Question

我有一个简单的设置，它有一个球在屏幕周围弹跳，我希望能够给出它不能在里面移动的物体（它们将充当障碍物）。目前有以下逻辑尝试实现此目的。

void AnimatableObject::ExcludeRects(AnimatableObject *obj) {
        for (int i = 0; i < obj->numberOfExclusionBounds; i++) {
            SDL_Rect bounds = obj->exclusionBounds[i];

            /* TOUCHING SIDES OF THE RECT*/
            bool touchingTopOfRect = obj->m_dY + obj->m_dHeight > bounds.y &&
                obj->m_dY < bounds.y + bounds.h &&
                obj->m_dX > bounds.x &&
                obj->m_dX + obj->m_dWidth < bounds.x + bounds.w;

            bool touchingBottomOfRect = obj->m_dY < bounds.y + bounds.h &&
                obj->m_dY > bounds.y &&
                obj->m_dX > bounds.x &&
                obj->m_dX + obj->m_dWidth < bounds.x + bounds.w;

            bool touchingRightOfRect = obj->m_dX < bounds.x + bounds.w &&
                obj->m_dX > bounds.x &&
                obj->m_dY > bounds.y &&
                obj->m_dY + obj->m_dHeight < bounds.y + bounds.h;

            bool touchingLeftOfRect = obj->m_dX + obj->m_dWidth > bounds.x &&
                obj->m_dX + obj->m_dWidth < bounds.x + bounds.w &&
                obj->m_dY > bounds.y &&
                obj->m_dY + obj->m_dHeight > bounds.y + bounds.h;


            // Top of a rect.
            if (touchingTopOfRect) {
                obj->m_dY = bounds.y - obj->m_dHeight;
                obj->bottomContact = true;
            }

            // Bottom of Rect
            if (touchingBottomOfRect) {
                obj->m_dY = bounds.y + bounds.h;
                obj->topContact = true;
            }

            // Left Side of rect.
            if (touchingLeftOfRect) {
                obj->m_dX = bounds.x - obj->m_dWidth;
                obj->rightContact = true;
            }

            // Right Side of rect
            if (touchingRightOfRect) {
                printf("HIT RIGHT OF A OBSTACLE %d\n", bounds.w);

                obj->m_dX = bounds.x + bounds.w;
                obj->leftContact = true;
            }
        }
}

因此，每个帧都会调用它，并将循环存储我想要从对象可移动区域中排除的rects的数组。

使用这种方法开始工作变得非常棘手，很多时候条件会在他们不应该的时候开始。然而，我的主要问题是这对我来说似乎不必要地复杂化。有没有更好的方法来解决这个问题？

Answer 1

您应该可以使用SDL_HasIntersection

进行大致简单的操作

基本伪代码将与

一致

for each collider rect
  if HasIntersection( bounds, colliderBounds )
    find the centre points of each rect (x+w/2, y+h/2)
    bool touchingLeft = ( bounds_centre.x < collider_centre.x )
    bool touchingRight = ( bounds_cenre.x > collider_centre.x )
    ... etc ...

见

http://wiki.libsdl.org/SDL_HasIntersection

编辑：另一种选择是自己跳过任何碰撞检测，并使用优秀的Box2D代替：

http://box2d.org/

从游戏中的可移动空间移除rects

1 个答案: