-const MASS = 0.1;\r
-\r
-class Constraint {\r
- constructor(p1, p2, distance) {\r
- this.p1 = p1;\r
- this.p2 = p2;\r
- this.distance = distance;\r
- }\r
-}\r
-\r
-class Particle {\r
- constructor(x, y, z, mass) {\r
- this.position = new THREE.Vector3(x, y, z);\r
- this.previous = new THREE.Vector3(x, y, z);\r
- this.acceleration = new THREE.Vector3(0, 0, 0);\r
- this.mass = mass;\r
- }\r
- addForce(force) {\r
-\r
- }\r
- verlet(dt) {\r
-\r
- }\r
-}\r
-\r
-class Cloth {\r
- constructor(width, height, numPointsWidth, numPointsHeight) {\r
- this.width = width;\r
- this.height = height;\r
- this.numPointsWidth = numPointsWidth;\r
- this.numPointsHeight = numPointsHeight;\r
-\r
- /**\r
- * distance between two vertices horizontally/vertically\r
- * divide by the number of points minus one\r
- * because there are (n - 1) lines between n vertices\r
- */\r
- let stepWidth = width / (numPointsWidth - 1);\r
- let stepHeight = height / (numPointsHeight - 1);\r
-\r
- /**\r
- * iterate over the number of vertices in x/y axis\r
- * and add a new Particle to "particles"\r
- */\r
- this.particles = [];\r
- for (let y = 0; y < numPointsHeight; y++) {\r
- for (let x = 0; x < numPointsWidth; x++) {\r
- this.particles.push(\r
- new Particle(\r
- (x - ((numPointsWidth-1)/2)) * stepWidth,\r
- height - (y + ((numPointsHeight-1)/2)) * stepHeight,\r
- 0,\r
- MASS)\r
- );\r
- }\r
- }\r
-\r
- const REST_DIST_X = width / (numPointsWidth-1);\r
- const REST_DIST_Y = height / (numPointsHeight-1);\r
-\r
- /**\r
- * generate constraints (springs)\r
- */\r
- this.constraints = [];\r
- for (let y = 0; y < numPointsHeight; y++) {\r
- for (let x = 0; x < numPointsWidth; x++) {\r
- if (x < numPointsWidth-1) {\r
- this.constraints.push(new Constraint(\r
- this.particles[this.getVertexIndex(x, y)],\r
- this.particles[this.getVertexIndex(x+1, y)],\r
- REST_DIST_X\r
- ));\r
- }\r
- if (x < numPointsWidth-1) {\r
- this.constraints.push(new Constraint(\r
- this.particles[this.getVertexIndex(x, y)],\r
- this.particles[this.getVertexIndex(x, y+1)],\r
- REST_DIST_Y\r
- ));\r
- }\r
- }\r
- }\r
- }\r
- generateGeometry() {\r
- const geometry = new THREE.BufferGeometry();\r
-\r
- const vertices = [];\r
- const normals = [];\r
- const indices = [];\r
-\r
- for (let particle of this.particles) {\r
- vertices.push(\r
- particle.position.x,\r
- particle.position.y,\r
- particle.position.z);\r
- }\r
-\r
- const numPointsWidth = this.numPointsWidth;\r
- const numPointsHeight = this.numPointsHeight;\r
-\r
- /**\r
- * generate faces based on 4 vertices\r
- * and 6 springs each\r
- */\r
- for (let y = 0; y < numPointsHeight - 1; y++) {\r
- for (let x = 0; x < numPointsWidth - 1; x++) {\r
- indices.push(\r
- this.getVertexIndex(x, y),\r
- this.getVertexIndex(x+1, y),\r
- this.getVertexIndex(x+1, y+1)\r
- );\r
- indices.push(\r
- this.getVertexIndex(x, y),\r
- this.getVertexIndex(x+1, y+1),\r
- this.getVertexIndex(x, y+1)\r
- );\r
- }\r
- }\r
-\r
- geometry.setIndex(indices);\r
- geometry.setAttribute('position', new THREE.Float32BufferAttribute(vertices, 3));\r
- //geometry.setAttribute('normal', new THREE.Float32BufferAttribute(normals, 3));\r
- geometry.computeBoundingSphere();\r
- geometry.computeVertexNormals();\r
-\r
- return geometry;\r
- }\r
- updateGeometry(geometry) {\r
-\r
- }\r
- satisfyConstraints() {\r
-\r
- }\r
- simulate() {\r
-\r
- }\r
- /**\r
- * helper function to calculate index of vertex\r
- * in "vertices" array based on its x and y positions\r
- * in the mesh\r
- * @param {number} x - x index of vertex\r
- * @param {number} y - y index of vertex\r
- */\r
- getVertexIndex(x, y) {\r
- return y * this.numPointsWidth + x;\r
- }\r
-}
\ No newline at end of file