Does it support the TransformBy method for objects?

[Sring65]

atuocad TransformBy method

[DomCR]

Hi @Sring65,

Check:

ACadSharp/src/ACadSharp/Entities/Entity.cs

Line 137 in 8fc0862

public abstract void ApplyTransform(Transform transform);

Hope this helps!

[Sring65]

Hi DomCR
My Autodesk VBA code is similar, yet the results differ. Could you check what’s wrong with the syntax?
testfile: https://1drv.ms/u/c/507b2de78c13dcb2/EbS4RvdfiZhGoj9H34fmyVoBlYIMoUV9iMDWmaoaLGkTog?e=KoIOj2


Some objects are not supported

vab `
'=====================================================================================
' Purpose: Apply a four-parameter coordinate transformation to all objects in Model Space.
' Method: Uses the object.TransformBy method with a 4x4 transformation matrix.
' Parameters:
' - Easting (X Translation): -1593123.632143
' - Northing (Y Translation): -2921123.628578
' - Rotation (in Radians): -0.9197705519
' - Scale Factor: 0.98
' =====================================================================================

Public Sub ApplyFourParameterTransformation()
' --- 1. Define Four Parameters ---
Dim dX As Double
Dim dY As Double
Dim rotation As Double
Dim scaleNumber As Double

dX = -1593123.632
dY = -2921123.638
rotation = -0.92  ' Note: This value is in radians
scaleNumber = 0.998

Dim matrix(0 To 3, 0 To 3) As Double

' Initialize as an identity matrix
matrix(0, 0) = 1: matrix(0, 1) = 0: matrix(0, 2) = 0: matrix(0, 3) = 0
matrix(1, 0) = 0: matrix(1, 1) = 1: matrix(1, 2) = 0: matrix(1, 3) = 0
matrix(2, 0) = 0: matrix(2, 1) = 0: matrix(2, 2) = 1: matrix(2, 3) = 0
matrix(3, 0) = 0: matrix(3, 1) = 0: matrix(3, 2) = 0: matrix(3, 3) = 1

' Populate the rotation and scaling part (top-left 2x2 sub-matrix)
matrix(0, 0) = scaleNumber * Cos(rotation)
matrix(0, 1) = -scaleNumber * Sin(rotation)
matrix(1, 0) = scaleNumber * Sin(rotation)
matrix(1, 1) = scaleNumber * Cos(rotation)
matrix(2, 2) = scaleNumber
matrix(0, 3) = dX
matrix(1, 3) = dY

' --- 3. Get the active document and Model Space ---
Dim doc As AcadDocument
Dim modelSpace As AcadBlock
Set doc = ThisDrawing
Set modelSpace = doc.modelSpace

' --- 4. Iterate through all objects and apply the transformation ---
Dim obj As AcadObject
Dim transformedCount As Long

transformedCount = 0
On Error Resume Next ' Add error handling in case some objects cannot be transformed

For Each obj In modelSpace
    ' The TransformBy method is effective for most entities.
    ' Some objects, like dimension styles or layers, do not support this method and will raise an error.
    obj.TransformBy matrix
    If Err.Number = 0 Then
        transformedCount = transformedCount + 1
    Else
        ' You can print the names of objects that failed to transform for debugging purposes.
        Debug.Print "Could not transform object: " & obj.ObjectName & ", Error: " & Err.Description
        Err.Clear
    End If
Next obj

On Error GoTo 0 ' Restore default error handling

' --- 5. Completion Message ---
doc.Regen acAllViewports ' Regenerate all viewports to show the changes
MsgBox "Coordinate transformation complete!" & vbCrLf & _
       "Successfully transformed " & transformedCount & " objects.", _
       vbInformation, "Transformation Complete"

End Sub`

C# `
using ACadSharp;
using ACadSharp.Entities;
using ACadSharp.IO;
using ACadSharp.Tables;
using CSMath;
using System;
using System.IO;
using System.Numerics;
using static ACadSharp.Objects.XRecord;

public class CadTransformer
{
public static void Main(string[] args)
{
string inputFilePath = @"C:\Users\admin\Desktop\dwgtest\sample.dwg";
string outputFilePath = @"C:\Users\admin\Desktop\dwgtest\sample_transformed.dwg";

    if (!File.Exists(inputFilePath))
    {
        Console.ForegroundColor = ConsoleColor.Red;
        Console.WriteLine($"Error: Input file not found: {inputFilePath}");
        Console.ResetColor();
        return;
    }

