Raytracing с треугольной сеткой в ​​Webgl 2.0 с данными текстуры

Question

Я хочу сделать raytracer с треугольными сетками в webgl2.Я задал другой вопрос, и я получил пример кода, чтобы сделать это.

Чтобы получить доступ в шейдере ко всем треугольникам и выполнить пересечение лучей с треугольниками, данные сетки должны быть сохранены в текстуре.это код, который я немного изменил:

(() => {
'use strict';
// vertex
const vs = `#version 300 es\n
in vec2 p;
out vec2 vuv;
void main(){
    gl_Position = vec4(vuv = p, 0, 2);
}`;

// fragment
const fs = `#version 300 es\n
precision highp float;
precision highp int;
precision highp sampler2D; 
in vec2 vuv;
uniform float time;
uniform vec2 Res, mouse;
uniform sampler2D uMeshData;
uniform int vertsCount;
layout(location = 0) out lowp vec4 fragColor;

struct Ray {
  vec3 orig, dir;
}R_;

mat4 rotate() {
    float x = mouse.x, y=mouse.y+sin(time*2.),z=0.;
    float a = sin(x), b = cos(x), c = sin(y), d = cos(y), e = sin(z), f = cos(z), ac = a * c, bc = b * c;

    return mat4(d * f,           d * e,           -c,     0.0, 
                ac * f - b * e,  ac * e + b * f,  a * d,  0.0,     
                bc * f + a * e,  bc * e - a * f,  b * d,  0.0, 
                0.0,             0.0,             0.0,    1.0);
}

// https://github.com/Jojendersie/gpugi/blob/5d18526c864bbf09baca02bfab6bcec97b7e1210/gpugi/shader/intersectiontests.glsl#L63
bool isTriangle(Ray ray, in vec3 p0, in vec3 p1, in vec3 p2, out vec3 N) {
  vec3 e0 = p1 - p0, e1 = p0 - p2;
  N = cross(e1, e0);
  vec3 e2 = (1.0 / dot(N, ray.dir)) * (p0 - ray.orig);
  vec3 i = cross(ray.dir, e2);
  vec3 b = vec3(0.0, dot(i, e1), dot(i, e0));
  b.x = 1.0 - (b.z + b.y);
  return (dot(N, e2) > 1e-8) && all(greaterThanEqual(b, vec3(0.0)));
}

void Camera(out Ray ray, vec3 lookAt, vec3 up, float angle, float aspect) {
  vec3 g = normalize(lookAt - ray.orig);
  vec3 u = normalize(cross(g, up));
  vec3 v = normalize(cross(u, g));
  u = u * tan(radians(angle * .5));
  v = v * tan(radians(angle * .5)) / aspect;
  ray.dir = normalize(g + ray.dir.x * u + ray.dir.y * v);
}

void main() {
  vec3 SceneCol = vec3(0.5);

  vec3 hit = vec3(0.);
  vec4 a = vec4(0.0), b = vec4(0.0), c = vec4(0.0);

  R_ = Ray(vec3(0.0, 0.0, 3.0), vec3(vuv, -1.));

  Camera(R_, vec3(0., 0., 1.), vec3(0., 1., 0.), 90.0, (Res.x / Res.y));

  float mindist = -1000.0;

    // here comes this importend part unpack the texture
  for (int i = 0; i < vertsCount; i += 3) 
  {

    a = rotate() * texelFetch(uMeshData, ivec2(i, 0), 0);
    b = rotate() * texelFetchOffset(uMeshData, ivec2(i, 0), 0, ivec2(1, 0));
    c = rotate() * texelFetchOffset(uMeshData, ivec2(i, 0), 0, ivec2(2, 0));

    if (isTriangle(R_, a.xyz, b.xyz, c.xyz, hit))
    {
      float z = hit.z;
      if (z > mindist) {
        mindist = z;
        SceneCol.rgb = vec3(hit.x, hit.y, 1. - (hit.x - hit.y));
      };
    }
  }

