投影projection 投影中心centerofprojection 投影面projectingplane 投影线projectingline 中心投影法perspectiveprojection 平行投影法parallelprojection 斜投影obliqueprojection 正投影orthographicprojection 正投影面frontalplaneofprojection 侧面投影面profileplaneofprojection 投影图projectiondrawing 三面投影图three-planeprojectiondrawing 投影轴 axisofprojection 投影特性 characteristicofprojection 不变性 characteristicoftrue 积聚性 characteristicofconcentration 类似性 characteristicofsimilarity 视图view 三视图three-viewdrawing 正面frontalplane 正面投影frontalprojection 水平面horizontalplane 水平投影horizontalprojection 侧面profileplane 侧面投影profileprojection 主视图frontalview 俯视图topview 左视图leftsideview 立体 solid 平面立体 planebody 曲面立体 bodyofcurvedsurface 回转面surfaceofrevolution 棱柱 prism 棱锥 pyramid 边 side 顶点 centervertex 棱 edge 点 point 直线linestraightline 棱锥台 truncatedpyramid frustumofpyram