF
                            (p010 + p011 + p020 + p021 + p110 + p111 + p120 + p121) * CF
                            (p011 + p021 + p111 + p121) * EF
                    packSnorm4x8
                        vec4
                            (p011 + p012 + p021 + p022 + p111 + p112 + p121 + p122) * CF
                            (p100 + p101 + p110 + p111) * EF
                            (28 * (p111 + p101) + 2 * (p001 + p011 + p102 + p110 + p112 + p201 + p211 + p100) + p002 + p012 + p200 + p210 - 3 * (p000 + p010 + p202 + p212)) * FF
                            (p101 + p102 + p111 + p112) * EF
            data.v1 =
                uvec4
                    packSnorm4x8
                        vec4
                            (28 * (p111 + p110) + 2 * (p010 + p011 + p100 + p101 + p120 + p121 + p210 + p211) + p020 + p021 + p200 + p201 - 3 * (p000 + p001 + p220 + p221)) * FF
                            (184 * p111 + 20 * (p011 + p101 + p110 + p112 + p121 + p211) + 6 * (p012 + p021 + p102 + p120 + p201 + p210) + p002 + p020 + p022 + p200 + p202 + p220 - 10 * (p001 + p010 + p100 + p122 + p212 + p221) - 15 * (p000 + p222)) * CF
                            (28 * (p111 + p112) + 2 * (p011 + p012 + p101 + p102 + p121 + p122 + p211 + p212) + p001 + p002 + p221 + p222 - 3 * (p021 + p022 + p201 + p202)) * FF
                            (p110 + p111 + p120 + p121) * EF
                    packSnorm4x8
                        vec4
                            (28 * (p111 + p121) + 2 * (p011 + p021 + p110 + p112 + p120 + p122 + p211 + p221) + p010 + p020 + p212 + p222 - 3 * (p012 + p022 + p210 + p220)) * FF
                            (p111 + p112 + p121 + p122) * EF
                            (p100 + p101 + p110 + p111 + p200 + p201 + p210 + p211) * CF
                            (p101 + p111 + p201 + p211) * EF
                    packSnorm4x8
                        vec4
                            (p101 + p102 + p111 + p112 + p201 + p202 + p211 + p212) * CF
                            (p110 + p111 + p210 + p211) * EF
                            (28 * (p111 + p211) + 2 * (p101 + p110 + p112 + p121 + p201 + p210 + p212 + p221) + p100 + p122 + p200 + p222 - 3 * (p102 + p120 + p202 + p220)) * FF
                            (p111 + p112 + p211 + p212) * EF
                    packSnorm4x8
                        vec4
                            (p110 + p111 + p120 + p121 + p210 + p211 + p220 + p221) * CF
                            (p111 + p121 + p211 + p221) * EF
                            (p111 + p112 + p121 + p122 + p211 + p212 + p221 + p222) * CF
                            0
        else
            inline get (x y z)
                ofs := ((vec3 x y z) * r)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            data.v0 =
                uvec4
                    key
                    packSnorm4x8
                        vec4
                            get -1 -1 -1
                            get  0 -1 -1
                            get  1 -1 -1
                            get -1  0 -1
                    packSnorm4x8
                        vec4
                            get  0  0 -1
                            get  1  0 -1
                            get -1  1 -1
                            get  0  1 -1
                    packSnorm4x8
                        vec4
                            get  1  1 -1
                            get -1 -1  0
                            get  0 -1  0
                            get  1 -1  0
            data.v1 =
                uvec4
                    packSnorm4x8
                        vec4
                            get -1  0  0
                            get  0  0  0
                            get  1  0  0
                            get -1  1  0
                    packSnorm4x8
                        vec4
                            get  0  1  0
                            get  1  1  0
                            get -1 -1  1
                            get  0 -1  1
                    packSnorm4x8
                        vec4
                            get  1 -1  1
                            get -1  0  1
                            get  0  0  1
                            get  1  0  1
                    packSnorm4x8
                        vec4
                            get -1  1  1
                            get  0  1  1
                            get  1  1  1
                            0
    else # no packing
        data.key = key
        static-if USE_LINEAR_FILTER
            inline get (x y z)
                ofs := ((vec3 x y z) * r)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            data.v @ 0 = (get -1 -1 -1)
            data.v @ 1 = (get  1 -1 -1)
            data.v @ 2 = (get -1  1 -1)
            data.v @ 3 = (get  1  1 -1)
            data.v @ 4 = (get -1 -1  1)
            data.v @ 5 = (get  1 -1  1)
            data.v @ 6 = (get -1  1  1)
            data.v @ 7 = (get  1  1  1)
        elseif USE_WEIGHT_BLUR
            inline get (x y z)
                ofs := ((vec3 x y z) * d)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            let
                p000 = (get -1 -1 -1)
                p001 = (get  0 -1 -1)
                p002 = (get  1 -1 -1)
                p010 = (get -1  0 -1)
                p011 = (get  0  0 -1)
                p012 = (get  1  0 -1)
                p020 = (get -1  1 -1)
                p021 = (get  0  1 -1)
                p022 = (get  1  1 -1)

                p100 = (get -1 -1  0)
                p101 = (get  0 -1  0)
                p102 = (get  1 -1  0)
                p110 = (get -1  0  0)
                p111 = (get  0  0  0)
                p112 = (get  1  0  0)
                p120 = (get -1  1  0)
                p121 = (get  0  1  0)
                p122 = (get  1  1  0)

                p200 = (get -1 -1  1)
                p201 = (get  0 -1  1)
                p202 = (get  1 -1  1)
                p210 = (get -1  0  1)
                p211 = (get  0  0  1)
                p212 = (get  1  0  1)
                p220 = (get -1  1  1)
                p221 = (get  0  1  1)
                p222 = (get  1  1  1)

            let CF = (/ 8.0)
            let EF = (/ 4.0)
            let FF = (/ 64.0)
            let BF = (/ 256.0)

