Help for DWG/DXF to Pdf app

[DomCR]

#89 (comment)

@LeonidKaralis1993 please reply into this discussion about your topic.

[DomCR]

@LeonidKaralis1993

Hello!
Thanks for your teaching.
Now, I have problem to get the string of MTEXT.
I can't get the correct string values from MTEXT entities, I have got "SEE" to use 'Value' property .
What's the reason?

For this issue you can open an issue into this repository to treat this specific matter, please give detailed information and some examples of the MText that you cannot read, if you can give an specific dwg file to test it that would be very helpful.

[LeonidKaralis1993]

Thanks for your help!
I've created a repository https://github.com/LeonidKaralis1993/ACAD_C-.git .
It contains "sample_files" folder in root directory.

[DomCR]

please review the repo that you send, there is no sample_files folder

[LeonidKaralis1993]

Have added sample_files folder.

[LeonidKaralis1993]

Could you please elaborate on the problem below?
I don't understand AtuoCad Entities, so I'm having a hard time passing him to PDF.
Please send me an explanation of his geometrical properties.
---ARC, LWPOLYLINE, HATCH, INSERT, DIMENSION_LINEAR---
Thank you.

[DomCR]

All the entities have documentation in the code about the different properties, I can summarize which ones have the geometric values:

ARC:

• Center
• StartAngle
• EndAngle

LWPOLYLINE:

• Vertices (is a list of vertices in which each one has a Location)

DIMENSION_LINEAR:

• FirstPoint
• SecondPoint

INSERT:

• InsertPoint
  Insert is a reference to a block, so you will need to access to the property Block and check the different entities in it

HATCH:

• Paths (is a list with the different boundary paths that form this hatch, each one has it's own geometric definitions)

[LeonidKaralis1993]

Thanks very much!
In ARC entity, I insert a code as following.
if (e.ObjectType.ToString() == "ARC")
{
Console.Write("\n\t\t--DrawArc--");
arc = (Arc)e;
xRect.X = arc.Center.X + arc.Radius;
xRect.Y = vh - arc.Center.Y - arc.Radius;
xRect.Width = arc.Radius * 2;
xRect.Height = arc.Radius * 2;
Console.WriteLine(arc.Radius + " " + arc.Center);
gfx.DrawArc(pdfpen, xRect, arc.StartAngle, arc.EndAngle);
}
but the result is a line.
Please teach me about this.
this is my result pdf.
mySample.zip

[DomCR]

Sorry but I don't know how PDFsharp works or handles drawing arcs I cannot help with this matter.

[LeonidKaralis1993]

Resolve this problem thanks for your help.
the code is following
if (e.ObjectType.ToString() == "ARC")
{
Console.Write("\n\t\t--DrawArc--");
double stA,edA;
double goA;
arc = (Arc)e;
xRect.X = arc.Center.X - arc.Radius + 200;
xRect.Y = vh - arc.Center.Y - arc.Radius - 200;
xRect.Width = arc.Radius * 2;
xRect.Height = arc.Radius * 2;

                            if (arc.EndAngle < arc.StartAngle)
                            {
                                stA = 360 - arc.StartAngle / pi * 180;
                                gfx.DrawArc(pdfpen, xRect, 0, stA);
                                edA = 360 - arc.EndAngle / pi * 180;
                                gfx.DrawArc(pdfpen, xRect, edA, 359.999999 - edA);
                                
                            }
                            else {
                                stA = 360 - arc.EndAngle / pi * 180;
                                goA = 360 - arc.StartAngle / pi * 180 - stA;
                                gfx.DrawArc(pdfpen, xRect, stA, goA);          
                           }     
                            
                        }

[LeonidKaralis1993]

Thank you. DomCR!!!
Please let me know about the DIMENSION_LINEAR---FirstPoint & SecondPoint in more detail.
And How to get the "string" in METXT entity.
I used AdditionalText and got a string called "SEE".
What is the cause?

[DomCR]

DIMENSION_LINEAR is as it says, is a line, so you have the first and second point.

About the MTEXT I would need an example to be able to reproduce the error that you are having.

[DomCR]

For more information about the entities check https://help.autodesk.com/view/OARX/2021/ENU/?guid=GUID-7D07C886-FD1D-4A0C-A7AB-B4D21F18E484 this is the documentation that ACadSharp works with.

[LeonidKaralis1993]

Thank you! That's a good point for my project.

[LeonidKaralis1993]

Thank you.
How to get the coordinate properties of DWG/DXF files.
I am trying to get the information of the coordinate system and rearrange it on the PDF page, but the property of the coordinate system of the AutoCAD file is not known.

[DomCR]

Check the CadHeader in the document, you should find the System Variables from Autocad.

[LeonidKaralis1993]

Please tell me the name of the variable.
I'd be very grateful if you could give me a way to get the name of a variable.
Thank you!

[LeonidKaralis1993]

Thanks for your help
Where is the starting point for ARC's startAngle in AutoCad?
-> Where is the point in the area where the ARC pointed to by startAngle=0 is displayed?

[DJGosnell]

Answering all questions related to DWG implementation details would require a substantial amount of time due to their intricate nature. The official specifications are documented in the DXF reference (found at https://github.com/DomCR/ACadSharp/blob/master/reference/autocad_2012_pdf_dxf-reference_enu.pdf) and the less formal DWG references (found at https://github.com/DomCR/ACadSharp/blob/master/reference/OpenDesign_Specification_for_.dwg_files.pdf). For a comprehensive understanding, I would advise reviewing these resources, as the specifications can become quite complex. The information on arcs can be found on page 66 of the DXF documentation.

It is important to note that various libraries may have different methods of representing arcs and ellipses, and conversion may be necessary to match the representation used by your library. Ellipses, in particular, can pose challenges.

[LeonidKaralis1993]

thank you.

[LeonidKaralis1993]

Have Sucess! Thank you.
Your help has played a big role.
if (e.ObjectType.ToString() == "ARC")
{
Console.Write("\n\t\t--DrawArc--");
double stA,edA;
double goA;
arc = (Arc)e;
xRect.X = arc.Center.X - arc.Radius + 200;
xRect.Y = vh - arc.Center.Y - arc.Radius - 200;
xRect.Width = arc.Radius * 2;
xRect.Height = arc.Radius * 2;

                            if (arc.EndAngle < arc.StartAngle)
                            {
                                stA = 360 - arc.StartAngle / pi * 180;
                                gfx.DrawArc(pdfpen, xRect, 0, stA);
                                edA = 360 - arc.EndAngle / pi * 180;
                                gfx.DrawArc(pdfpen, xRect, edA, 359.999999 - edA);
                                
                            }
                            else {
                                stA = 360 - arc.EndAngle / pi * 180;
                                goA = 360 - arc.StartAngle / pi * 180 - stA;
                                gfx.DrawArc(pdfpen, xRect, stA, goA);          
                           }     
                            
                        }

[LeonidKaralis1993]

Thank you, everyone.
LWPOLYLINE, HATCH, INSERT, DIMENSION_LINEAR
A comprehensive explanation of how to draw with properties is needed.
Just sending me the URL would be greatly appreciated.

[LeonidKaralis1993]

Thank you.
I am trying to convert DXF files, but an error occurred in the reading function.
Please explain the differences between DXF and DWG files and the main points in drawing.

[LeonidKaralis1993]

The project under development is almost complete.
Please look at the generated PDF file and give me your advice.