  vec3 sky = vec3(0.5, 0.25, 0.1) * (-R_.dir.y - 0.1);
  fragColor.rgb = SceneCol + sky;
  fragColor.a = 1.0;
}`;

    const canvas = document.getElementById('c');
    const gl = canvas.getContext('webgl2', {
        alpha: !1,
        depth: !1,
        stencil: !1,
        antialias: !1,
        premultipliedAlpha: !1,
        presereDrawingBuffer: !1,
        failIfMajorPerformanceCaveat: !1
    });

    const { width, height } = canvas.getBoundingClientRect();
    console.log(width, height)
    gl.canvas.width =  width; //window.innerWidth;
    gl.canvas.height =  height; //window.innerHeight;

    // init
    const P = gl.createProgram();

    const Fp = gl.createShader(gl.FRAGMENT_SHADER);
    gl.shaderSource(Fp, fs);
    gl.compileShader(Fp);
    if (!gl.getShaderParameter(Fp, gl.COMPILE_STATUS)) throw '! F r a g: ' + gl.getShaderInfoLog(Fp);
    gl.attachShader(P, Fp);

    const Vp = gl.createShader(gl.VERTEX_SHADER);
    gl.shaderSource(Vp, vs);
    gl.compileShader(Vp);
    if (!gl.getShaderParameter(Vp, gl.COMPILE_STATUS)) throw '! V e r t: ' + gl.getShaderInfoLog(Vp);
    gl.attachShader(P, Vp);

    // link use program
    gl.linkProgram(P);
    gl.useProgram(P);

    // uniform location
    const time_loc = gl.getUniformLocation(P, 'time');
    const res_loc = gl.getUniformLocation(P, 'Res');
    const uLvertices = gl.getUniformLocation(P, 'vertsCount');
    const uLSr = gl.getUniformLocation(P, 'uMeshData');
    const mouse_loc = gl.getUniformLocation(P, 'mouse');

    // free resources
    gl.detachShader(P, Fp);
    gl.detachShader(P, Vp);
    gl.deleteProgram(P);

    // fullscreen quad
    gl.bindBuffer(gl.ARRAY_BUFFER, gl.createBuffer());
    gl.bufferData(gl.ARRAY_BUFFER, new Int8Array([-4, 2, 2, -4, 2, 2, -4, 2, -4, -4, 2, -4 ]), gl.STATIC_DRAW);
    gl.enableVertexAttribArray(0);
    gl.vertexAttribPointer(0, 2, gl.BYTE, !1, 0, 0);
    gl.bindVertexArray(null);

    // bind texture
    const texture = gl.createTexture();
    gl.bindTexture(gl.TEXTURE_2D, texture);


    // blender 2.79 Icosphere
    // export -> *.raw (needs to be enable first under settings)
    const verts = [
        0.000000, 0.000000, -1.000000, 0.425323, -0.309011, -0.850654, -0.162456, -0.499995, -0.850654,
        0.723607, -0.525725, -0.447220, 0.425323, -0.309011, -0.850654, 0.850648, 0.000000, -0.525736,
        0.000000, 0.000000, -1.000000, -0.162456, -0.499995, -0.850654, -0.525730, 0.000000, -0.850652,
        0.000000, 0.000000, -1.000000, -0.525730, 0.000000, -0.850652, -0.162456, 0.499995, -0.850654,
        0.000000, 0.000000, -1.000000, -0.162456, 0.499995, -0.850654, 0.425323, 0.309011, -0.850654,
        0.723607, -0.525725, -0.447220, 0.850648, 0.000000, -0.525736, 0.951058, -0.309013, 0.000000,
        -0.276388, -0.850649, -0.447220, 0.262869, -0.809012, -0.525738, 0.000000, -1.000000, 0.000000,
        -0.894426, 0.000000, -0.447216, -0.688189, -0.499997, -0.525736, -0.951058, -0.309013, 0.000000,
        -0.276388, 0.850649, -0.447220, -0.688189, 0.499997, -0.525736, -0.587786, 0.809017, 0.000000,
        0.723607, 0.525725, -0.447220, 0.262869, 0.809012, -0.525738, 0.587786, 0.809017, 0.000000,
        0.723607, -0.525725, -0.447220, 0.951058, -0.309013, 0.000000, 0.587786, -0.809017, 0.000000,
        -0.276388, -0.850649, -0.447220, 0.000000, -1.000000, 0.000000, -0.587786, -0.809017, 0.000000,
        -0.894426, 0.000000, -0.447216, -0.951058, -0.309013, 0.000000, -0.951058, 0.309013, 0.000000,
        -0.276388, 0.850649, -0.447220, -0.587786, 0.809017, 0.000000, 0.000000, 1.000000, 0.000000,
        0.723607, 0.525725, -0.447220, 0.587786, 0.809017, 0.000000, 0.951058, 0.309013, 0.000000,
        0.276388, -0.850649, 0.447220, 0.688189, -0.499997, 0.525736, 0.162456, -0.499995, 0.850654,
        -0.723607, -0.525725, 0.447220, -0.262869, -0.809012, 0.525738, -0.425323, -0.309011, 0.850654,
        -0.723607, 0.525725, 0.447220, -0.850648, 0.000000, 0.525736, -0.425323, 0.309011, 0.850654,
        0.276388, 0.850649, 0.447220, -0.262869, 0.809012, 0.525738, 0.162456, 0.499995, 0.850654,
        0.894426, 0.000000, 0.447216, 0.688189, 0.499997, 0.525736, 0.525730, 0.000000, 0.850652,
        0.525730, 0.000000, 0.850652, 0.162456, 0.499995, 0.850654, 0.000000, 0.000000, 1.000000,
        0.525730, 0.000000, 0.850652, 0.688189, 0.499997, 0.525736, 0.162456, 0.499995, 0.850654,
        0.688189, 0.499997, 0.525736, 0.276388, 0.850649, 0.447220, 0.162456, 0.499995, 0.850654,
        0.162456, 0.499995, 0.850654, -0.425323, 0.309011, 0.850654, 0.000000, 0.000000, 1.000000,
        0.162456, 0.499995, 0.850654, -0.262869, 0.809012, 0.525738, -0.425323, 0.309011, 0.850654,
        -0.262869, 0.809012, 0.525738, -0.723607, 0.525725, 0.447220, -0.425323, 0.309011, 0.850654,
        -0.425323, 0.309011, 0.850654, -0.425323, -0.309011, 0.850654, 0.000000, 0.000000, 1.000000,
        -0.425323, 0.309011, 0.850654, -0.850648, 0.000000, 0.525736, -0.425323, -0.309011, 0.850654,
        -0.850648, 0.000000, 0.525736, -0.723607, -0.525725, 0.447220, -0.425323, -0.309011, 0.850654,
        -0.425323, -0.309011, 0.850654, 0.162456, -0.499995, 0.850654, 0.000000, 0.000000, 1.000000,
        -0.425323, -0.309011, 0.850654, -0.262869, -0.809012, 0.525738, 0.162456, -0.499995, 0.850654,
        -0.262869, -0.809012, 0.525738, 0.276388, -0.850649, 0.447220, 0.162456, -0.499995, 0.850654,
        0.162456, -0.499995, 0.850654, 0.525730, 0.000000, 0.850652, 0.000000, 0.000000, 1.000000,
        0.162456, -0.499995, 0.850654, 0.688189, -0.499997, 0.525736, 0.525730, 0.000000, 0.850652,
        0.688189, -0.499997, 0.525736, 0.894426, 0.000000, 0.447216, 0.525730, 0.000000, 0.850652,
        0.951058, 0.309013, 0.000000, 0.688189, 0.499997, 0.525736, 0.894426, 0.000000, 0.447216,
        0.951058, 0.309013, 0.000000, 0.587786, 0.809017, 0.000000, 0.688189, 0.499997, 0.525736,
        0.587786, 0.809017, 0.000000, 0.276388, 0.850649, 0.447220, 0.688189, 0.499997, 0.525736,
        0.000000, 1.000000, 0.000000, -0.262869, 0.809012, 0.525738, 0.276388, 0.850649, 0.447220,
        0.000000, 1.000000, 0.000000, -0.587786, 0.809017, 0.000000, -0.262869, 0.809012, 0.525738,
        -0.587786, 0.809017, 0.000000, -0.723607, 0.525725, 0.447220, -0.262869, 0.809012, 0.525738,
        -0.951058, 0.309013, 0.000000, -0.850648, 0.000000, 0.525736, -0.723607, 0.525725, 0.447220,
        -0.951058, 0.309013, 0.000000, -0.951058, -0.309013, 0.000000, -0.850648, 0.000000, 0.525736,
        -0.951058, -0.309013, 0.000000, -0.723607, -0.525725, 0.447220, -0.850648, 0.000000, 0.525736,
        -0.587786, -0.809017, 0.000000, -0.262869, -0.809012, 0.525738, -0.723607, -0.525725, 0.447220,
        -0.587786, -0.809017, 0.000000, 0.000000, -1.000000, 0.000000, -0.262869, -0.809012, 0.525738,
        0.000000, -1.000000, 0.000000, 0.276388, -0.850649, 0.447220, -0.262869, -0.809012, 0.525738,
        0.587786, -0.809017, 0.000000, 0.688189, -0.499997, 0.525736, 0.276388, -0.850649, 0.447220,
        0.587786, -0.809017, 0.000000, 0.951058, -0.309013, 0.000000, 0.688189, -0.499997, 0.525736,
        0.951058, -0.309013, 0.000000, 0.894426, 0.000000, 0.447216, 0.688189, -0.499997, 0.525736,
        0.587786, 0.809017, 0.000000, 0.000000, 1.000000, 0.000000, 0.276388, 0.850649, 0.447220,
        0.587786, 0.809017, 0.000000, 0.262869, 0.809012, -0.525738, 0.000000, 1.000000, 0.000000,
        0.262869, 0.809012, -0.525738, -0.276388, 0.850649, -0.447220, 0.000000, 1.000000, 0.000000,
        -0.587786, 0.809017, 0.000000, -0.951058, 0.309013, 0.000000, -0.723607, 0.525725, 0.447220,
        -0.587786, 0.809017, 0.000000, -0.688189, 0.499997, -0.525736, -0.951058, 0.309013, 0.000000,
        -0.688189, 0.499997, -0.525736, -0.894426, 0.000000, -0.447216, -0.951058, 0.309013, 0.000000,
        -0.951058, -0.309013, 0.000000, -0.587786, -0.809017, 0.000000, -0.723607, -0.525725, 0.447220,
        -0.951058, -0.309013, 0.000000, -0.688189, -0.499997, -0.525736, -0.587786, -0.809017, 0.000000,
        -0.688189, -0.499997, -0.525736, -0.276388, -0.850649, -0.447220, -0.587786, -0.809017, 0.000000,
        0.000000, -1.000000, 0.000000, 0.587786, -0.809017, 0.000000, 0.276388, -0.850649, 0.447220,
        0.000000, -1.000000, 0.000000, 0.262869, -0.809012, -0.525738, 0.587786, -0.809017, 0.000000,
        0.262869, -0.809012, -0.525738, 0.723607, -0.525725, -0.447220, 0.587786, -0.809017, 0.000000,
        0.951058, -0.309013, 0.000000, 0.951058, 0.309013, 0.000000, 0.894426, 0.000000, 0.447216,
        0.951058, -0.309013, 0.000000, 0.850648, 0.000000, -0.525736, 0.951058, 0.309013, 0.000000,
        0.850648, 0.000000, -0.525736, 0.723607, 0.525725, -0.447220, 0.951058, 0.309013, 0.000000,
        0.425323, 0.309011, -0.850654, 0.262869, 0.809012, -0.525738, 0.723607, 0.525725, -0.447220,
        0.425323, 0.309011, -0.850654, -0.162456, 0.499995, -0.850654, 0.262869, 0.809012, -0.525738,
        -0.162456, 0.499995, -0.850654, -0.276388, 0.850649, -0.447220, 0.262869, 0.809012, -0.525738,
        -0.162456, 0.499995, -0.850654, -0.688189, 0.499997, -0.525736, -0.276388, 0.850649, -0.447220,
        -0.162456, 0.499995, -0.850654, -0.525730, 0.000000, -0.850652, -0.688189, 0.499997, -0.525736,
        -0.525730, 0.000000, -0.850652, -0.894426, 0.000000, -0.447216, -0.688189, 0.499997, -0.525736,
        -0.525730, 0.000000, -0.850652, -0.688189, -0.499997, -0.525736, -0.894426, 0.000000, -0.447216,
        -0.525730, 0.000000, -0.850652, -0.162456, -0.499995, -0.850654, -0.688189, -0.499997, -0.525736,
        -0.162456, -0.499995, -0.850654, -0.276388, -0.850649, -0.447220, -0.688189, -0.499997, -0.525736,
        0.850648, 0.000000, -0.525736, 0.425323, 0.309011, -0.850654, 0.723607, 0.525725, -0.447220,
        0.850648, 0.000000, -0.525736, 0.425323, -0.309011, -0.850654, 0.425323, 0.309011, -0.850654,
        0.425323, -0.309011, -0.850654, 0.000000, 0.000000, -1.000000, 0.425323, 0.309011, -0.850654,
        -0.162456, -0.499995, -0.850654, 0.262869, -0.809012, -0.525738, -0.276388, -0.850649, -0.447220,
        -0.162456, -0.499995, -0.850654, 0.425323, -0.309011, -0.850654, 0.262869, -0.809012, -0.525738,
        0.425323, -0.309011, -0.850654, 0.723607, -0.525725, -0.447220, 0.262869, -0.809012, -0.525738,
    ];


    const meshVerts = new Float32Array(verts);
    const vertsLenght = meshVerts.length / 3;
    gl.uniform1i(uLvertices, vertsLenght);
    gl.pixelStorei(gl.UNPACK_ALIGNMENT, 1);
    gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGB32F, vertsLenght, 1, 0, gl.RGB, gl.FLOAT, meshVerts);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);

    // mouse click
    let mousePosition = [0, 0];
    gl.canvas.addEventListener('mousemove', (e) => {
        if (!e.buttons) return;
        if (e.buttons == 1) mousePosition = [e.clientX * .01, e.clientY * .01];
    }, !1);

    // animation
    const draw = (clock) => {
        clock *= 0.001;
        gl.viewport(0.0, 0.0, gl.drawingBufferWidth, gl.drawingBufferHeight);
        gl.activeTexture(gl.TEXTURE0);
        gl.bindTexture(gl.TEXTURE_2D, texture);
        gl.uniform1i(uLSr, 0);
        gl.uniform1f(time_loc, clock);
        gl.uniform2f(mouse_loc, mousePosition[0], mousePosition[1]);
        gl.uniform2f(res_loc, width, height);
        gl.drawArrays(gl.TRIANGLE_STRIP, 0, 6);
        requestAnimationFrame(draw);
    };
    requestAnimationFrame(draw);
})()

и HTML-файл:

 <!DOCTYPE html>
    <html>
    <head>
        <title></title>
    </head>
    <body>
         <canvas id="c"></canvas>
         <script type="text/javascript" src="main.js"></script>
    </body>
    </html>

Мой вопрос: как я могу изменить этот код, чтобы добавить другой объект?Нужно ли мне добавлять все экспорты из blender в переменную verts и загружать их в шейдер?как я видел, экспорт блендера хранит информацию о положении объектов.

А как насчет света?Как я могу сделать 2 прохода рендеринга, который вы сначала вычислите геометрию, а затем огни?я видел это из kronos https://github.com/tsherif/webgl2examples/blob/master/deferred.html, но я многого не могу понять.

Моя цель - сделать этот двухпроходный рендеринг с использованием объектных сеток (по мере экспорта блендера)