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# ReadingTypeEnum

ReadingTypeEnum enumeration constants are used to describe the reading type of a text. A text on page can be written in horizontal lines, or vertical lines.

```
typedef enum {
 TRT_Unknown,
 TRT_LinesBased,
 TRT_ColumnsBased
} ReadingTypeEnum;
```

## Elements

| Name                | Description                                                                                                                              |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| TRT\\\_ColumnsBased | The text is written in vertical lines.                                                                                                   |
| TRT\\\_LinesBased   | The text is written in horizontal lines.                                                                                                 |
| TRT\\\_Unknown      | The reading type is undefined. For a newly created text block, this constant means that text direction should be detected automatically. |

## Used in

[ITextOrientation::ReadingType](/fine-reader/engine/api-reference/text-related-objects/textorientation#readingtype)