IsoAlgo --- Symbol Template and its Projectioneryar@163.comKey words: Isometric Piping Symbol, Isometric Projection, Isometric Symbol Template
在管路轴测图中,除了管子以外,其他部件都是以一个符号表示,而不是三维模型中的实体模型的比例投影。符号通过SKEY来区别。为了对符号的统一处理,可以使用符号模板来简化。即每个符号都包含以下几部分:
Figure 1 Piping Symbol Template
符号在模板中都是在正交的二维坐标系中,通过坐标系变换,将符号可以画在任意坐标系中。以下以一个法兰的符号为例来说明。下图所示为一个法兰的符号模板:
Figure 2 Flange Symbol
通过坐标系变换,可以将直角坐标系的符号模板转换为所需要的坐标系中。如下图所示为将法兰符号模板变换坐标系后的图形:
Figure 3 Flange in SouthWest isometric projection plane made by u Axis and v Axis
Figure 4 Flange in SouthWest isometric projection plane made by v Axis and u Axis
Figure 5 Flange in SouthWest isometric projection plane made by w Axis and u Axis
解决符号模板的轴测投影问题后,仍然有其他问题需要确定。如下图所示为一管路的三维模型:
Figure 6 Piping 3D Model in AutoCAD Plant 3D
Figure 7 Piping Isometric Drawing Generated by IsoAlgo
Figure 8 Piping Isometric Drawing Generated by IsoAlgo in OpenSceneGraph
由上图可知,虽然符号模板的投影问题解决了,但是还存在符号投影后的连接问题及方向问题。如上图中右上角的法兰与容器相连,
法兰应与图中方向相反才是正确的方向。处理好这些问题后,就可以专心来做无比例化。