LFile::EnumGeoKeysCallBack
#include "ltwrappr.h"
virtual L_INT LFile::EnumGeoKeysCallBack(uTag, uType, uCount, pData)
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L_UINT16 uTag; |
/* GeoKey ID */ |
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L_UINT16 uType; |
/* GeoKey type */ |
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L_UINT uCount; |
/* number of GeoKey values */ |
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L_VOID * pData; |
/* pointer to GeoKey data */ |
This function is called for each GeoKey enumerated by the LFile::EnumGeoKeys function.
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Parameter |
Description |
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uTag |
GeoKey ID identifying the GeoTIFF key. |
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uType |
The type of GeoKey. This indicates whether the data pointed to by pData is SHORT, DOUBLE or ASCII. Possible values are: |
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Value |
Meaning |
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TAG_ASCII |
[2] Byte in the range of 0 to 255. Null-terminated. |
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TAG_SHORT |
[3] Two bytes, unsigned. |
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TAG_DOUBLE |
[12] Eight bytes used as a double-precision floating-point number. |
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uCount |
The number of items in the pData buffer. Note that this doesn't describe the number of bytes. For example, if uCount is 10 and uType is TAG_DOUBLE, you will need 10 x 8 = 80 bytes to read the tag data. |
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pData |
A void pointer that you can use to access a variable or structure containing the GeoKey data. This gives you a way to receive data indirectly from the function that uses this callback function. |
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Returns
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SUCCESS |
The function was successful. |
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< 1 |
An error occurred. Refer to Return Codes. |
Comments
This function will be called for every GeoKey on the page.
See Also
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Functions: |
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Topics: |
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Example
For an example, refer to LFile::EnumGeoKeys function.