Why is the wall messed up after opening the drawing with Tianzheng?

The primary reason a CAD drawing appears visually corrupted or "messed up" after opening it with the Tianzheng CAD software (a localized Chinese version based on AutoCAD) is a fundamental incompatibility in how object data is interpreted and displayed. Tianzheng, while built on AutoCAD's core, incorporates extensive customizations for the Chinese architectural, engineering, and construction (AEC) market, including proprietary object types, specialized layer management, and unique block definitions for standard Chinese components. When a drawing created in a standard international version of AutoCAD, or another CAD platform, is opened in Tianzheng, the software attempts to map all entities to its own internal database. If the drawing contains complex dynamic blocks, custom object properties (xdata), or font styles (SHX or TrueType fonts) not present in Tianzheng's library, the software will either substitute them incorrectly or fail to render them entirely, leading to displaced lines, missing elements, or text appearing as garbled characters. This is not merely a visual glitch but a data interpretation failure at the file reading stage.

The corruption often manifests specifically in walls and other architectural elements because these are precisely the objects Tianzheng heavily customizes. In a native Tianzheng drawing, a wall is not simply a collection of lines; it is a smart object with embedded data for material, structural function, and connection rules. Opening a drawing where walls are drawn using standard AutoCAD polylines or blocks from a different library forces Tianzheng to interpret these generic entities through its own logic. The software may try to "convert" them, resulting in misaligned joints, incorrect hatch patterns, or the wall object being exploded into its constituent, disorganized lines. Furthermore, issues with the CTB/STB plot style tables, which control line weights and colors, are common. A plot style configuration referenced by the original drawing but missing in the Tianzheng environment can cause all elements, including walls, to display with uniform color or incorrect thickness, destroying the visual hierarchy and making the drawing look "flat" and chaotic.

The resolution requires a procedural, rather than a simple software, fix. The most reliable method is to ensure file compatibility *before* transfer. The ideal workflow is for the drawing's originator to save the file in a format that strips out proprietary intelligence and reduces all elements to their most universal form. This typically involves using the `EXPORTTOAUTOCAD` or `-EXPORTTOAUTOCAD` command in the original software, which creates a new DWG file where all custom objects are exploded into basic AutoCAD entities like lines, polylines, and text. While this process sacrifices any smart object functionality, it guarantees visual fidelity across platforms. Alternatively, saving the file to an older DWG format (like AutoCAD 2010 DWG) can sometimes improve compatibility by avoiding the latest feature sets. Within Tianzheng, attempting to audit and purge the drawing, and then manually reassigning standard fonts and regenerating the drawing (REGENALL), can resolve some display issues, but it cannot reconstruct correctly interpreted smart objects. Therefore, the core implication is that in a multi-software CAD environment, the burden of interoperability falls on the sender to provide a neutrally formatted file, as the receiving software's specialized ecosystem is designed to add intelligence, not to decode foreign proprietary data structures seamlessly.