如何使用CEP/JavaScript/ExtendScript在Photoshop中按坐标绘制线条

路径首尾自动闭合是因为创建子路径时显式开启了闭合属性：

lineSubPathArray.closed = true;

该属性会强制Photoshop自动连接路径的第一个点和最后一个点，生成闭合形状。另外你当前描边参数用的是仅对闭合路径生效的内部描边，开放路径使用该参数会出现渲染异常。

• 关闭路径自动闭合
  找到DrawShape函数中lineSubPathArray.closed = true;，修改为：

lineSubPathArray.closed = false;

• 调整描边位置适配开放路径
  找到stroke_line函数中desc2613.putEnumerated( idLctn, idStrL, idInsd );，替换为以下代码，将描边位置改为开放路径支持的居中描边：

var idCntr = charIDToTypeID("Cntr");
desc2613.putEnumerated( idLctn, idStrL, idCntr );

function DrawShape(arr) 
{
    
    var doc = app.activeDocument;
    var pointCount = arr.length;

    // 获取文档原始高度，用于翻转Y轴坐标适配PS坐标系
    var imageHeight = app.activeDocument.height.value;
    
    var pathPoints = [];
    for (var i = 0; i < pointCount; i++) 
    {
        pathPoints[i] = new PathPointInfo;
        pathPoints[i].kind = PointKind.CORNERPOINT;

        // Y轴坐标翻转
        arr[i][1] = imageHeight - arr[i][1];

        pathPoints[i].anchor = arr[i];
        pathPoints[i].leftDirection = pathPoints[i].anchor;
        pathPoints[i].rightDirection = pathPoints[i].anchor;
    }

    var lineSubPath = new SubPathInfo();
    lineSubPath.closed = false;
    lineSubPath.operation = ShapeOperation.SHAPEADD;
    lineSubPath.entireSubPath = pathPoints;
    var myPathItem = doc.pathItems.add("myPath", [lineSubPath]);
    

    // 路径转选区
    var idsetd = charIDToTypeID( "setd" );
    var desc100 = new ActionDescriptor();
    var idnull = charIDToTypeID( "null" );
    var ref24 = new ActionReference();
    var idChnl = charIDToTypeID( "Chnl" );
    var idfsel = charIDToTypeID( "fsel" );
    ref24.putProperty( idChnl, idfsel );
    desc100.putReference( idnull, ref24 );
    var idT = charIDToTypeID( "T   " );
    var ref25 = new ActionReference();
    var idPath = charIDToTypeID( "Path" );
    var idOrdn = charIDToTypeID( "Ordn" );
    var idTrgt = charIDToTypeID( "Trgt" );
    ref25.putEnumerated( idPath, idOrdn, idTrgt );
    desc100.putReference( idT, ref25 );
    var idVrsn = charIDToTypeID( "Vrsn" );
    desc100.putInteger( idVrsn, 1 );
    var idvectorMaskParams = stringIDToTypeID( "vectorMaskParams" );
    desc100.putBoolean( idvectorMaskParams, true );
    executeAction( idsetd, desc100, DialogModes.NO );


    // 按参数描边
    stroke_line(2, 215, 5, 5);

    // 取消路径选中状态
    deselect_path();

    // 取消选区
    app.activeDocument.selection.deselect();
}


function stroke_line(strokewidth, R, G, B)
{
    var idStrk = charIDToTypeID( "Strk" );
    var desc2613 = new ActionDescriptor();
    var idWdth = charIDToTypeID( "Wdth" );
    desc2613.putInteger( idWdth, strokewidth );
    var idLctn = charIDToTypeID( "Lctn" );
    var idStrL = charIDToTypeID( "StrL" );
    // 开放路径使用居中描边
    var idCntr = charIDToTypeID("Cntr");
    desc2613.putEnumerated( idLctn, idStrL, idCntr );
    var idOpct = charIDToTypeID( "Opct" );
    var idPrc = charIDToTypeID( "#Prc" );
    desc2613.putUnitDouble( idOpct, idPrc, 100.000000 );
    var idMd = charIDToTypeID( "Md  " );
    var idBlnM = charIDToTypeID( "BlnM" );
    var idNrml = charIDToTypeID( "Nrml" );
    desc2613.putEnumerated( idMd, idBlnM, idNrml );
    var idClr = charIDToTypeID( "Clr " );
    var desc2614 = new ActionDescriptor();
    var idRd = charIDToTypeID( "Rd  " );
    desc2614.putDouble( idRd, R );
    var idGrn = charIDToTypeID( "Grn " );
    desc2614.putDouble( idGrn, G );
    var idBl = charIDToTypeID( "Bl  " );
    desc2614.putDouble( idBl, B );
    var idRGBC = charIDToTypeID( "RGBC" );
    desc2613.putObject( idClr, idRGBC, desc2614 );
    executeAction( idStrk, desc2613, DialogModes.NO );
}

function deselect_path()
{
    var idDslc = charIDToTypeID( "Dslc" );
    var desc154 = new ActionDescriptor();
    var idNull = charIDToTypeID( "null" );
    var ref127 = new ActionReference();
    var idPath = charIDToTypeID( "Path" );
    ref127.putClass( idPath );
    desc154.putReference( idNull, ref127 );
    executeAction( idDslc, desc154, DialogModes.NO );
}

你提供的坐标序列中存在大量连续重复点，绘制前可以先做一轮去重过滤，能有效减少描边时出现的顿挫、粗细不均问题。

内容的提问来源于stack exchange，提问作者Fitspade