AUTOCAD 2018支持PDF導入了？

上A網翻東西的時候突然發現以下文字，請用過的講解一下。

ou can import the geometry, fills, raster images, and TrueType text from a PDF file into the current drawing. The visual fidelity along with some properties such as PDF scale, layers, lineweights, and colors can be preserved.

PDF files are a common way of publishing and sharing design data for review and markup. AutoCAD supports creating PDF files as a publishing output for AutoCAD drawings, and importing PDF data into AutoCAD using either of two options:

• PDF files can be attached to drawings as underlays, which can be used as a reference when collaborating on projects.
• PDF data can be imported as objects, in part or entirely, which can be used a reference and also modified.

If you import PDF data, you can choose to specify a page from a PDF file or you can convert all or part of an attached PDF underlay into AutoCAD objects.

How Objects are Translated

When a PDF file is generated, all supported objects are translated into paths, fills, raster images, markups, and TrueType text. In PDF, paths are composed of line segments and cubic Bézier curves, either connected or independent. However, when a PDF file is imported into AutoCAD-based products, note the following:

• Bézier curves are converted into circles and arcs if they are within a reasonable tolerance to those shapes. Otherwise, they are converted into 2D polylines.
• Elliptical shapes can be converted into 2D polylines, splines, or ellipses depending on how they were stored in the PDF.
• As an option, each set of approximately collinear segments can be combined into a polyline with a dashed linetype named PDF_Import.
• Compound objects such as dimensions, leaders, patterned hatches, and tables result in many separate objects as if these objects were exploded.
• Solid-filled areas are imported as 2D solids, or optionally as solid-filled hatches. They are assigned a 50% transparency to make sure that any text within the areas is visible.
• Text that used TrueType fonts is preserved, but text that originally used SHX fonts is imported as separate geometric objects.
• Raster images generate PNG format files that are attached to the drawing file as external references. These image files are saved in a folder specified by the PDFIMPORTIMAGEPATH system variable, which can also be specified in the Options dialog box, Files tab.
• Point objects are converted to zero-length polylines.
• Markups are not imported.

試過了，但是功能有限制。

1、PDF必須是CAD或其它軟體直接導出的矢量PDF；複印機掃描紙質圖紙生成的掃描PDF不行，CAD導出的PDF再經過虛擬列印生成的柵格化PDF也不行。

2、導入到CAD中只是變成了一堆多段線，標註也是一堆打散的多段線，比例當然是不對的，各個對象間的相對位置也是不對的，shx文字也是變成了多段線，只有truetype字體可以保留為文字。

3、CAD2018的Express Tools提供了將多段線重新轉化為shx/truetype文字的工具，但是只能識別英文和阿拉伯數字；小數點無法識別，漢字無法識別。

測試文件對比：http://pan.baidu.com/s/1pLntjMr