使用透视变换的图像变换

先生

我正在借助反纹理几何API在Visual C ++中从事图像转换项目的工作

http://www.antigrain.com/ [ ^ ]

在此链接上有一个api，在示例文件夹中的该api中，我得到了image_perspective转换.
它是四点变换，因此我能够拉伸拐角处的图像，因为map_matrix只能使用4点.
现在我要从4点拉伸图像，这是图像四个边缘的中点.以及从图像的中心点开始.

请让我知道如何在转换中添加4个以上的点

sir

i m working on the image transformation project in visual c++ with the help of anti grain geometry api

http://www.antigrain.com/[^]

on this link there is api and in that api in example folder i got image_perspective transform.
it is four point transform so i am able to strech image using for corners as map_matrix can take only 4 points.
now i want to strech image from the 4 point wich are the mid point of four edges of image. as well as from the centre point of image.

plz let me know how to add more than 4 point in transformation