            # we're reweighting the SDF to match barycentric quadratic interpolation
            # stream reweighted SDF to output to avoid too many temporaries

            data.v @ 0 = (p000 + p001 + p010 + p011 + p100 + p101 + p110 + p111) * CF
            data.v @ 1 = (p001 + p011 + p101 + p111) * EF
            data.v @ 2 = (p001 + p002 + p011 + p012 + p101 + p102 + p111 + p112) * CF
            data.v @ 3 = (p010 + p011 + p110 + p111) * EF
            data.v @ 4 = (28 * (p111 + p011) + 2 * (p001 + p010 + p012 + p021 + p101 + p110 + p112 + p121) + p002 + p020 + p102 + p120 - 3 * (p000 + p022 + p100 + p122)) * FF
            data.v @ 5 = (p011 + p012 + p111 + p112) * EF
            data.v @ 6 = (p010 + p011 + p020 + p021 + p110 + p111 + p120 + p121) * CF
            data.v @ 7 = (p011 + p021 + p111 + p121) * EF
            data.v @ 8 = (p011 + p012 + p021 + p022 + p111 + p112 + p121 + p122) * CF
            data.v @ 9 = (p100 + p101 + p110 + p111) * EF
            data.v @ 10 = (28 * (p111 + p101) + 2 * (p001 + p011 + p102 + p110 + p112 + p201 + p211 + p100) + p002 + p012 + p200 + p210 - 3 * (p000 + p010 + p202 + p212)) * FF
            data.v @ 11 = (p101 + p102 + p111 + p112) * EF
            data.v @ 12 = (28 * (p111 + p110) + 2 * (p010 + p011 + p100 + p101 + p120 + p121 + p210 + p211) + p020 + p021 + p200 + p201 - 3 * (p000 + p001 + p220 + p221)) * FF
            data.v @ 13 = (184 * p111 + 20 * (p011 + p101 + p110 + p112 + p121 + p211) + 6 * (p012 + p021 + p102 + p120 + p201 + p210) + p002 + p020 + p022 + p200 + p202 + p220 - 10 * (p001 + p010 + p100 + p122 + p212 + p221) - 15 * (p000 + p222)) * BF
            data.v @ 14 = (28 * (p111 + p112) + 2 * (p011 + p012 + p101 + p102 + p121 + p122 + p211 + p212) + p021 + p022 + p201 + p202 - 3 * (p001 + p002 + p221 + p222)) * FF
            data.v @ 15 = (p110 + p111 + p120 + p121) * EF
            data.v @ 16 = (28 * (p111 + p121) + 2 * (p011 + p021 + p110 + p112 + p120 + p122 + p211 + p221) + p012 + p022 + p210 + p220 - 3 * (p010 + p020 + p212 + p222)) * FF
            data.v @ 17 = (p111 + p112 + p121 + p122) * EF
            data.v @ 18 = (p100 + p101 + p110 + p111 + p200 + p201 + p210 + p211) * CF
            data.v @ 19 = (p101 + p111 + p201 + p211) * EF
            data.v @ 20 = (p101 + p102 + p111 + p112 + p201 + p202 + p211 + p212) * CF
            data.v @ 21 = (p110 + p111 + p210 + p211) * EF
            data.v @ 22 = (28 * (p111 + p211) + 2 * (p101 + p110 + p112 + p121 + p201 + p210 + p212 + p221) + p102 + p120 + p202 + p220 - 3 * (p100 + p122 + p200 + p222)) * FF
            data.v @ 23 = (p111 + p112 + p211 + p212) * EF
            data.v @ 24 = (p110 + p111 + p120 + p121 + p210 + p211 + p220 + p221) * CF
            data.v @ 25 = (p111 + p121 + p211 + p221) * EF
            data.v @ 26 = (p111 + p112 + p121 + p122 + p211 + p212 + p221 + p222) * CF
        else
            inline get (x y z)
                ofs := ((vec3 x y z) * r)
                (mapf (coord + ofs)) / (d * PACKING_Q)

            data.v @ 0 = (get -1 -1 -1)
            data.v @ 1 = (get  0 -1 -1)
            data.v @ 2 = (get  1 -1 -1)
            data.v @ 3 = (get -1  0 -1)
            data.v @ 4 = (get  0  0 -1)
            data.v @ 5 = (get  1  0 -1)
            data.v @ 6 = (get -1  1 -1)
            data.v @ 7 = (get  0  1 -1)
            data.v @ 8 = (get  1  1 -1)

            data.v @ 9 = (get -1 -1  0)
            data.v @ 10 = (get  0 -1  0)
            data.v @ 11 = (get  1 -1  0)
            data.v @ 12 = (get -1  0  0)
            data.v @ 13 = (get  0  0  0)
            data.v @ 14 = (get  1  0  0)
            data.v @ 15 = (get -1  1  0)
            data.v @ 16 = (get  0  1  0)
            data.v @ 17 = (get  1  1  0)

            data.v @ 18 = (get -1 -1  1)
            data.v @ 19 = (get  0 -1  1)
            data.v @ 20 = (get  1 -1  1)
            data.v @ 21 = (get -1  0  1)
            data.v @ 22 = (get  0  0  1)
            data.v @ 23 = (get  1  0  1)
            data.v @ 24 = (get -1  1  1)
            data.v @ 25 = (get  0  1  1)
            data.v @ 26 = (get  1  1  1)

