gdi32: Use documented structure layout for EMF-to-WMF embedding records.

dlls/gdi32/enhmetafile.c

@@ -2804,7 +2804,7 @@ static HENHMETAFILE extract_emf_from_comment( const BYTE *buf, UINT mf_size )
         chunk = (emf_in_wmf_comment *)(mr->rdParm + 2);
 
         if (mr->rdFunction != META_ESCAPE || mr->rdParm[0] != MFCOMMENT) goto done;
-        if (chunk->magic != WMFC_MAGIC) goto done;
+        if (chunk->comment_id != WMFC_MAGIC) goto done;
 
         if (!emf_bits)
         {

dlls/gdi32/metafile.c

@@ -1096,13 +1096,11 @@ static BOOL add_mf_comment(HDC hdc, HENHMETAFILE emf)
     chunk = HeapAlloc(GetProcessHeap(), 0, FIELD_OFFSET(emf_in_wmf_comment, emf_data[max_chunk_size]));
     if(!chunk) goto end;
 
-    chunk->magic = WMFC_MAGIC;
-    chunk->unk04 = 1;
-    chunk->unk06 = 0;
-    chunk->unk08 = 0;
-    chunk->unk0a = 1;
+    chunk->comment_id = WMFC_MAGIC;
+    chunk->comment_type = 0x1;
+    chunk->version = 0x00010000;
     chunk->checksum = 0; /* We fixup the first chunk's checksum before returning from GetWinMetaFileBits */
-    chunk->unk0e = 0;
+    chunk->flags = 0;
     chunk->num_chunks = (size + max_chunk_size - 1) / max_chunk_size;
     chunk->chunk_size = max_chunk_size;
     chunk->remaining_size = size;

dlls/gdi32/ntgdi_private.h

@@ -462,13 +462,11 @@ extern HMETAFILE MF_Create_HMETAFILE(METAHEADER *mh) DECLSPEC_HIDDEN;
 #include <pshpack2.h>
 typedef struct
 {
-    DWORD magic;   /* WMFC */
-    WORD unk04;    /* 1 */
-    WORD unk06;    /* 0 */
-    WORD unk08;    /* 0 */
-    WORD unk0a;    /* 1 */
+    DWORD comment_id;   /* WMFC */
+    DWORD comment_type; /* Always 0x00000001 */
+    DWORD version;      /* Always 0x00010000 */
     WORD checksum;
-    DWORD unk0e;   /* 0 */
+    DWORD flags;        /* Always 0 */
     DWORD num_chunks;
     DWORD chunk_size;
     DWORD remaining_size;