fix: EMRTEXT wire layout — ptlReference is POINTL not WmfRect16 - #6
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After studying libemf2svg's emf2svg_rec_drawing.c and the U_EMRTEXT struct in libUEMF, discovered the wire layout was wrong. Previous (incorrect): int16 wmf_rect_left/top/right/bottom (WmfRect16, 8 bytes) Correct (per MS-EMF 2.2.6 EMRTEXT): point_l ptl_reference (POINTL, 8 bytes — int32 x, int32 y) uint32 n_chars uint32 off_string uint32 f_options rectl rcl (RECTL, 16 bytes — clipping rectangle) uint32 off_dx The ptlReference is the text anchor point — the most critical field for text positioning. Was previously parsed as 4 int16 values (wmf_rect_left/top/right/bottom) which mapped to the wrong bytes, causing all text to be positioned at incorrect coordinates. Round-trip verified: 208/208 byte-identical.
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Critical wire layout fix discovered by studying libemf2svg's U_EMRTEXT struct definition. ptlReference (POINTL: two int32) was being parsed as WmfRect16 (four int16). Text positions were completely wrong.
Companion to emfsvg PR that takes advantage of this fix to reach 81.1% byte ratio vs libemf2svg.
Round-trip: 208/208 byte-identical.