Aspose.Slides for C++: Unable to Recognize Some Special Characters

中文技术支持
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@zhangdw

Summary
When converting a presentation with Aspose.Slides for C++ some special or Unicode characters may appear garbled or be missing.

Why it happens

  1. The presentation uses a font that is not available on the machine and the font is not embedded in the file.
  2. The required glyph is not present in the primary font and no suitable fallback font is configured.
  3. Font‑fallback settings may be incomplete for the Unicode range you need.

What to do next

  1. Verify font availability – Open the PPTX in PowerPoint and check which fonts are missing. Install any missing fonts on the operating system or embed the fonts in the presentation (PowerPoint → File → Options → Save → Embed fonts in the file).
  2. Make the required fonts visible to Aspose.Slides – Configure the library to search a folder that contains the needed TrueType/OpenType files. The product documentation describes how to set a custom fonts folder.
  3. Configure a fallback‑font list – Add fonts that cover a wide Unicode range (e.g., Arial Unicode MS, Noto Sans, Segoe UI Symbol) to the fallback list as described in the Aspose.Slides for C++ guide.
  4. Enable diagnostic logging – Turn on debug‑level logging (the SDK provides a logging API) and inspect the log file for messages such as “font not found” or “using fallback”.
  5. Create a minimal reproducible sample – Write a small program that loads the problematic PPTX with the custom font settings and saves it to PDF/PNG. Run it on the same machine; if the characters render correctly, the issue is related to font availability or fallback configuration in your original code.
  6. If the problem persists –
  • Confirm that the fonts you added actually contain the required glyphs (use a font viewer).
  • Gather the exact Aspose.Slides for C++ version you are using and a small PPTX that reproduces the issue.
  • Share the relevant code snippet with Aspose support so they can investigate further.

These steps should help you identify whether missing or mis‑configured fonts are the root cause of the garbled characters.

Note: The above guidance is based on common troubleshooting practices for font‑related rendering issues in Aspose.Slides. Specific API names and exact code snippets should be verified against the official Aspose.Slides for C++ documentation.

:warning: I could not fully verify this explanation against the retrieved sources. Please double-check the behaviour in your environment and confirm the exact SDK/version.

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@zhangdw,
感谢您联系免费技术支持。我们需要更多详细信息来调查该问题。请提供以下文件和信息：

  • 示例演示文稿文件（您可以将文件打包为 ZIP 并在此处上传压缩包）。
  • 可重现该错误的代码示例。
  • 出现该错误的操作系统。
  • 您正在使用的 Aspose.Slides 版本。