【计算机图形学】实验三 用Cohen-Sutherland裁剪算法实现直线段裁剪

int computeOutCode(int x, int y, int xmin, int xmax, int ymin, int ymax) {
    int code = INSIDE;

    if (x < xmin)
        code |= LEFT;
    else if (x > xmax)
        code |= RIGHT;

    if (y < ymin)
        code |= BOTTOM;
    else if (y > ymax)
        code |= TOP;

    return code;
}

void cohenSutherland(int x0, int y0, int x1, int y1, int xmin, int xmax, int ymin, int ymax) {
    int outcode0 = computeOutCode(x0, y0, xmin, xmax, ymin, ymax);
    int outcode1 = computeOutCode(x1, y1, xmin, xmax, ymin, ymax);
    bool accept = false;

    while (true) {
        if ((outcode0 | outcode1) == 0) {
            accept = true;
            break;
        }
        else if ((outcode0 & outcode1) != 0) {
            break;
        }
        else {
            int x, y;
            int outcodeOut = outcode0 != 0 ? outcode0 : outcode1;

            if (outcodeOut & TOP) {
                x = x0 + (x1 - x0) * (ymax - y0) / (y1 - y0);
                y = ymax;
            }
            else if (outcodeOut & BOTTOM) {
                x = x0 + (x1 - x0) * (ymin - y0) / (y1 - y0);
                y = ymin;
            }
            else if (outcodeOut & RIGHT) {
                y = y0 + (y1 - y0) * (xmax - x0) / (x1 - x0);
                x = xmax;
            }
            else if (outcodeOut & LEFT) {
                y = y0 + (y1 - y0) * (xmin - x0) / (x1 - x0);
                x = xmin;
            }

            if (outcodeOut == outcode0) {
                x0 = x;
                y0 = y;
                outcode0 = computeOutCode(x0, y0, xmin, xmax, ymin, ymax);
            }
            else {
                x1 = x;
                y1 = y;
                outcode1 = computeOutCode(x1, y1, xmin, xmax, ymin, ymax);
            }
        }
    }

    if (accept) {
        printf("裁剪后的直线段坐标为：(%d, %d) 到 (%d, %d)\n", x0, y0, x1, y1);
    }
    else {
        printf("直线段在窗口外部，不进行裁剪。\n");
    }
}