    ;

fn voxelize-init ()
    let index = (deref gl_GlobalInvocationID.x)
    subdivide-cell index

fn voxelize ()
    let index = (deref gl_GlobalInvocationID.x)
    if (index < buf-cells-in-info.count)
        subdivide-cell (deref (buf-cells-in.entries @ index))

fn simplify ()
    local_size THREADSIZE 1 1
    let index = (deref gl_GlobalInvocationID.x)
    if (index < buf-cells-in-info.count)
        simplify-cell (deref (buf-cells-in.entries @ index))

fn supershader ()
    local_size THREADSIZE 1 1
    let mode = (deref u-program)
    switch mode
    case ProgramVoxelizeInit
        voxelize-init;
    case ProgramVoxelize
        voxelize;
    #case ProgramSimplify
        simplify;
    default
        ;;

fn calc-projection ()
    let aspect = (vec2 (/ (deref shglobals.aspect)) 1.0)
    'ifp-perspective ProjectionSetup aspect 0.1

inout-geometry geom_data : CubeData
fn rasterize-vert ()
    let index = ((deref gl_VertexID) as u32)
    let data = (deref (buf-vertex-attr1-in.entries @ index))
    geom_data.out = data
    ;

inline transform-rotate (p)
    let a = ((deref shglobals.time) * 0.2)
    let c s = (cos a) (sin a)
    vec3
        c * p.x - s * p.z
        p.y
        s * p.x + c * p.z

inline transform-invert-rotate (p)
    let a = ((deref shglobals.time) * -0.2)
    let c s = (cos a) (sin a)
    vec3
        c * p.x - s * p.z
        p.y
        s * p.x + c * p.z

inline transform-pos (p)
    v := (transform-rotate p)
    vec3 v.xy (v.z + 1.0)

inout depthval : f32
inout ray_origin : vec3
inout ray_dir : vec3
inout cube_data : CubeData flat
fn rasterize-geom ()
    input_primitive points
    output_primitive triangle_strip 14

    let data = (geom_data.in @ 0)

    let key =
        static-if USE_PACKING (deref data.v0.x)
        else (deref data.key)

    let level = (((deref u-level) as u32) - 1)
    let r = (/ (f32 (1:u32 << level)))
    let d = (2.0 * r)
    ucoord := (unpack-morton3x10 key)
    coord := (vec3 ucoord) * d - 1.0

    static-if USE_PACKING
        cube_data.out.v0 = data.v0
        static-if USE_LINEAR_FILTER
        else
            cube_data.out.v1 = data.v1
    else
        cube_data.out.key = data.key
        cube_data.out.v = data.v

    inline write-vertex (i)
        let p = (cube-vertex i)
        p := (vec3 p.x p.y (1 - p.z))
        ray_origin.out = p

        coord := coord + (vec3 p) * d
        coord := (transform-pos coord)

        ray_dir.out =
            transform-invert-rotate coord

        let proj =
            calc-projection;

        let pcoord =
            'project proj
                vec4 coord 1.0

        depthval.out = coord.z
        gl_Position = pcoord
        EmitVertex;

    for i in (range 14)
        write-vertex i
    EndPrimitive;
    ;

fn pack-surfel-data (normal depth color matdata)
    let normal =
        bitcast (packSnorm2x16 (pack_normal_snorm normal)) f32
    let color =
        bitcast (packUnorm4x8 color) f32
    let matdata =
        bitcast (packUnorm4x8 matdata) f32
    vec4 normal matdata color depth

fn unpack-surfel-data (frag)
    let normal =
        unpack_normal_snorm (unpackSnorm2x16 (bitcast frag.x u32))
    let matdata =
        unpackUnorm4x8 (bitcast frag.y u32)
    let color =
        unpackUnorm4x8 (bitcast frag.z u32)
    _
        normal
        frag.w
        color
        matdata

out out_Color : vec4
    binding = 0
fn rasterize-frag ()
    fragment_depth depth_less
    let level = (((deref u-level) as u32) - 1)
    let r = (/ (f32 (1:u32 << level)))
    let d = (2.0 * r)
    let key =
        static-if USE_PACKING (deref cube_data.in.v0.x)
        else (deref cube_data.in.key)
    ucoord := (unpack-morton3x10 key)
    coord := (vec3 ucoord) * d - 1.0

    ro := (deref ray_origin.in)
    rd := (normalize (deref ray_dir.in))

    far := (iCubeFar (ro - 0.5) rd)

    local W :
        static-if USE_LINEAR_FILTER
            array (array (array f32 2) 2) 2
        else
            array (array (array f32 3) 3) 3

