C++ QwtInterval::contains方法代码示例

/*!
   \return the value at a raster position

   \param x X value in plot coordinates
   \param y Y value in plot coordinates

   \sa ResampleMode
*/
double QwtMatrixRasterData::value( double x, double y ) const
{
    const QwtInterval xInterval = interval( Qt::XAxis );
    const QwtInterval yInterval = interval( Qt::YAxis );

    if ( !( xInterval.contains(x) && yInterval.contains(y) ) )
        return qQNaN();

    double value;

    switch( d_data->resampleMode )
    {
        case BilinearInterpolation:
        {
            int col1 = qRound( (x - xInterval.minValue() ) / d_data->dx ) - 1;
            int row1 = qRound( (y - yInterval.minValue() ) / d_data->dy ) - 1;
            int col2 = col1 + 1;
            int row2 = row1 + 1;

            if ( col1 < 0 )
                col1 = col2;
            else if ( col2 >= static_cast<int>( d_data->numColumns ) )
                col2 = col1;

            if ( row1 < 0 )
                row1 = row2;
            else if ( row2 >= static_cast<int>( d_data->numRows ) )
                row2 = row1;

            const double v11 = d_data->value( row1, col1 );
            const double v21 = d_data->value( row1, col2 );
            const double v12 = d_data->value( row2, col1 );
            const double v22 = d_data->value( row2, col2 );

            const double x2 = xInterval.minValue() + 
                ( col2 + 0.5 ) * d_data->dx;
            const double y2 = yInterval.minValue() + 
                ( row2 + 0.5 ) * d_data->dy;
                
            const double rx = ( x2 - x ) / d_data->dx;
            const double ry = ( y2 - y ) / d_data->dy;

            const double vr1 = rx * v11 + ( 1.0 - rx ) * v21;
            const double vr2 = rx * v12 + ( 1.0 - rx ) * v22;

            value = ry * vr1 + ( 1.0 - ry ) * vr2;

            break;
        }
        case NearestNeighbour:
        default:
        {
            int row = int( (y - yInterval.minValue() ) / d_data->dy );
            int col = int( (x - xInterval.minValue() ) / d_data->dx );

            // In case of intervals, where the maximum is included
            // we get out of bound for row/col, when the value for the
            // maximum is requested. Instead we return the value
            // from the last row/col

            if ( row >= d_data->numRows )
                row = d_data->numRows - 1;

            if ( col >= d_data->numColumns )
                col = d_data->numColumns - 1;

            value = d_data->value( row, col );
        }
    }

    return value;
}

//.........这里部分代码省略.........

        for ( int x = 0; x < raster.width() - 1; x++ )
        {
            const QPointF pos( rect.x() + x * dx, rect.y() + y * dy );

            if ( x == 0 )
            {
                xy[TopRight].setX( pos.x() );
                xy[TopRight].setY( pos.y() );
                xy[TopRight].setZ(
                    value( xy[TopRight].x(), xy[TopRight].y() )
                );

                xy[BottomRight].setX( pos.x() );
                xy[BottomRight].setY( pos.y() + dy );
                xy[BottomRight].setZ(
                    value( xy[BottomRight].x(), xy[BottomRight].y() )
                );
            }

            xy[TopLeft] = xy[TopRight];
            xy[BottomLeft] = xy[BottomRight];

            xy[TopRight].setX( pos.x() + dx );
            xy[TopRight].setY( pos.y() );
            xy[BottomRight].setX( pos.x() + dx );
            xy[BottomRight].setY( pos.y() + dy );

            xy[TopRight].setZ(
                value( xy[TopRight].x(), xy[TopRight].y() )
            );
            xy[BottomRight].setZ(
                value( xy[BottomRight].x(), xy[BottomRight].y() )
            );

            double zMin = xy[TopLeft].z();
            double zMax = zMin;
            double zSum = zMin;

            for ( int i = TopRight; i <= BottomLeft; i++ )
            {
                const double z = xy[i].z();

                zSum += z;
                if ( z < zMin )
                    zMin = z;
                if ( z > zMax )
                    zMax = z;
            }

            if ( ignoreOutOfRange )
            {
                if ( !range.contains( zMin ) || !range.contains( zMax ) )
                    continue;
            }

            if ( zMax < levels[0] ||
                zMin > levels[levels.size() - 1] )
            {
                continue;
            }

            xy[Center].setX( pos.x() + 0.5 * dx );
            xy[Center].setY( pos.y() + 0.5 * dy );
            xy[Center].setZ( 0.25 * zSum );

            const int numLevels = levels.size();
            for ( int l = 0; l < numLevels; l++ )
            {
                const double level = levels[l];
                if ( level < zMin || level > zMax )
                    continue;
                QPolygonF &lines = contourLines[level];
                const ContourPlane plane( level );

                QPointF line[2];
                QwtPoint3D vertex[3];

                for ( int m = TopLeft; m < NumPositions; m++ )
                {
                    vertex[0] = xy[m];
                    vertex[1] = xy[0];
                    vertex[2] = xy[m != BottomLeft ? m + 1 : TopLeft];

                    const bool intersects =
                        plane.intersect( vertex, line, ignoreOnPlane );
                    if ( intersects )
                    {
                        lines += line[0];
                        lines += line[1];
                    }
                }
            }
        }
    }

    that->discardRaster();

    return contourLines;
}