core: 考虑到美观程度去掉了定时更换控制点的代码

core: 整理了随机控制点生成器代码

package.json

@@ -6,5 +6,6 @@
     "@biomejs/biome": "^1.9.4",
     "lerna": "^8.1.9",
     "typescript": "^5.7.3"
-  }
-}
+  },
+  "packageManager": "[email protected]+sha512.398035c7bd696d0ba0b10a688ed558285329d27ea994804a52bad9167d8e3a72bcb993f9699585d3ca25779ac64949ef422757a6c31102c12ab932e5cbe5cc92"
+}

packages/core/src/bg-render/mesh-renderer/cp-generate.ts

@@ -0,0 +1,214 @@
+/**
+ * @fileoverview
+ * 实验性的随机控制点生成函数算法
+ * 目的是取代原先大量的预设控制点代码
+ */
+
+import {
+	type ControlPointConf,
+	type ControlPointPreset,
+	p,
+	preset,
+} from "./cp-presets.ts";
+
+const randomRange = (min: number, max: number): number =>
+	Math.random() * (max - min) + min;
+
+function clamp(x: number, min: number, max: number): number {
+	return Math.min(Math.max(x, min), max);
+}
+
+function smoothstep(edge0: number, edge1: number, x: number): number {
+	const t = clamp((x - edge0) / (edge1 - edge0), 0, 1);
+	return t * t * (3 - 2 * t);
+}
+
+function smoothifyControlPoints(
+	conf: ControlPointConf[],
+	w: number,
+	h: number,
+	iterations = 2,
+	factor = 0.5,
+	factorIterationModifier = 0.1,
+): void {
+	let grid: ControlPointConf[][] = [];
+	let f = factor;
+
+	for (let j = 0; j < h; j++) {
+		grid[j] = [];
+		for (let i = 0; i < w; i++) {
+			grid[j][i] = conf[j * w + i];
+		}
+	}
+
+	const kernel = [
+		[1, 2, 1],
+		[2, 4, 2],
+		[1, 2, 1],
+	];
+	const kernelSum = 16;
+
+	for (let iter = 0; iter < iterations; iter++) {
+		const newGrid: ControlPointConf[][] = [];
+		for (let j = 0; j < h; j++) {
+			newGrid[j] = [];
+			for (let i = 0; i < w; i++) {
+				if (i === 0 || i === w - 1 || j === 0 || j === h - 1) {
+					newGrid[j][i] = grid[j][i];
+					continue;
+				}
+				let sumX = 0;
+				let sumY = 0;
+				let sumUR = 0;
+				let sumVR = 0;
+				let sumUP = 0;
+				let sumVP = 0;
+				for (let dj = -1; dj <= 1; dj++) {
+					for (let di = -1; di <= 1; di++) {
+						const weight = kernel[dj + 1][di + 1];
+						const nb = grid[j + dj][i + di];
+						sumX += nb.x * weight;
+						sumY += nb.y * weight;
+						sumUR += nb.ur * weight;
+						sumVR += nb.vr * weight;
+						sumUP += nb.up * weight;
+						sumVP += nb.vp * weight;
+					}
+				}
+				const avgX = sumX / kernelSum;
+				const avgY = sumY / kernelSum;
+				const avgUR = sumUR / kernelSum;
+				const avgVR = sumVR / kernelSum;
+				const avgUP = sumUP / kernelSum;
+				const avgVP = sumVP / kernelSum;
+
+				const cur = grid[j][i];
+				const newX = cur.x * (1 - f) + avgX * f;
+				const newY = cur.y * (1 - f) + avgY * f;
+				const newUR = cur.ur * (1 - f) + avgUR * f;
+				const newVR = cur.vr * (1 - f) + avgVR * f;
+				const newUP = cur.up * (1 - f) + avgUP * f;
+				const newVP = cur.vp * (1 - f) + avgVP * f;
+				newGrid[j][i] = p(i, j, newX, newY, newUR, newVR, newUP, newVP);
+			}
+		}
+		grid = newGrid;
+		f = Math.min(1, Math.max(f + factorIterationModifier, 0));
+	}
+
+	for (let j = 0; j < h; j++) {
+		for (let i = 0; i < w; i++) {
+			conf[j * w + i] = grid[j][i];
+		}
+	}
+}
+
+function noise(x: number, y: number): number {
+	return fract(Math.sin(x * 12.9898 + y * 78.233) * 43758.5453);