    static-if USE_PACKING
        static-if USE_LINEAR_FILTER
            tmp := (unpackSnorm4x8 (deref cube_data.in.v0.y))
            W @ 0 @ 0 @ 0 = tmp.x
            W @ 0 @ 0 @ 1 = tmp.y
            W @ 0 @ 1 @ 0 = tmp.z
            W @ 0 @ 1 @ 1 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v0.z))
            W @ 1 @ 0 @ 0 = tmp.x
            W @ 1 @ 0 @ 1 = tmp.y
            W @ 1 @ 1 @ 0 = tmp.z
            W @ 1 @ 1 @ 1 = tmp.w
        else
            tmp := (unpackSnorm4x8 (deref cube_data.in.v0.y))
            W @ 0 @ 0 @ 0 = tmp.x
            W @ 0 @ 0 @ 1 = tmp.y
            W @ 0 @ 0 @ 2 = tmp.z
            W @ 0 @ 1 @ 0 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v0.z))
            W @ 0 @ 1 @ 1 = tmp.x
            W @ 0 @ 1 @ 2 = tmp.y
            W @ 0 @ 2 @ 0 = tmp.z
            W @ 0 @ 2 @ 1 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v0.w))
            W @ 0 @ 2 @ 2 = tmp.x
            W @ 1 @ 0 @ 0 = tmp.y
            W @ 1 @ 0 @ 1 = tmp.z
            W @ 1 @ 0 @ 2 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v1.x))
            W @ 1 @ 1 @ 0 = tmp.x
            W @ 1 @ 1 @ 1 = tmp.y
            W @ 1 @ 1 @ 2 = tmp.z
            W @ 1 @ 2 @ 0 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v1.y))
            W @ 1 @ 2 @ 1 = tmp.x
            W @ 1 @ 2 @ 2 = tmp.y
            W @ 2 @ 0 @ 0 = tmp.z
            W @ 2 @ 0 @ 1 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v1.z))
            W @ 2 @ 0 @ 2 = tmp.x
            W @ 2 @ 1 @ 0 = tmp.y
            W @ 2 @ 1 @ 1 = tmp.z
            W @ 2 @ 1 @ 2 = tmp.w
            tmp := (unpackSnorm4x8 (deref cube_data.in.v1.w))
            W @ 2 @ 2 @ 0 = tmp.x
            W @ 2 @ 2 @ 1 = tmp.y
            W @ 2 @ 2 @ 2 = tmp.z
    else
        static-if USE_LINEAR_FILTER
            W @ 0 @ 0 @ 0 = cube_data.in.v @ 0
            W @ 0 @ 0 @ 1 = cube_data.in.v @ 1
            W @ 0 @ 1 @ 0 = cube_data.in.v @ 2
            W @ 0 @ 1 @ 1 = cube_data.in.v @ 3
            W @ 1 @ 0 @ 0 = cube_data.in.v @ 4
            W @ 1 @ 0 @ 1 = cube_data.in.v @ 5
            W @ 1 @ 1 @ 0 = cube_data.in.v @ 6
            W @ 1 @ 1 @ 1 = cube_data.in.v @ 7
        else
            W @ 0 @ 0 @ 0 = cube_data.in.v @ 0
            W @ 0 @ 0 @ 1 = cube_data.in.v @ 1
            W @ 0 @ 0 @ 2 = cube_data.in.v @ 2
            W @ 0 @ 1 @ 0 = cube_data.in.v @ 3
            W @ 0 @ 1 @ 1 = cube_data.in.v @ 4
            W @ 0 @ 1 @ 2 = cube_data.in.v @ 5
            W @ 0 @ 2 @ 0 = cube_data.in.v @ 6
            W @ 0 @ 2 @ 1 = cube_data.in.v @ 7
            W @ 0 @ 2 @ 2 = cube_data.in.v @ 8
            W @ 1 @ 0 @ 0 = cube_data.in.v @ 9
            W @ 1 @ 0 @ 1 = cube_data.in.v @ 10
            W @ 1 @ 0 @ 2 = cube_data.in.v @ 11
            W @ 1 @ 1 @ 0 = cube_data.in.v @ 12
            W @ 1 @ 1 @ 1 = cube_data.in.v @ 13
            W @ 1 @ 1 @ 2 = cube_data.in.v @ 14
            W @ 1 @ 2 @ 0 = cube_data.in.v @ 15
            W @ 1 @ 2 @ 1 = cube_data.in.v @ 16
            W @ 1 @ 2 @ 2 = cube_data.in.v @ 17
            W @ 2 @ 0 @ 0 = cube_data.in.v @ 18
            W @ 2 @ 0 @ 1 = cube_data.in.v @ 19
            W @ 2 @ 0 @ 2 = cube_data.in.v @ 20
            W @ 2 @ 1 @ 0 = cube_data.in.v @ 21
            W @ 2 @ 1 @ 1 = cube_data.in.v @ 22
            W @ 2 @ 1 @ 2 = cube_data.in.v @ 23
            W @ 2 @ 2 @ 0 = cube_data.in.v @ 24
            W @ 2 @ 2 @ 1 = cube_data.in.v @ 25
            W @ 2 @ 2 @ 2 = cube_data.in.v @ 26

    fn _interpolate-quad (W p)
        let q p1 p2 n0 n1 n2 = (cube-simplex-bary p)
        let p0 = (ivec3 0)
        let p1 = (p1 * 2)
        let p2 = (p2 * 2)
        let p3 = (ivec3 2)

        inline get_w (p)
            deref (W @ p.z @ p.y @ p.x)

        inline get_mid (p0 p1)
            m := (p0 + p1) // 2
            static-if USE_WEIGHT_BLUR
                get_w m
            else
                let c0 = (get_w p0)
                let c1 = (get_w p1)
                (2.0 * (get_w m)) - 0.5 * (c0 + c1)

        let c =
            vec4
                get_w p0
                get_w p1
                get_w p2
                get_w p3

        let m1 =
            vec3
                get_mid p1 p2
                get_mid p0 p2
                get_mid p0 p1

        let m2 =
            vec3
                get_mid p0 p3
                get_mid p1 p3
                get_mid p2 p3

