graph transformation from window to viewport 窗口到视口的直观匹配变换
Using attributed graph transformation productions defined on wscg model, the consistency between wscg execution instance and wscg model is guaranteed with a sound formal semantic basis wscg模型的执行语义有两种描述方式,一种是定义在wscg元模型之上的基本的执行语义,这是wscg模型进行解释执行的基础。