+}
+
+function fract(x: number): number {
+	return x - Math.floor(x);
+}
+
+function smoothNoise(x: number, y: number): number {
+	const x0 = Math.floor(x);
+	const y0 = Math.floor(y);
+	const x1 = x0 + 1;
+	const y1 = y0 + 1;
+
+	const xf = x - x0;
+	const yf = y - y0;
+
+	const u = xf * xf * (3 - 2 * xf);
+	const v = yf * yf * (3 - 2 * yf);
+
+	const n00 = noise(x0, y0);
+	const n10 = noise(x1, y0);
+	const n01 = noise(x0, y1);
+	const n11 = noise(x1, y1);
+
+	const nx0 = n00 * (1 - u) + n10 * u;
+	const nx1 = n01 * (1 - u) + n11 * u;
+
+	return nx0 * (1 - v) + nx1 * v;
+}
+
+function computeNoiseGradient(
+	perlinFn: (x: number, y: number) => number,
+	x: number,
+	y: number,
+	epsilon = 0.001,
+): [number, number] {
+	const n1 = perlinFn(x + epsilon, y);
+	const n2 = perlinFn(x - epsilon, y);
+	const n3 = perlinFn(x, y + epsilon);
+	const n4 = perlinFn(x, y - epsilon);
+	const dx = (n1 - n2) / (2 * epsilon);
+	const dy = (n3 - n4) / (2 * epsilon);
+	const len = Math.sqrt(dx * dx + dy * dy) || 1;
+	return [dx / len, dy / len];
+}
+
+export function generateControlPoints(
+	width: number,
+	height: number,
+	variationFraction = randomRange(0.4, 0.6), // = 0.2,
+	normalOffset = randomRange(0.3, 0.6), // = 0.3,
+	blendFactor = 0.8,
+	smoothIters = Math.floor(randomRange(3, 5)), // = 3,
+	smoothFactor = randomRange(0.2, 0.3), // = 0.3,
+	smoothModifier = randomRange(-0.1, -0.05), // = -0.05,
+): ControlPointPreset {
+	const w = width ?? Math.floor(randomRange(3, 6));
+	const h = height ?? Math.floor(randomRange(3, 6));
+
+	const conf: ControlPointConf[] = [];
+	const dx = w === 1 ? 0 : 2 / (w - 1);
+	const dy = h === 1 ? 0 : 2 / (h - 1);
+
+	for (let j = 0; j < h; j++) {
+		for (let i = 0; i < w; i++) {
+			const baseX = (w === 1 ? 0 : i / (w - 1)) * 2 - 1;
+			const baseY = (h === 1 ? 0 : j / (h - 1)) * 2 - 1;
+
+			const isBorder = i === 0 || i === w - 1 || j === 0 || j === h - 1;
+			const pertX = isBorder
+				? 0
+				: randomRange(-variationFraction * dx, variationFraction * dx);
+			const pertY = isBorder
+				? 0
+				: randomRange(-variationFraction * dy, variationFraction * dy);
+			let x = baseX + pertX;
+			let y = baseY + pertY;
+
+			const ur = isBorder ? 0 : randomRange(-60, 60);
+			const vr = isBorder ? 0 : randomRange(-60, 60);
+			const up = isBorder ? 1 : randomRange(0.8, 1.2);
+			const vp = isBorder ? 1 : randomRange(0.8, 1.2);
+
+			if (!isBorder) {
+				const uNorm = (baseX + 1) / 2;
+				const vNorm = (baseY + 1) / 2;
+
+				const [nx, ny] = computeNoiseGradient(smoothNoise, uNorm, vNorm, 0.001);
+				let offsetX = nx * normalOffset;
+				let offsetY = ny * normalOffset;
+
+				const distToBorder = Math.min(uNorm, 1 - uNorm, vNorm, 1 - vNorm); // in [0,0.5]
+
+				const weight = smoothstep(0, 1.0, distToBorder);
+				offsetX *= weight;
+				offsetY *= weight;
+
+				x = x * (1 - blendFactor) + (x + offsetX) * blendFactor;
+				y = y * (1 - blendFactor) + (y + offsetY) * blendFactor;
+			}
+			conf.push(p(i, j, x, y, ur, vr, up, vp));
+		}
+	}
+
+	smoothifyControlPoints(conf, w, h, smoothIters, smoothFactor, smoothModifier);
+
+	return preset(w, h, conf);
+}