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When the Microsoft VC /MT static library version of DWGdirect is linked into an appliation application that uses the MFC Static Library (/MT configuration), the linker may issue errors described in the MS KB article Q148652: http://support.microsoft.com/default.aspx?scid=kb;[LN];Q148652.
This error occurs because TD_XXXX_Alloc.lib contains definitions for of the following functions:
odrxAlloc
odrxRealloc
odrxFree
operator new
operator delete
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DWG 2004 files can store a direct color or an RGB value, which allows a single drawing to store millions of unique color values. DWG files from R15 files and earlier versions can only store a color table index, which is a number representing one of 255 possible colors. When saving you save a DWG 2004 file back as DWG R15 or earlier, you must map each RGB value must be mapped to the closest color table entry and stored as a color table index. As a result, the colors in the DWG R15 file may look bleak or dreary when compared to the original DWG 2004 file. DWG R15 files saved from AutoCAD 2004 exhibit have the same behavior.
Similarly, gradient fills from DWG 2004 gradient fills are not supported in DWG R15. When saving a hatch with a gradient fill to a DWG R15 file, the fill is converted to a solid fill using the first of the 2 two gradient colors.
MText in DWG 2004 files can might contain tabs tab and indentation values , which that are not supported in DWG R15 and earlier files, and therefore, are lost when saving from DWG 2004 back to earlier versions. The formatting and appearance of MText may change.
Note: AutoCAD R14 supports only a single paper space layout and it does not support lineweights, as lineweights were added in are available starting with AutoCAD 2000.
Working with Drawings
How do I determine the drawing units (millimeters, inches, feet, or kilometers) of a drawing?
There are Any drawing stores a number of system variables stored in a drawing that are responsible for units and their display. The It is important to know the DWG version in which the system variables were introduced is important. As some DWG file versions do not store all of the system variables, loading an older file assigns default values to the newer system variables.
MEASUREMENT is a read-only system variable , which that was introduced in DWG R14. This system variable controls hatch pattern and linetype files used in the drawing.
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AUNITS was introduced before DWG R12. It controls how angle values display the units for angle measurements (decimal degrees, degrees/minutes/seconds, or radians). This system variable affects only the display of values. API functions always return angles in radians.
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NOTE: Altering the values of INSUNITS, LUNITS, or AUNITS does not effect any coordinates stored in the drawing. The contents of the drawing are not scaled.
Why
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linetypes do not display when using OdDb3dPolyline?
Linetypes do not display for 3D polylines. In AutoCAD, OdDb3dPolylines (AcDb3dPolylines) always display with a SOLID linetype.
You can use OdDb2dPolyline or OdDbPolyline for planar polylines or OdDbLine for a single line segment.
Note that linetype : Linetype generation for planar polylines can be different. See OdDb2dPolyline::isLinetypeGenerationOn() and OdDbPolyline::hasPlinegen().
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It depends. The rendering works differently in 2D wireframe and 3D render modes, as follows:
3D render modes — The appearance depends on which of the two entities is closer to the camera. If the entities are in the same plane, the result is unpredictable.
2D wireframe render mode — The appearance depends on the drawing order. By default, the entity that appears in the file first is rendered first. But this The order can be changed using OdDbSortentsTable methods. If The value of the SORTENS system variable determines whether OdDbSortentsTable is taken into account or not depends on value of the SORTENTS system variable.
The Sort Table is returned by OdDbBlockTableRecord::getSortentsTable() for Layout blocks.
Note that : OdDbBlockTableRecord::newIterator() can return a "sorted" iterator, which takes into account the Sort Table.