Handling collisions

// This function takes two 2d axis-aligned boxes in min-max form, and returns// a boolean result indicating whether they are intersecting. If they are,// the vector 'resolve' is set so that adding it to the position of the first// of the two boxes will resolve the intersection. This is based on the// assumption that the first box is a character (or other moving object) and// the second is an imobile obstacle. (You can also treat both objects as// moving by moving each by half of the resolve vector in opposite// directions.)// Note that this test is for relatively slow-moving objects that won't pass// through each other or intersect too deeply in one timestep. For most// types of game characters, this is a reasonable assumption; otherwise, a// more complicated swept test may be required.bool IntersectBoxes(    Vector2  min0,    Vector2  max0,    Vector2  min1,    Vector2  max1,    Vector2& resolve){    float diff,minDiff;    int axis,side;        // Left    diff = max0[0]-min1[0];    if (diff < 0.0f) {        return false;    }    minDiff = diff;    axis = 0;    side = -1;        // Right    diff = max1[0]-min0[0];    if (diff < 0.0f) {        return false;    }    if (diff < minDiff) {        minDiff = diff;        side = 1;    }        // Down    diff = max0[1]-min1[1];    if (diff < 0.0f) {        return false;    }    if (diff < minDiff) {        minDiff = diff;        axis = 1;        side = -1;    }        // Up    diff = max1[1]-min0[1];    if (diff < 0.0f) {        return false;    }    if (diff < minDiff) {        minDiff = diff; // [Edit: This line was missing]        axis = 1;        side = 1;    }        // Intersection occurred    resolve.Zero(); // Zero() just sets all components to 0    resolve[axis] = (float)side*minDiff;    return true;}