<html> <head> <style></style> </head> <body class='hmmessage'> Dear all:     I first convert DWG files to JPG files,then to X11 bitmap files by GIMP software for using with the click-on bitmap facility to create ground topography surfaces associating with a model.But now new problem came.I selected the floor plan extrusion input mode,set the floor elevation to 0.0 and the ceiling elevation to 4.5,then started to define points from the bitmap image to build zones in sequence by selecting the create another zone option after finishing the zone before.When I have finished the last zone and exit from the click-on facility,instead of being presented with a wireframe view of the zones I have created,I can only see the last zone and then was reminded that "FAILURE:.../...geo:0  0  0.000 the no of vertices value(0) < allowable minimum 4!the no of surfaces value(0) < allowable minimum 3".How frustrated！     Any answer is appreciated!Thank you very much! <hr />搜索本应是彩色的,快来体验新一代搜索引擎-必应,精美图片每天换哦! <a href='http://cn.bing.com/?form=CRMADS ' target='_new'>立即试用！</a></body> </html>