sinecosine.java

来自「这个游戏的关卡使用mapwin制作的」· Java 代码 · 共 79 行

/**
 * 非作者授权，请勿用于商业用途。
 * @author  [e-mail]
 * sin cos　表格求法
 * */
public class Sinecosine {
    static short sineTable[] = {
        0, 4, 9, 13, 18, 22, 27, 31, 36, 40,
        44, 49, 53, 58, 62, 66, 71, 75, 79, 83,
        88, 92, 96, 100, 104, 108, 112, 116, 120, 124,
        128, 132, 136, 139, 143, 147, 150, 154, 158, 161,
        165, 168, 171, 175, 178, 181, 184, 187, 190, 193,
        196, 199, 202, 204, 207, 210, 212, 215, 217, 219,
        222, 224, 226, 228, 230, 232, 234, 236, 237, 239,
        241, 242, 243, 245, 246, 247, 248, 249, 250, 251,
        252, 253, 254, 254, 255, 255, 255, 1, 1, 1,
        1
    };

    static int sinFP(int angle) {
        int sin;
        if (angle <= 90) {
            sin = sineTable[angle];
            if (sin == 1) {
                sin = 256;
            }
        }
        else if (angle <= 180) {
            sin = sineTable[180 - angle];
            if (sin == 1) {
                sin = 256;
            }
        }
        else if (angle <= 270) {
            sin = -sineTable[angle - 180];
            if (sin == -1) {
                sin = -256;
            }
        }
        else { /* angle <= 360 */
            sin = -sineTable[360 - angle];
            if (sin == -1) {
                sin = -256;
            }
        }
        return sin;
    }

    static int cosFP(int angle) {
        int cos;
        if (angle <= 90) {
            cos = sineTable[90 - angle];
            if (cos == 1) {
                cos = 256;
            }
        }
        else if (angle <= 180) {
            cos = -sineTable[angle - 90];
            if (cos == -1) {
                cos = -256;
            }
        }
        else if (angle <= 270) {
            cos = -sineTable[270 - angle];
            if (cos == -1) {
                cos = -256;
            }
        }
        else { /* angle <= 360 */
            cos = sineTable[angle - 270];
            if (cos == 1) {
                cos = 256;
            }
        }
        return cos;
    }

}