Question

我尝试实现一个相机类。其中一种模式应该是基本的FPS摄像机行为，当你可以用鼠标改变方向，左右扫描并向前/向后移动时向前/向后移动。我有以下代码，它似乎在开始时工作正常，但随后方向向量被破坏：

我的想法是我不存储当前方向的角度，而是将glutPassiveMotionFunc()上的每个像素的前向矢量（我已经有）旋转1-2度：



void Camera::Control(int x, int y)
{
    switch (mode) {
        case AVATAR:
            if (x < prevX) direction.Rotate(1. * (prevX - x), up.Inverted());
            if (x > prevX) direction.Rotate(1. * (x - prevX), up);
            if (y < prevY) direction.Rotate(1. * (prevY - y), direction % up);
            if (y > prevY) direction.Rotate(1. * (y - prevY), up % direction);
            direction.Normalize();
            //up = (direction % up) % direction; //UP in vitual space or for the camera?
            prevX = x;
            prevY = y;
            //Debug vector values:
            //printf("\nwinX: %d\twinY: %d\n", x, y);
            //printf("radX: %0.3f\tradY: %0.3f\n", x, y);
            //printf("dirX: %0.3f\ndirY: %0.3f\ndirZ: %0.3f\n", direction.X, direction.Y, direction.Z);
            //printf("posX: %0.3f\nposY: %0.3f\nposZ: %0.3f\n", position.X, position.Y, position.Z);
            break;
        case ORBIT: /* ... */ break;
        default: break;
    }
}

void Camera::Control(int x, int y) { switch (mode) { case AVATAR: if (x < prevX) direction.Rotate(1. * (prevX - x), up.Inverted()); if (x > prevX) direction.Rotate(1. * (x - prevX), up); if (y < prevY) direction.Rotate(1. * (prevY - y), direction % up); if (y > prevY) direction.Rotate(1. * (y - prevY), up % direction); direction.Normalize(); //up = (direction % up) % direction; //UP in vitual space or for the camera? prevX = x; prevY = y; //Debug vector values: //printf("\nwinX: %d\twinY: %d\n", x, y); //printf("radX: %0.3f\tradY: %0.3f\n", x, y); //printf("dirX: %0.3f\ndirY: %0.3f\ndirZ: %0.3f\n", direction.X, direction.Y, direction.Z); //printf("posX: %0.3f\nposY: %0.3f\nposZ: %0.3f\n", position.X, position.Y, position.Z); break; case ORBIT: /* ... */ break; default: break; } }
Strafe效果很好：

void Camera::Control(int key)
{
    switch (key) {
        case 'w': position += direction.Normal(); break;
        case 's': position -= direction.Normal(); break;
        case 'a': position += (up % direction).Normal(); break;
        case 'd': position += (direction % up).Normal(); break;
        default: break;
    }
}

相机如何刷新其视图：

void Camera::Control(int key)
{
    switch (key) {
        case 'w': position += direction.Normal(); break;
        case 's': position -= direction.Normal(); break;
        case 'a': position += (up % direction).Normal(); break;
        case 'd': position += (direction % up).Normal(); break;
        default: break;
    }
}

向量的旋转：

void Camera::Draw()
{
    gluLookAt(position.X, position.Y, position.Z, position.X + direction.X, position.Y + direction.Y, position.Z + direction.Z, up.X, up.Y, up.Z);
}

void Camera::Draw()
{
    gluLookAt(position.X, position.Y, position.Z, position.X + direction.X, position.Y + direction.Y, position.Z + direction.Z, up.X, up.Y, up.Z);
}

当我测试旋转功能并且整个概念仅在X轴上旋转时，它工作正常。我可以看看向量（Y轴）。仅围绕（方向％向上）和（向上％方向）旋转也有效。（

void Vector::Rotate(float angle, float x, float y, float z)
{
    float rad = angle * PI / 180.;
    float s = sin(rad), c = cos(rad);
    float matrix[9] = {
        x*x*(1-c)+c,    y*x*(1-c)-s*z,  z*x*(1-c)+s*y,
        x*y*(1-c)+s*z,  y*y*(1-c)+c,    z*y*(1-c)+s*x,
        x*z*(1-c)-s*y,  y*z*(1-c)+s*x,  z*z*(1-c)+c
    };
    *this = Vector(X * matrix[0] + Y * matrix[3] + Z * matrix[6], X * matrix[1] + Y * matrix[4] + Z * matrix[7], X * matrix[2] + Y * matrix[5] + Z * matrix[8]);
}

void Vector::Rotate(float angle, Vector& axis)
{
    Rotate(angle, axis.X, axis.Y, axis.Z);
}

定义了交叉乘积。）当我计算X和Y位置的旋转时会出现问题。有什么想法吗？

Answer 1

计算方向％向上并在应用Y旋转之前对结果进行标准化。

FPS相机实现错误（OpenGL / GLUT / C ++）

1 个答案: