Update 7 files

- /book/features/adding_basic_HTML_elements.md
- /book/features/creating_basic_HTML_elements.md
- /book/features/adding_HTML_elements.md
- /book/_toc.yml
- /book/_static/element_render_box.html
- /book/_static/bimodal_field.mtl
- /book/_static/bimodal_field.obj

book/_static/bimodal_field.mtl

@@ -0,0 +1,52 @@
+# Blender 4.0.2 MTL File: 'bimodal_distribution_v06_to_obj.blend'
+# www.blender.org
+
+newmtl bedrock_dark
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+
+newmtl grass_flat
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.261166 0.800000 0.226093
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+
+newmtl gravel
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.155926 0.127438 0.088656
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+
+newmtl soil
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.372228 0.272421 0.169322
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+
+newmtl water
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.026867 0.549270 0.800000
+Ks 1.000000 1.000000 1.000000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 0.500000
+illum 2

book/_static/element_render_box.html

@@ -0,0 +1,155 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Subsurface</title>
+  <style>
+    html, body {
+      margin: 0;
+      height: 100%;
+    }
+    #c {
+      width: 100%;
+      height: 100%;
+      display: block;
+    }
+  </style>
+</head>
+<body>
+  <canvas id="c"></canvas>
+
+  <script type="module">
+  
+  	// Path to object
+    var path_obj = "bimodal_field.obj";
+    var path_mtl = "bimodal_field.mtl";
+  
+  
+    // Three.js - Load .OBJ and .MTL file - Windmill2
+    // from https://threejsfundamentals.org/threejs/threejs-load-obj-materials-windmill2.html
+
+    import * as THREE from 'https://threejsfundamentals.org/threejs/resources/threejs/r127/build/three.module.js';
+    import { OrbitControls } from 'https://threejsfundamentals.org/threejs/resources/threejs/r127/examples/jsm/controls/OrbitControls.js';
+    import { OBJLoader } from 'https://threejsfundamentals.org/threejs/resources/threejs/r127/examples/jsm/loaders/OBJLoader.js';
+    import { MTLLoader } from 'https://threejsfundamentals.org/threejs/resources/threejs/r127/examples/jsm/loaders/MTLLoader.js';
+
+    function main() {
+      const canvas = document.querySelector('#c');
+      const renderer = new THREE.WebGLRenderer({ canvas });
+
+      const fov = 45;
+      const aspect = 2; // the canvas default
+      const near = 0.1;
+      const far = 100;
+      const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
+      camera.position.set(0, 10, 20);
+
+      const controls = new OrbitControls(camera, canvas);
+      controls.target.set(0, 5, 0);
+      controls.update();
+
+      const scene = new THREE.Scene();
+      scene.background = new THREE.Color('white');
+
+      {
+        const skyColor = 0xB1E1FF; // light blue
+        const groundColor = 0xB97A20; // brownish orange
+        const intensity = 1;
+        const light = new THREE.HemisphereLight(skyColor, groundColor, intensity);
+        scene.add(light);
+      }
+
+      {
+        const color = 0xFFFFFF;
+        const intensity = 1;
+        const light = new THREE.DirectionalLight(color, intensity);
+        light.position.set(5, 10, 2);
+        scene.add(light);
+        scene.add(light.target);
+      }
+
+      function frameArea(sizeToFitOnScreen, boxSize, boxCenter, camera) {
+        const halfSizeToFitOnScreen = sizeToFitOnScreen * 0.5;
+        const halfFovY = THREE.MathUtils.degToRad(camera.fov * .5);
+        const distance = halfSizeToFitOnScreen / Math.tan(halfFovY);
+        // compute a unit vector that points in the direction the camera is now
+        // in the xz plane from the center of the box
+        const direction = (new THREE.Vector3())
+          .subVectors(camera.position, boxCenter)
+          .multiply(new THREE.Vector3(1, 0, 1))
+          .normalize();
+
+        // move the camera to a position distance units way from the center
+        // in whatever direction the camera was from the center already
+        camera.position.copy(direction.multiplyScalar(distance).add(boxCenter));
+
+        // pick some near and far values for the frustum that
+        // will contain the box.
+        camera.near = boxSize / 100;
+        camera.far = boxSize * 100;
+
+        camera.updateProjectionMatrix();
+
+        // point the camera to look at the center of the box
+        camera.lookAt(boxCenter.x, boxCenter.y, boxCenter.z);
+      }
+
+      {
+        const mtlLoader = new MTLLoader();
+        mtlLoader.load(path_mtl, (mtl) => {
+          mtl.preload();
+          const objLoader = new OBJLoader();
+          objLoader.setMaterials(mtl);
+          objLoader.load(path_obj, (root) => {
+            scene.add(root);
+
+            // compute the box that contains all the stuff
+            // from root and below
+            const box = new THREE.Box3().setFromObject(root);
+
+            const boxSize = box.getSize(new THREE.Vector3()).length();
+            const boxCenter = box.getCenter(new THREE.Vector3());
+
+            // set the camera to frame the box
+            frameArea(boxSize * 1.2, boxSize, boxCenter, camera);
+
+            // update the Trackball controls to handle the new size
+            controls.maxDistance = boxSize * 10;
+            controls.target.copy(boxCenter);
+            controls.update();
+          });
+        });
+      }
+
+      function resizeRendererToDisplaySize(renderer) {
+        const canvas = renderer.domElement;
+        const width = canvas.clientWidth;
+        const height = canvas.clientHeight;
+        const needResize = canvas.width !== width || canvas.height !== height;
+        if (needResize) {
+          renderer.setSize(width, height, false);
+        }
+        return needResize;
+      }
+
+      function render() {
+
+        if (resizeRendererToDisplaySize(renderer)) {
+          const canvas = renderer.domElement;
+          camera.aspect = canvas.clientWidth / canvas.clientHeight;
+          camera.updateProjectionMatrix();
+        }
+
+        renderer.render(scene, camera);
+
+        requestAnimationFrame(render);
+      }
+
+      requestAnimationFrame(render);
+    }
+
+    main();
+  </script>
+</body>
+</html>