        _ (eval-quadratic q c m1 m2) q c m1 m2 n0 n1 n2

    fn _interpolate-lin (W p)
        let q p1 p2 n0 n1 n2 = (cube-simplex-bary p)
        inline get_w (p)
            deref (W @ p.z @ p.y @ p.x)

        let c =
            vec4
                get_w (ivec3 0)
                get_w p1
                get_w p2
                get_w (ivec3 1)
        _ (dot q c) q c n0 n1 n2

    inline interpolate (o)
        static-if USE_LINEAR_FILTER
            _interpolate-lin W o
        else
            _interpolate-quad W o

    let t =
        do
            # reconstruct 1D quadratic coefficients from three samples
            c0 := (interpolate ro)
            c1 := (interpolate (ro + rd * (far * 0.5)))
            c2 := (interpolate (ro + rd * far))
            #c0 := (mapf (coord + ro * d))
            #c1 := (mapf (coord + (ro + rd * (far * 0.5)) * d))
            #c2 := (mapf (coord + (ro + rd * far) * d))

            A := 2.0 * (c2 + c0 - 2.0 * c1)
            B := 4.0 * c1 - 3.0 * c0 - c2
            C := c0

            let k =
                #if (far < 0.01)
                    ? ((c0 >= 0.0) & (c1 <= 0.0)) c0 inf
                if ((abs A) < 0.001)
                    -C / B
                else
                    # (-b +- sqrt(b*b - 4.0*a*c)) / 2.0*a
                    k := -0.5 * B / A
                    q := (sqrt (k * k - C / A))
                    q0 := k - q
                    q1 := k + q
                    ? (q0 < 0.0)
                        ? (q1 > q0) q1 inf
                        q0

            if ((k < 0.0) | (k > 1.0))
                discard;
            k * far
        #do
            local t = 0.0
            local count = 0
            for i in (range RAYMARCH_STEPS)
                p := ro + rd * t
                dist := ((interpolate (deref p)) * PACKING_Q)
                count += 1
                if (dist < RAYMARCH_MINDIST)
                    break;
                t += dist
                if (t > far)
                    discard!;

    p := ro + rd * t
    #n :=
        - (sdNormalFast interpolate p 0.01)

    let n =
        static-if USE_LINEAR_FILTER
            let d q c n0 n1 n2 = (interpolate p)
            let w = c
            normal-from-bary
                arrayof vec3 (vec3 n0) (vec3 n1) (vec3 n2)
                w
        else
            let d q c m1 m2 n0 n1 n2 = (interpolate p)
            let w = (eval-quadratic-diff q c m1 m2)
            normal-from-bary
                arrayof vec3 (vec3 n0) (vec3 n1) (vec3 n2)
                w

    #n :=
        #normalmapf coord (r / 4.0)
        - (sdNormalFast interpolate p 0.01)

    #let dist = (matmapf coord)
    #let material =
        dist.material

    coord := coord + p * d
    p := (transform-pos coord)
    n := (transform-rotate n)

    gl_FragDepth = (0.1 / p.z)

    out_Color =
        pack-surfel-data n
            p.z
            do
                #vec4
                    rd * 0.5 + 0.5
                    1
                #material.albedo
                #vec4 (rd * 0.5 + 0.5) 1
                #vec4 ((deref p) * 0.5 + 0.5) 1
                vec4 1
                #vec4 (normhue (count / RAYMARCH_STEPS)) 1
                #vec4
                    +
                        ? (i == 1) (vec3 1 0 0) (vec3 0)
                        ? (i == 2) (vec3 0 1 0) (vec3 0)
                        ? (i == 3) (vec3 0 0 1) (vec3 0)
                        ? (i == 4) (vec3 1 1 1) (vec3 0)
                    1

            do
                #vec4 material.roughness material.metallic 0 0
                vec4 0.5 0 0 0

#
    let level = (((deref u-level) as u32) - 1)
    let r = (/ (f32 (1:u32 << level)))
    let d = (2.0 * r)
    let coord = (deref modelpos.in)

    uv := ((deref gl_FragCoord) . xy) / (vec2 (deref shglobals.size))
    uv := (uv * 2.0 - 1.0) * (vec2 shglobals.aspect 1)

    let rd = (normalize (vec3 uv 1))
    #let rd = (normalize (deref viewpos.in))

    inline fetchmap (p)

        # ivec3 0..2 0..2 0..2 -> vec3 (n-1)*2*r
        (vec3 (p * 2 - 1)) * r

    inline mapavgf (p)
        * 0.125
            +
                mapf (p + (vec3 -r -r -r))
                mapf (p + (vec3  r -r -r))
                mapf (p + (vec3 -r  r -r))
                mapf (p + (vec3  r  r -r))
                mapf (p + (vec3 -r -r  r))
                mapf (p + (vec3  r -r  r))
                mapf (p + (vec3 -r  r  r))
                mapf (p + (vec3  r  r  r))

