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{"version":3,"file":"RopeGeometry.mjs","sources":["../../src/geometry/RopeGeometry.ts"],"sourcesContent":["import { MeshGeometry } from '@pixi/mesh';\n\nimport type { IPoint } from '@pixi/core';\n\n/**\n * RopeGeometry allows you to draw a geometry across several points and then manipulate these points.\n * @example\n * import { Point, RopeGeometry } from 'pixi.js';\n *\n * for (let i = 0; i < 20; i++) {\n * points.push(new Point(i * 50, 0));\n * };\n * const rope = new RopeGeometry(100, points);\n * @memberof PIXI\n */\nexport class RopeGeometry extends MeshGeometry\n{\n /** An array of points that determine the rope. */\n public points: IPoint[];\n\n /** Rope texture scale, if zero then the rope texture is stretched. */\n public readonly textureScale: number;\n\n /**\n * The width (i.e., thickness) of the rope.\n * @readonly\n */\n _width: number;\n\n /**\n * @param width - The width (i.e., thickness) of the rope.\n * @param points - An array of {@link PIXI.Point} objects to construct this rope.\n * @param textureScale - By default the rope texture will be stretched to match\n * rope length. If textureScale is positive this value will be treated as a scaling\n * factor and the texture will preserve its aspect ratio instead. To create a tiling rope\n * set baseTexture.wrapMode to {@link PIXI.WRAP_MODES.REPEAT} and use a power of two texture,\n * then set textureScale=1 to keep the original texture pixel size.\n * In order to reduce alpha channel artifacts provide a larger texture and downsample -\n * i.e. set textureScale=0.5 to scale it down twice.\n */\n constructor(width = 200, points: IPoint[], textureScale = 0)\n {\n super(new Float32Array(points.length * 4),\n new Float32Array(points.length * 4),\n new Uint16Array((points.length - 1) * 6));\n\n this.points = points;\n this._width = width;\n this.textureScale = textureScale;\n\n this.build();\n }\n\n /**\n * The width (i.e., thickness) of the rope.\n * @readonly\n */\n get width(): number\n {\n return this._width;\n }\n\n /** Refreshes Rope indices and uvs */\n private build(): void\n {\n const points = this.points;\n\n if (!points) return;\n\n const vertexBuffer = this.getBuffer('aVertexPosition');\n const uvBuffer = this.getBuffer('aTextureCoord');\n const indexBuffer = this.getIndex();\n\n // if too little points, or texture hasn't got UVs set yet just move on.\n if (points.length < 1)\n {\n return;\n }\n\n // if the number of points has changed we will need to recreate the arraybuffers\n if (vertexBuffer.data.length / 4 !== points.length)\n {\n vertexBuffer.data = new Float32Array(points.length * 4);\n uvBuffer.data = new Float32Array(points.length * 4);\n indexBuffer.data = new Uint16Array((points.length - 1) * 6);\n }\n\n const uvs = uvBuffer.data;\n const indices = indexBuffer.data;\n\n uvs[0] = 0;\n uvs[1] = 0;\n uvs[2] = 0;\n uvs[3] = 1;\n\n let amount = 0;\n let prev = points[0];\n const textureWidth = this._width * this.textureScale;\n const total = points.length; // - 1;\n\n for (let i = 0; i < total; i++)\n {\n // time to do some smart drawing!\n const index = i * 4;\n\n if (this.textureScale > 0)\n {\n // calculate pixel distance from previous point\n const dx = prev.x - points[i].x;\n const dy = prev.y - points[i].y;\n const distance = Math.sqrt((dx * dx) + (dy * dy));\n\n prev = points[i];\n amount += distance / textureWidth;\n }\n else\n {\n // stretch texture\n amount = i / (total - 1);\n }\n\n uvs[index] = amount
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