    // --- 2. Define Four Parameters as float ---
    double dX = -1593123.632;
    double dY = -2921123.638;
    double rotation = -0.92;
    double scale = 0.998;

    // --- 3. Create the Transformation Matrix ---
    Matrix4 transformationMatrix = new Matrix4(
                                    1,0,0,0,
                                    0,1,0,0,
                                    0,0,1,0,
                                    0,0,0,1);
    transformationMatrix.M00 = scale * Math.Cos(rotation);
    transformationMatrix.M01 = -scale * Math.Sin(rotation);
    transformationMatrix.M10 = scale * Math.Sin(rotation);
    transformationMatrix.M11 = scale * Math.Cos(rotation);
    transformationMatrix.M22 = scale;
    transformationMatrix.M03 = dX;
    transformationMatrix.M13 = dY;

    try
    {
        // --- 4. Read the DWG File ---
        Console.WriteLine($"Reading file: {inputFilePath}...");
        CadDocument doc = DwgReader.Read(inputFilePath);
        Console.WriteLine("File read successfully.");

        int transformedCount = 0;
        int errorCount=0;
        // --- 5. Transform entities in Model Space ---
        Console.WriteLine("Transforming entities in Model Space...");
        Transform tran = new Transform(transformationMatrix);
        foreach (Entity entity in doc.ModelSpace.Entities)
        {
            try
            {
                entity.ApplyTransform(tran);
                transformedCount++;
            }
            catch(Exception ex)
            {
                errorCount++;
                Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine("entityType:" + entity.GetType());
                Console.ResetColor();
                Console.WriteLine(ex.ToString());
            }                            
        }


        Console.WriteLine($"Successfully transformed a total of {transformedCount} objects.");

        // --- 7. Save the Transformed DWG File ---
        Console.WriteLine($"Saving to new file: {outputFilePath}...");
        DwgWriter.Write(outputFilePath, doc);
        Console.WriteLine("File saved successfully.");

        Console.ForegroundColor = ConsoleColor.Green;
        Console.WriteLine("\nCoordinate transformation complete!");
        Console.ResetColor();

        if (errorCount != 0)
        {
            Console.ForegroundColor = ConsoleColor.Red;
            Console.WriteLine("fail Count:" + errorCount);
            Console.ResetColor();
        }
        
    }
    catch (Exception ex)
    {
        Console.ForegroundColor = ConsoleColor.Red;
        Console.WriteLine($"An error occurred: {ex.Message}");
        Console.ResetColor();
    }
}

}
`

[DomCR]

Instead of creating the Matrix yourself, have you tried to use the implemented Transform constructor with the different parameters?

[Sring65]

Excluding unsupported objects, the coordinates converted using the existing parameter method are correct.
Transform tran = new Transform(); tran.Scale = new XYZ(scale,scale, scale); tran.Translation = new XYZ(dX, dY, 0); tran.EulerRotation= new XYZ(0,0 ,rotation);

[DomCR]

I see that the rotation is wrongly applied to some objects.

I'll open a branch to take a look, could you write the entity types that are badly transformed? that would help, thanks.

[Sring65]

https://github.com/Sring65/-ACadSharpTransformertest.git
sample.dwg form https://github.com/haplokuon/netDxf/tree/master/TestDxfDocument

1. rotation error:

Arc
Circle
Ellipse
Point
TextEntity
Line
MText

2. not move :

DimensionLinear
DimensionAngular3Pt
DimensionAngular2Line
DimensionRadius
DimensionDiameter
DimensionOrdinate
DimensionAligned
3. runing Error : Hatch

4. Transform distortion: Insert、RasterImage、Wipeout、PdfUnderlay、MLine、Leader
5. some Style Missing： GSA line、DOT
6. xdata Missing
7. Default show Lineweight Missing
8. ACadSharp not read support：Polygon Mesh、Shape、ACAD_TABLE