说明：  发现不用perlin noise随便找个位图读每点的像素的RGB,然后将R+B+G作为地形高度也可.我可以尽量将位图颜色过渡做的平缓些,出来的地形还是尖锐.
(perlin noise found not arbitrarily find a bitmap read every point of the pixel RGB, then R B G as the terrain is available. I can try to color bitmap smooth transition done more, the terrain is sharp.)