コード例 #1
0
int Collision::RectVsCircle(RECT rect, float xO, float yO, float R)
{
    //AB
    //CD
    //Hình chữ nhật ABCD, đường tròn tâm O, bán kính R
    //Tìm điểm M, là điểm gần O nhất
    float xM, yM, xA, yA, xB, yB, xC, yC, xD, yD;
    xA=xD=rect.left;
    xB=xC=rect.right;
    yA=yB=rect.top;
    yC=yD=rect.bottom;

    xM = MiddleNumber(xA, xO, xC);       //Tìm tọa độ M
    yM = MiddleNumber(yA, yO, yC);
    if (Distance(xM,yM,xO,yO) < R)            //Xảy ra va chạm
    {
        if (PointInLine(xM,yM,xA,yA,xB,yB)==0)                  //Nếu M nằm trên AB
        {
            if (PointInLine(xM,yM, xB, yB, xC, yC)==0) return 6;    //Va chạm tại B
            if(PointInLine(xM,yM,xA,yA,xD,yD)==0)return 5;        //Va chạm tại A
            else return 1;                         //Va chạm tại AB
        }
        if(PointInLine(xM,yM,xC,yC,xD,yD)==0)
        {
            if(PointInLine(xM,yM,xB,yB,xC,yC)==0)return 7;          //C
            if (PointInLine(xM,yM, xA, yA, xD,yD)==0) return 8;      //D
            else return 3;                              //CD
        }
        if (PointInLine(xM,yM, xB,yB, xC,yC)==0) return 2;          //BC
        if (PointInLine(xM,yM, xD,yD, xA,yA) == 0) return 4;
        else return 9;                              //Nằm trọn trong ABCD
    }
    else return 0;
}
コード例 #2
0
// Checks if a line intersect with another line
// inout    Line : another line
//          Marge: optional, standard on MARGE (declared in MISC.CPP)
//
// return true : lines are crossing
//    false: lines are not crossing
//
int kbLine::CheckIntersect ( kbLine * lijn, double Marge )
{
    double distance = 0;
    // link must exist
    assert( m_link );
    // lijn must exist
    assert( lijn );

    // points may not be equal
    // must be an if statement because if an assert is used there will
    // be a macro expansion error
    if ( m_link->GetBeginNode() == m_link->GetEndNode() )
        assert( !m_link );

    int Take_Action1, Take_Action2, Total_Result;
    kbNode *bp, *ep;
    PointStatus Result_beginnode, Result_endnode;

    bp = lijn->m_link->GetBeginNode();
    ep = lijn->m_link->GetEndNode();
    Result_beginnode = PointInLine( bp, distance, Marge );
    Result_endnode   = PointInLine( ep, distance, Marge );
    Take_Action1 = ActionOnTable1( Result_beginnode, Result_endnode );
    switch ( Take_Action1 )
    {
        case 0: Total_Result = false ; break;
        case 1:
        {
            bp = m_link->GetBeginNode();
            ep = m_link->GetEndNode();
            Result_beginnode = lijn->PointInLine( bp, distance, Marge );
            Result_endnode   = lijn->PointInLine( ep, distance, Marge );
            Take_Action2 = ActionOnTable2( Result_beginnode, Result_endnode );
            switch ( Take_Action2 )
            {
                case 0: Total_Result = false; break;
                case 1: case 2: case 3: case 4: Total_Result = true; break;
                default: Total_Result = false; assert( Total_Result );
            }
        }
        ; break; // This break belongs to the switch(Take_Action1)
        case 2: case 3: case 4: case 5: case 6: Total_Result = true; break;
        default: Total_Result = false; assert( Total_Result );
    }
    return Total_Result; //This is the final decision
}
コード例 #3
0
// Intersects two lines
// input    Line : another line
//          Marge: optional, standard on MARGE
//
// return 0: If there are no crossings
//    1: If there is one crossing
//    2: If there are two crossings
int kbLine::Intersect( kbLine * lijn, double Marge )
{
    double distance = 0;
    // lijn must exist
    assert( lijn );

    // points may not be equal
    // must be an if statement because if an assert is used there will
    // be a macro expansion error
    if ( m_link->GetBeginNode() == m_link->GetEndNode() )
        assert( !m_link );

    kbNode *bp, *ep;
    PointStatus Result_beginnode, Result_endnode;
    int Take_Action1, Take_Action2, Number_of_Crossings = 0;

    // Get the nodes from lijn via the link
    bp = lijn->m_link->GetBeginNode();
    ep = lijn->m_link->GetEndNode();

    Result_beginnode = PointInLine( bp, distance, Marge );
    Result_endnode   = PointInLine( ep, distance, Marge );

    Take_Action1 = ActionOnTable1( Result_beginnode, Result_endnode );

    // The first switch will insert a crosspoint immediatly
    switch ( Take_Action1 )
    {
            // for the cases see the returnvalue of ActionTable1
    case 2: case 6: AddCrossing( ep );
            Number_of_Crossings = 1;
            break;
    case 3: case 5: AddCrossing( bp );
            Number_of_Crossings = 1;
            break;
        case 4:     AddCrossing( bp );
            AddCrossing( ep );
            Number_of_Crossings = 2;
            break;
    }
    // This switch wil investigate the points of this line in relation to lijn
    switch ( Take_Action1 )
    {
            // for the cases see the returnvalue of ActionTable1
case 1: case 5: case 6:
        {
            // Get the nodes from this line via the link
            bp = m_link->GetBeginNode();
            ep = m_link->GetEndNode();
            Result_beginnode = lijn->PointInLine( bp, distance, Marge );
            Result_endnode   = lijn->PointInLine( ep, distance, Marge );
            Take_Action2 = ActionOnTable2( Result_beginnode, Result_endnode );
            switch ( Take_Action2 )
            {
                    // for the cases see the returnvalue of ActionTable2
                case 1:
                {   // begin of scope to calculate the intersection
                    double X, Y, Denominator;
                    CalculateLineParameters();
                    Denominator  = ( m_AA * lijn->m_BB ) - ( lijn->m_AA * m_BB );
                    // Denominator may not be 0
                    assert( Denominator != 0.0 );
                    // Calculate intersection of both linesegments
                    X = ( ( m_BB * lijn->m_CC ) - ( lijn->m_BB * m_CC ) ) / Denominator;
                    Y = ( ( lijn->m_AA * m_CC ) - ( m_AA * lijn->m_CC ) ) / Denominator;

                    //make a decent rounding to B_INT
                    AddLineCrossing( ( B_INT )X, ( B_INT )Y, lijn );
                }   // end of scope to calculate the intersection
                Number_of_Crossings++;
                break;
                case 2: lijn->AddCrossing( ep );
                    Number_of_Crossings++;
                    break;
                case 3: lijn->AddCrossing( bp );
                    Number_of_Crossings++;
                    break;
                case 4: lijn->AddCrossing( bp );
                    lijn->AddCrossing( ep );
                    Number_of_Crossings = 2;
                    break;
            }
        }
        ; break; // This break belongs to the outer switch
    }
    return Number_of_Crossings; //This is de final number of crossings
}