两个AABB的相交性检测
检测两个静止AABB的相交性是很简单的，只需要在每一维上单独检查它们的重合程度即可。如果在所有维上都没有重合，那么这两个AABB就不会相交。intersectAABBs()就是用这项技术来实现的。
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//--------------------------------------------------------------------------- |
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// Check if two AABBs intersect, and return true if so. Optionally return |
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// the AABB of their intersection if an intersection is detected. |
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//--------------------------------------------------------------------------- |
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bool intersectAABBs(const AABB3& box1, const AABB3& box2, AABB3* boxIntersect) |
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{ |
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// Check for no overlap |
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if (box1.min.x > box2.max.x) return false; |
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if (box1.max.x < box2.min.x) return false; |
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if (box1.min.y > box2.max.y) return false; |
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if (box1.max.y < box2.min.y) return false; |
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if (box1.min.z > box2.max.z) return false; |
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if (box1.max.z < box2.min.z) return false; |
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|
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// We have overlap. Compute AABB of intersection, if they want it. |
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if (boxIntersect != NULL) |
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{ |
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boxIntersect->min.x = max(box1.min.x, box2.min.x); |
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boxIntersect->max.x = min(box1.max.x, box2.max.x); |
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boxIntersect->min.y = max(box1.min.y, box2.min.y); |
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boxIntersect->max.y = min(box1.max.y, box2.max.y); |
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boxIntersect->min.z = max(box1.min.z, box2.min.z); |
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boxIntersect->max.z = min(box1.max.z, box2.max.z); |
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} |
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|
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return true; |
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