rotation2.java

基于j2me的任意角度图片旋转

package com.midp;

public class Rotation2 {
	/** 
	 * SIN TABLE 放大了255倍
	 */
	public final static int SIN_TABLE[] = {

	0, 4, 8, 13, 17, 22, 26, 31, 35, 39,

	44, 48, 53, 57, 61, 65, 70, 74, 78, 83,

	87, 91, 95, 99, 103, 107, 111, 115, 119, 123,

	127, 131, 135, 138, 142, 146, 149, 153, 156, 160,

	163, 167, 170, 173, 177, 180, 183, 186, 189, 192,

	195, 198, 200, 203, 206, 208, 211, 213, 216, 218,

	220, 223, 225, 227, 229, 231, 232, 234, 236, 238,

	239, 241, 242, 243, 245, 246, 247, 248, 249, 250,

	251, 251, 252, 253, 253, 254, 254, 254, 254, 254,

	255, 254, 254, 254, 254, 254, 253, 253, 252, 251,

	251, 250, 249, 248, 247, 246, 245, 243, 242, 241,

	239, 238, 236, 234, 232, 231, 229, 227, 225, 223,

	220, 218, 216, 213, 211, 208, 206, 203, 200, 198,

	195, 192, 189, 186, 183, 180, 177, 173, 170, 167,

	163, 160, 156, 153, 149, 146, 142, 138, 135, 131,

	127, 123, 119, 115, 111, 107, 103, 99, 95, 91,

	87, 83, 78, 74, 70, 65, 61, 57, 53, 48,

	44, 39, 35, 31, 26, 22, 17, 13, 8, 4,

	0, -4, -8, -13, -17, -22, -26, -31, -35, -39,

	-44, -48, -53, -57, -61, -65, -70, -74, -78, -83,

	-87, -91, -95, -99, -103, -107, -111, -115, -119, -123,

	-127, -131, -135, -138, -142, -146, -149, -153, -156, -160,

	-163, -167, -170, -173, -177, -180, -183, -186, -189, -192,

	-195, -198, -200, -203, -206, -208, -211, -213, -216, -218,

	-220, -223, -225, -227, -229, -231, -232, -234, -236, -238,

	-239, -241, -242, -243, -245, -246, -247, -248, -249, -250,

	-251, -251, -252, -253, -253, -254, -254, -254, -254, -254,

	-255, -254, -254, -254, -254, -254, -253, -253, -252, -251,

	-251, -250, -249, -248, -247, -246, -245, -243, -242, -241,

	-239, -238, -236, -234, -232, -231, -229, -227, -225, -223,

	-220, -218, -216, -213, -211, -208, -206, -203, -200, -198,

	-195, -192, -189, -186, -183, -180, -177, -173, -170, -167,

	-163, -160, -156, -153, -149, -146, -142, -138, -135, -131,

	-127, -123, -119, -115, -111, -107, -103, -99, -95, -91,

	-87, -83, -78, -74, -70, -65, -61, -57, -53, -48,

	-44, -39, -35, -31, -26, -22, -17, -13, -8, -4

	};

	public static int TRANSPARENT = 0;
	
	public static int getRadius(int _width,int _height)
	{
		return (int)Math.sqrt(_width*_width + _height*_height);
	}
	
	public static int[] rotate(int[] _pixels,int _width,int _height,int _angle)
	{
		int i,j;
		int r = getRadius(_width,_height);
		int[] newPixels = new int[r*r];
		for(i = 0; i < newPixels.length;i++)
		{
				newPixels[i] = (TRANSPARENT)<<24;
		}
		int w = _width<<16;
		int h = _height<<16;
		int x,y;
		int tmp_sin = SIN_TABLE[_angle%360]<<8;
		int tmp_cos = SIN_TABLE[(_angle + 90) % 360]<<8;
		for(i = 0;i < r;i++)
		{
			x = (-r/2)*tmp_cos + (i - r/2)*tmp_sin;
			y = (r/2)*tmp_sin + (i - r/2)*tmp_cos;
			for(j = 0;j < r;j++)
			{
				if(x >= -w/2&&x< w/2&&y >= -h/2&&y< h/2)
				{
					int k = ((y>>16)+_height/2)*_width+(x>>16)+_width/2;
					newPixels[i*r + j] = _pixels[k];
				}
				x += tmp_cos;
				y -= tmp_sin;
			}
		}
		return newPixels;
	}

}