关于游戏中高效的换色方法

     首先，我们取得png图片的二进制数据，修改其中的调色板域(PLTE chunk)数据，再使用createImage(byte[] imageData,int imageOffset,int imageLength)将修改后的二进制数据生成新的png对象。（换色是基于对图像格式的熟悉来进行的，所以你必须先了解PNG图片的格式，这个可以参考http://www.w3.org/TR/PNG/）

下面是获得图片调色板数据的方法（感谢飘飘白云的代码）

             /**
               * 修改png图片的调色板数据生成新的png图片
               * @param imageSrc png图片的二进制数据字节数组
               * @return 修改后的png图片
               */
              public Image getPLTEModifidImage(byte[] imageSrc)
              {
                            if (imageSrc == null imageSrc.length <= 1)
                                          return null;
 
                            if (crcTable == null)
                                          makeCrcTable();
 
                            // PLTE chunk数据域的类型标识
                            // see http://www.w3.org/TR/PNG/#11PLTE
                            String[] sPLTE = {"50", "4c", "54", "45"};
 
                            int i,j;
                            int pos = 0,startPos = 0;
                            byte[] data = imageSrc;
                           
                            for (i = 0; i < data.length; i++)
                            {
                        if (Integer.toHexString(data[i]).equals(sPLTE[0])
                                                  && Integer.toHexString(data[i + 1]).equals(sPLTE[1])
                                                  && Integer.toHexString(data[i + 2]).equals(sPLTE[2])
                    && Integer.toHexString(data[i + 3]).equals(sPLTE[3]))
                        {
                                      pos = i;
                                      break;
                        }
                            }
                            pos -= 4;
                            startPos = pos;