在窗口实时显示屏幕内容，可作为LED大屏显示用

透视投影为三维图形显示的基础，在此基础上提出了一种基于透视投影矩阵的数学模型．可方便地将空间三维坐标转换为透视投影坐标，并实时地在屏幕上展现出来．并以三维数据的透视投影为例，显示了经过该透视变换后的透视图，验证了该方法的有效性．-Perspective projection of three-dimensional graphics based on this based on the perspective projection matrix based on a mathematical m

该功能主要实现实时截取当前屏幕并保存为bmp格式的图片到当前程序运行的路径底下。用户只要点击对话框上的按钮，就能在相应路径底下查看图片。-The main functions to realize real-time capture the current screen and saved as a BMP format pictures under the path to the current program is running. Users just click on the butto