AE 影视后期特效工程师实战：表达式与脚本驱动的智能动效流程

// 位置弹性表达式（附加在位置属性）
freq = 2.5;      // 振荡频率（Hz）
decay = 1.8;     // 衰减系数
amplitude = 100; // 初始振幅（像素）

t = time - inPoint; // 从图层入点开始
if (t < 0) t = 0;

// 带阻尼的弹簧模型（位移 = 振幅 * sin(2π*freq*t) * exp(-decay*t)）
offset = amplitude * Math.sin(2 * Math.PI * freq * t) * Math.exp(-decay * t);
value + [0, offset] // 在 Y 轴方向弹性运动

// 位置随机游走，适用于摄像机晃动或粒子随机偏移
seed = 12345; // 随机种子，确保可复现
seedRandom(seed, timeless = true);
freq = 0.8;    // 随机变化频率（次/秒）
amp = 50;      // 随机振幅

t = time * freq;
offsetX = noise(t) * amp - amp/2;
offsetY = noise(t + 100) * amp - amp/2;
value + [offsetX, offsetY];

// 批量生成合成.jsx
#target aftereffects

var csvFile = File("~/Desktop/data.csv");
csvFile.open("r");
var lines = csvFile.read().split("\n");
csvFile.close();

var compWidth = 1920;
var compHeight = 1080;
var frameRate = 30;
var duration = 5; // 秒

for (var i = 1; i < lines.length; i++) { // 跳过表头
    var parts = lines[i].split(",");
    if (parts.length < 3) continue;
    var name = parts[0];
    var score = parseInt(parts[1]);
    var rank = parseInt(parts[2]);
    
    // 创建合成
    var comp = app.project.items.addComp(name + "_Rank" + rank, compWidth, compHeight, 1, duration, frameRate);
    comp.openInViewer();
    
    // 创建背景图层（纯色）
    var bg = comp.layers.addSolid([0.2, 0.2, 0.3], "Background", compWidth, compHeight, 1);
    bg.moveToBeginning();
    
    // 创建文字图层（名字）
    var txtLayer = comp.layers.addText(name);
    var txtDoc = txtLayer.property("Source Text").value;
    txtDoc.fontSize = 120;
    txtDoc.fillColor = [1, 1, 1];
    txtDoc.font = "Arial Bold";
    txtLayer.property("Source Text").setValue(txtDoc);
    
    // 位置居中（X 轴居中，Y 轴随排名变化）
    var yPos = 400 + rank * 80;
    txtLayer.property("Position").setValue([compWidth/2, yPos]);
    
    // 添加缩放动画（从 0 到 100% 弹性）
    var scaleProp = txtLayer.property("Scale");
    // 在 0 秒设关键帧为 [0,0]
    scaleProp.setValueAtTime(0, [0, 0]);
    // 在 1 秒设关键帧为 [120,120]（过冲）
    scaleProp.setValueAtTime(1, [120, 120]);
    // 在 1.5 秒设关键帧为 [100,100]
    scaleProp.setValueAtTime(1.5, [100, 100]);
    // 应用缓动（Easy Ease）
    var key1 = scaleProp.keyframe(1);
    key1.easeOut = [0.2, 0.8];
    var key2 = scaleProp.keyframe(2);
    key2.easeIn = [0.8, 0.2];
}

// 在形状图层上创建路径（数据点）
function createChart(dataPoints, comp) {
    var shapeLayer = comp.layers.addShape();
    var shapeGroup = shapeLayer.property("ADBE Root Vectors Group");
    var pathGroup = shapeGroup.addProperty("ADBE Vector Shape - Group");
    var pathProp = pathGroup.property("ADBE Vector Shape");
    
    var points = [];
    var spacing = comp.width / (dataPoints.length - 1);
    var baseY = comp.height * 0.8;
    var scaleY = comp.height * 0.6;
    
    for (var i = 0; i < dataPoints.length; i++) {
        var x = i * spacing;
        var y = baseY - dataPoints[i] / 100 * scaleY;
        points.push([x, y]);
    }
    
    // 构建贝塞尔路径（使用 Catmull-Rom 插值平滑）
    var vertices = [];
    var inTangents = [];
    var outTangents = [];
    for (var i = 0; i < points.length; i++) {
        vertices.push(points[i]);
        // 切线计算（简化）
        if (i === 0) {
            inTangents.push([0, 0]);
            outTangents.push([(points[1][0]-points[0][0])/3, (points[1][1]-points[0][1])/3]);
        } else if (i === points.length-1) {
            inTangents.push([(points[i][0]-points[i-1][0])/3, (points[i][1]-points[i-1][1])/3]);
            outTangents.push([0, 0]);
        } else {
            var dx = points[i+1][0] - points[i-1][0];
            var dy = points[i+1][1] - points[i-1][1];
            inTangents.push([-dx/6, -dy/6]);
            outTangents.push([dx/6, dy/6]);
        }
    }
    var pathValue = pathProp.value;
    pathValue.vertices = vertices;
    pathValue.inTangents = inTangents;
    pathValue.outTangents = outTangents;
    pathValue.closed = false;
    pathProp.setValue(pathValue);
    
    // 添加描边
    var stroke = shapeGroup.addProperty("ADBE Vector Stroke - Group");
    stroke.property("ADBE Vector Stroke Color").setValue([1, 0.5, 0]);
    stroke.property("ADBE Vector Stroke Width").setValue(4);
    
    // 添加路径修剪（Trim Paths）实现绘制动画
    var trim = shapeGroup.addProperty("ADBE Vector Trim - Group");
    trim.property("ADBE Vector Trim End").setValueAtTime(0, 0);
    trim.property("ADBE Vector Trim End").setValueAtTime(2, 100);
}

function renderComp(comp, outputPath) {
    var renderQueue = app.project.renderQueue;
    var item = renderQueue.items.add(comp);
    item.outputModule(1).file = new File(outputPath);
    item.outputModule(1).applyTemplate("H.264 - 1080p 30");
    item.render = true;
}
// 遍历所有合成，调用 renderComp