    #inline mapf (p)
        let pl = (vec4 0 1 0 0)
        #p.z
        let r = ((sin (deref shglobals.time)) * 0.5 + 0.5)
        #(sqrt (dot p p)) - r

        z := (p.z - 1.0) * 0.5
        r := 0.5
        (p.x * p.x + p.y * p.y) / (r * r) - z * z

    let c =
        vec4
            mapavgf (deref (modelcorners.in @ 0))
            mapavgf (deref (modelcorners.in @ 1))
            mapavgf (deref (modelcorners.in @ 2))
            mapavgf (deref (modelcorners.in @ 3))

    #c := c * c * (sign c)

    inline midpoint (v1 v2)
        d := (mapf ((modelcorners.in @ v1 + modelcorners.in @ v2) * 0.5))
        #d := d * d * (sign d)
        #d * 2.0 - ((c @ v1) + (c @ v2)) * 0.5
        d


    let m1 =
        vec3
            midpoint 2 1
            midpoint 0 2
            midpoint 1 0

    let m2 =
        vec3
            midpoint 0 3
            midpoint 1 3
            midpoint 2 3

    let hit near far =
        iQuadricSimplex (deref corners.in)
            #\ (c * c * (sign c)) (m1 * m1 * (sign m1)) (m2 * m2 * (sign m2))
            \ c m1 m2
            #vec4 2
            #vec3 -1
            #vec3 -1
            vec3 0
            rd

    if (not hit)
        discard!;

    #corners.in @ 0

    #let coord = (rd *

    coord :=
        +
            modelcorners.in @ 0 * near.b.x
            modelcorners.in @ 1 * near.b.y
            modelcorners.in @ 2 * near.b.z
            modelcorners.in @ 3 * near.b.w

    let dist = (matmapf coord)
    let material =
        dist.material
    let n =
        #normalmapf coord (r / 32.0)
        - near.n

    gl_FragDepth = (0.1 / (rd.z * near.t))

    # rotate it a little
    embed
        let a = ((deref shglobals.time) * 0.2)
        let c s = (cos a) (sin a)

        n :=
            vec3
                c * n.x - s * n.z
                n.y
                s * n.x + c * n.z

    out_Color =
        pack-surfel-data n
            deref depthval.in
            do
                #vec4
                    rd * 0.5 + 0.5
                    1
                #material.albedo
                vec4 1
            do
                #vec4 material.roughness material.metallic 0 0
                vec4 0.5 0 0 0

#uniform img-target-rgba32f : (image2D rgba32f)
    binding = IMAGE_TARGET_RGBA32F
    \ coherent writeonly restrict

uniform u-level : i32
    location = UNIFORM_LEVEL

fn mixdown (uv)
    #let t = (deref shglobals.time)
    let size =
        vec2 (deref shglobals.size)
    let uv2 =
        (uv * 2.0 - 1.0) * (vec2 shglobals.aspect 1)
    let uv = (ivec2 ((deref gl_FragCoord) . xy + 0.5))

    let col =
        texelFetch smp-screen uv 0
    let normal depth color matdata = (unpack-surfel-data col)
    if (depth == 0.0)
        return
            vec4 0.1 0.1 0.2 1
    let proj =
        calc-projection;
    let coord =
        vec3 ((uv2 * 2.0 - 1.0) * depth / proj.aspect) depth
    let rd = (normalize coord)

    let l =
        normalize
            vec3 0.5 -1.0 0.25
    let lambert =
        max 0.0 (dot normal l)

    let albedo = color.rgb
    let ambient =
        ((dot normal (vec3 0.0 -1.0 0.0)) * 0.5 + 0.5) * 0.1
    let exposure = 2.0

    let roughness = matdata.x
    let metallic = matdata.y
    let color =
        linear->sRGB
            tonemap
                * exposure
                    +
                        ambient * albedo * (1.0 - metallic)
                        * lambert
                            BRDF albedo
                                roughness
                                metallic
                                \ l rd normal

    return
        vec4 color 1.0
        #vec4
            #\ uv 0.0
            #normal * 0.5 + 0.5
            vec3
                (dot normal (normalize (vec3 0 -1 0))) * 0.5 + 0.5
            #normhue depth
            #normhue (radius / 16.0)
            #normhue (w / 8.0)
            1.0

fn visualize-buffer (uv)
    #let t = (deref shglobals.time)
    let size =
        vec2 (deref shglobals.size)
    let uv2 =
        (uv * 2.0 - 1.0) * (vec2 shglobals.aspect 1)
    let uv = (ivec2 ((deref gl_FragCoord) . xy + 0.5))

    let col =
        texelFetch smp-screen uv 0
    let normal depth color matdata = (unpack-surfel-data col)
    if (depth == 0.0)
        return
            vec4 0 0 0 1

    return
        vec4
            normal * -0.5 + 0.5
            #normhue (depth / 8.0)
            #normhue (radius / 16.0)
            #color.xyz
            1.0

fn shader (uv)
    #mixdown uv
    visualize-buffer uv

inline main ()

    # pass overview:
        in: compute 4 * 4 * 4
        per thread:
            traverse 1/64th of octree
        for each leaf found:
            increase atomic counter in indirect draw call argument to obtain index
            append position + normal as vec4 (xyz, packed normal)
            append color as i32
                gamma compressed RGB10 values
                values >= 256 are emissive
                2 bits left for ?
            append material props as i32
                * roughness
                * metallic
                * film thickness
                * waxiness?
                * hue rotation?
                * UV activeness?
                * snowy glitter?

        in: indirect draw call argument
        out: rasterized voxel cubes

    let NUM_CMD_BUFFERS = 1

    global compute_cmd_buffers = (GL.CreateBuffer)
    setup-ssbo compute_cmd_buffers buf-compute-cmd NUM_CMD_BUFFERS

    global draw_cmd_buffers = (GL.CreateBuffer)
    setup-ssbo draw_cmd_buffers buf-draw-cmd NUM_CMD_BUFFERS

    let NUM_BUFFERS = 2

    global cell_info_buffers =
        arrayof GL.uint
            GL.CreateBuffer;
            GL.CreateBuffer;

    global cell_buffers =
        arrayof GL.uint
            GL.CreateBuffer;
            GL.CreateBuffer;
    let cell_info_buffer_sz = (sizeof u32)
    let cell_buffer_sz = ((sizeof u32) * MAX_VOXELS)
    for i in (range (NUM_BUFFERS as u32))
        let buf = (cell_info_buffers @ i)
        GL.NamedBufferData buf (i32 cell_info_buffer_sz) null GL.STREAM_COPY
        GL.BindBufferRange GL.SHADER_STORAGE_BUFFER (BINDING_BUF_CELLS_IN_INFO + i)
            \ buf 0:i64 (i64 cell_info_buffer_sz)
        let buf = (cell_buffers @ i)
        GL.NamedBufferData buf (i32 cell_buffer_sz) null GL.STREAM_COPY
        GL.BindBufferRange GL.SHADER_STORAGE_BUFFER (BINDING_BUF_CELLS_IN + i)
            \ buf 0:i64 (i64 cell_buffer_sz)

    global vertex_buffer = (GL.CreateBuffer)
    let vertex_buffer_sz = ((sizeof CubeData) * MAX_VOXELS)
    GL.NamedBufferData vertex_buffer (i32 vertex_buffer_sz) null GL.STREAM_COPY

    global fb-scene-color = (GL.CreateTexture GL.TEXTURE_2D)
    'setup fb-scene-color
        size = (ivec2 2048 2048)
        format = GL.RGBA32F
    do
        let h = 2048
        GL.ClearTexImage fb-scene-color 0 GL.RGBA GL.FLOAT null

    global rb-scene-depth = (GL.CreateRenderbuffer)
    setup-renderbuffer rb-scene-depth 2048 2048
        format = GL.DEPTH_COMPONENT
    global fb-scene = (GL.CreateFramebuffer)
    setup-framebuffer fb-scene
        color = fb-scene-color
        rb-depth = rb-scene-depth

    global vao-empty = (GL.CreateVertexArray)

    global pg-rasterize = (GL.CreateProgram)
    call
        attach-shaders (deref pg-rasterize)
            vertex = rasterize-vert
            geometry = rasterize-geom
            fragment = rasterize-frag
            #debug = true

    global pg-supershader = (GL.CreateProgram)
    call
        attach-shaders (deref pg-supershader)
            compute = supershader

    global pg-simplify = (GL.CreateProgram)
    call
        attach-shaders (deref pg-simplify)
            compute = simplify
            #debug = true

    global pg-setup-compute = (GL.CreateProgram)
    call
        attach-shaders (deref pg-setup-compute)
            compute = setup-compute-command
            #debug = true

    global pg-setup-draw = (GL.CreateProgram)
    call
        attach-shaders (deref pg-setup-draw)
            compute = setup-draw-arrays-command
            #debug = true

    inline per-frame-setup (size pg-test frame)

        GL.BindTextureUnit 0 fb-scene-color
        GL.Uniform smp-screen 0

        inline bind-read-buffer (i)
            GL.BindBufferRange GL.SHADER_STORAGE_BUFFER
                BINDING_BUF_CELLS_IN
                cell_buffers @ i
                \ 0:i64 (i64 cell_buffer_sz)
            GL.BindBufferRange GL.SHADER_STORAGE_BUFFER
                BINDING_BUF_CELLS_IN_INFO
                cell_info_buffers @ i
                \ 0:i64 (i64 cell_info_buffer_sz)

        inline clear-buffer-count (i)
            let buf = (cell_info_buffers @ i)
            let ptr =
                GL.MapNamedBufferRange buf 0 (sizeof u32)
                    | GL.MAP_WRITE_BIT
                        GL.MAP_INVALIDATE_BUFFER_BIT
                        #GL.MAP_UNSYNCHRONIZED_BIT
            let ptr = (bitcast ptr (mutable pointer CellValsInfo))
            ptr.count = 0:u32
            GL.UnmapNamedBuffer buf

        inline bind-write-buffer (i)
            clear-buffer-count i
            GL.BindBufferRange GL.SHADER_STORAGE_BUFFER
                BINDING_BUF_CELLS_OUT
                cell_buffers @ i
                \ 0:i64 (i64 cell_buffer_sz)
            GL.BindBufferRange GL.SHADER_STORAGE_BUFFER
                BINDING_BUF_CELLS_OUT_INFO
                cell_info_buffers @ i
                \ 0:i64 (i64 cell_info_buffer_sz)

        GL.UseProgram pg-supershader
        GL.BindBuffer GL.DISPATCH_INDIRECT_BUFFER compute_cmd_buffers

        local idx = 0
        local level = 0
        inline print-in-count (i)
            let buf = (cell_info_buffers @ i)
            let ptr =
                GL.MapNamedBufferRange buf 0 (sizeof u32)
                    GL.MAP_READ_BIT
            let ptr = (bitcast ptr (pointer CellValsInfo))
            print ptr.count
            GL.UnmapNamedBuffer buf

        inline init-voxels (l)
            level = l
            let i0 = (deref idx)
            idx = ((idx + 1) & 1)
            let i1 = (deref idx)
            let level = (deref level)
            GL.Uniform u-program ProgramVoxelizeInit
            GL.Uniform u-level level
            bind-read-buffer i0
            bind-write-buffer i1
            GL.DispatchCompute ((((1 << level) ** 3) // THREADSIZE) as u32) 1 1
            GL.MemoryBarrier GL.SHADER_STORAGE_BARRIER_BIT

        inline refine-voxels ()
            let i0 = (deref idx)
            idx = ((idx + 1) & 1)
            let i1 = (deref idx)
            level = level + 1
            let level = (deref level)
            GL.UseProgram pg-setup-compute
            GL.Uniform u-divisor THREADSIZE
            bind-read-buffer i0
            bind-ssbo compute_cmd_buffers buf-compute-cmd none 0
            GL.DispatchCompute 1 1 1
            GL.MemoryBarrier GL.COMMAND_BARRIER_BIT

            GL.UseProgram pg-supershader
            GL.Uniform u-program ProgramVoxelize
            GL.Uniform u-level level
            bind-read-buffer i0
            bind-write-buffer i1
            GL.DispatchComputeIndirect 0
            GL.MemoryBarrier GL.SHADER_STORAGE_BARRIER_BIT

        inline finalize-voxels ()
            let i0 = (deref idx)
            idx = ((idx + 1) & 1)
            let i1 = (deref idx)
            level = level + 1
            let level = (deref level)
            GL.UseProgram pg-setup-compute
            GL.Uniform u-divisor THREADSIZE
            #GL.Uniform u-divisor THREADSIZE
            bind-read-buffer i0
            bind-ssbo compute_cmd_buffers buf-compute-cmd none 0
            GL.DispatchCompute 1 1 1
            GL.MemoryBarrier GL.COMMAND_BARRIER_BIT

            GL.UseProgram pg-simplify
            #GL.Uniform u-program ProgramSimplify
            GL.Uniform u-level level
            bind-read-buffer i0
            bind-write-buffer i1
            GL.BindBufferRange GL.SHADER_STORAGE_BUFFER BINDING_BUF_VERTEX_ATTR1_OUT
                    \ vertex_buffer 0:i64 (i64 vertex_buffer_sz)
            GL.DispatchComputeIndirect 0
            GL.MemoryBarrier GL.SHADER_STORAGE_BARRIER_BIT

        inline draw-surface ()
            #print-in-count (deref idx)
            GL.MemoryBarrier (GL.ALL_BARRIER_BITS as u32)
            GL.BindBuffer GL.DRAW_INDIRECT_BUFFER draw_cmd_buffers
            GL.UseProgram pg-setup-draw
            bind-read-buffer (deref idx)
            bind-ssbo draw_cmd_buffers buf-draw-cmd none 0
            GL.DispatchCompute 1 1 1
            GL.MemoryBarrier GL.COMMAND_BARRIER_BIT
            do
                GL.BindFramebuffer GL.FRAMEBUFFER fb-scene
                GL.Viewport 0 0 (i32 size.x) (i32 size.y)
                GL.ClearColor 0 0 0 0
                GL.DepthFunc GL.GREATER
                GL.ClearDepthf 0
                GL.DepthRangef -1 1
                GL.Enable GL.CULL_FACE
                GL.CullFace GL.BACK
                GL.Enable GL.DEPTH_TEST
                GL.Clear
                    |
                        GL.COLOR_BUFFER_BIT
                        GL.DEPTH_BUFFER_BIT
                        GL.STENCIL_BUFFER_BIT

                GL.UseProgram pg-rasterize
                bind-read-buffer (deref idx)
                GL.BindBufferRange GL.SHADER_STORAGE_BUFFER BINDING_BUF_VERTEX_ATTR1_IN
                        \ vertex_buffer 0:i64 (i64 vertex_buffer_sz)
                GL.Uniform u-level (deref level)
                GL.BindVertexArray vao-empty
                GL.DrawArraysIndirect GL.POINTS null

                GL.Disable GL.BLEND
                GL.Disable GL.DEPTH_TEST
                GL.Disable GL.CULL_FACE
                GL.BindFramebuffer GL.FRAMEBUFFER 0

        init-voxels 5
        refine-voxels;
        #refine-voxels;
        #refine-voxels;
        finalize-voxels;
        draw-surface;

    _ per-frame-setup shader

fn program ()
    render-fragment-shader main
        #debug = true
        size = (ivec2 512)


static-if true
    program;
else
    define f
        compile
            typify program
            'O3

    f;