Simple Zooming and Scrolling (MFC)

[MFC version] mfcdemo/SimpleZoomScrollDlg.cpp
// SimpleZoomScrollDlg.cpp : implementation file
//

#include "stdafx.h"
#include "resource.h"
#include "SimpleZoomScrollDlg.h"
#include "chartdir.h"
#include <math.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#endif

//
// Constructor
//
CSimpleZoomScrollDlg::CSimpleZoomScrollDlg(CWnd* pParent /*=NULL*/)
    : CDialog(IDD_SIMPLEZOOMSCROLL, pParent)
{
    m_extBgColor = 0xffffff;
    m_ranSeries = 0;
}

//
// Destructor
//
CSimpleZoomScrollDlg::~CSimpleZoomScrollDlg()
{
    delete m_ranSeries;
    delete m_ChartViewer.getChart();
}

void CSimpleZoomScrollDlg::DoDataExchange(CDataExchange* pDX)
{
    CDialog::DoDataExchange(pDX);
    DDX_Control(pDX, IDC_PointerPB, m_PointerPB);
    DDX_Control(pDX, IDC_ChartViewer, m_ChartViewer);
}

BEGIN_MESSAGE_MAP(CSimpleZoomScrollDlg, CDialog)
    ON_BN_CLICKED(IDC_PointerPB, OnPointerPB)
    ON_BN_CLICKED(IDC_ZoomInPB, OnZoomInPB)
    ON_BN_CLICKED(IDC_ZoomOutPB, OnZoomOutPB)
    ON_CONTROL(CVN_ViewPortChanged, IDC_ChartViewer, OnViewPortChanged)
END_MESSAGE_MAP()


//
// Initialization
//
BOOL CSimpleZoomScrollDlg::OnInitDialog()
{
    CDialog::OnInitDialog();

    // Load icons to mouse usage buttons
    loadButtonIcon(IDC_PointerPB, IDI_PointerPB, 100, 20);  
    loadButtonIcon(IDC_ZoomInPB, IDI_ZoomInPB, 100, 20);    
    loadButtonIcon(IDC_ZoomOutPB, IDI_ZoomOutPB, 100, 20);

    //
    // Initialize member variables
    //
    m_extBgColor = getDefaultBgColor();     // Default background color

    // Load the data
    loadData();

    // Initialize the CChartViewer
    initChartViewer(&m_ChartViewer);

    // Trigger the ViewPortChanged event to draw the chart
    m_ChartViewer.updateViewPort(true, true);
    return TRUE;
}

//
// User clicks on the Pointer pushbutton
//
void CSimpleZoomScrollDlg::OnPointerPB() 
{
    m_ChartViewer.setMouseUsage(Chart::MouseUsageScroll);   
}

//
// User clicks on the Zoom In pushbutton
//
void CSimpleZoomScrollDlg::OnZoomInPB() 
{
    m_ChartViewer.setMouseUsage(Chart::MouseUsageZoomIn);   
}

//
// User clicks on the Zoom Out pushbutton
//
void CSimpleZoomScrollDlg::OnZoomOutPB() 
{
    m_ChartViewer.setMouseUsage(Chart::MouseUsageZoomOut);  
}

//
// The ViewPortChanged event handler. This event occurs if the user scrolls or zooms in or 
// out the chart by dragging or clicking on the chart. It can also be triggered by calling
// CChartViewer.updateViewPort.
//
void CSimpleZoomScrollDlg::OnViewPortChanged()
{
    if (m_ChartViewer.needUpdateChart())
        drawChart(&m_ChartViewer);
    if (m_ChartViewer.needUpdateImageMap())
        updateImageMap(&m_ChartViewer);
}

//
// Load the data
//
void CSimpleZoomScrollDlg::loadData()
{
    // In this example, we just use random numbers as data.
    m_ranSeries = new RanSeries(127);
    m_timeStamps = m_ranSeries->getDateSeries(1827, Chart::chartTime(2007, 1, 1), 86400);
    m_dataSeriesA = m_ranSeries->getSeries(1827, 150, -10, 10);
    m_dataSeriesB = m_ranSeries->getSeries(1827, 200, -10, 10);
    m_dataSeriesC = m_ranSeries->getSeries(1827, 250, -8, 8);
}

//
// Initialize the CChartViewer 
//
void CSimpleZoomScrollDlg::initChartViewer(CChartViewer *viewer)
{
    // Set the full x range to be the duration of the data
    viewer->setFullRange("x", m_timeStamps[0], m_timeStamps[m_timeStamps.len - 1]);

    // Initialize the view port to show the latest 20% of the time range
    viewer->setViewPortWidth(0.2);
    viewer->setViewPortLeft(1 - viewer->getViewPortWidth());

    // Set the maximum zoom to 10 points
    viewer->setZoomInWidthLimit(10.0 / m_timeStamps.len);

    // Enable mouse wheel zooming by setting the zoom ratio to 1.1 per wheel event
    viewer->setMouseWheelZoomRatio(1.1);

    // Initially set the mouse to drag to scroll mode.
    m_PointerPB.SetCheck(1);
    viewer->setMouseUsage(Chart::MouseUsageScroll);
}

//
// Draw the chart and display it in the given viewer
//
void CSimpleZoomScrollDlg::drawChart(CChartViewer *viewer)
{
    // Get the start date and end date that are visible on the chart.
    double viewPortStartDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft());
    double viewPortEndDate = viewer->getValueAtViewPort("x", viewer->getViewPortLeft() +
        viewer->getViewPortWidth());

    // Get the array indexes that corresponds to the visible start and end dates
    int startIndex = (int)floor(Chart::bSearch(m_timeStamps, viewPortStartDate));
    int endIndex = (int)ceil(Chart::bSearch(m_timeStamps, viewPortEndDate));
    int noOfPoints = endIndex - startIndex + 1;

    // Extract the part of the data array that are visible.
    DoubleArray viewPortTimeStamps = DoubleArray(m_timeStamps.data + startIndex, noOfPoints);
    DoubleArray viewPortDataSeriesA = DoubleArray(m_dataSeriesA.data + startIndex, noOfPoints);
    DoubleArray viewPortDataSeriesB = DoubleArray(m_dataSeriesB.data + startIndex, noOfPoints);
    DoubleArray viewPortDataSeriesC = DoubleArray(m_dataSeriesC.data + startIndex, noOfPoints);

    //
    // At this stage, we have extracted the visible data. We can use those data to plot the chart.
    //

    ///////////////////////////////////////////////////////////////////////////////////////
    // Configure overall chart appearance. 
    ///////////////////////////////////////////////////////////////////////////////////////

    // Create an XYChart object 600 x 300 pixels in size, with pale blue (0xf0f0ff) background,
    // black (000000) rounded border, 1 pixel raised effect.
    XYChart *c = new XYChart(600, 300, 0xf0f0ff, 0, 1);
    c->setRoundedFrame(m_extBgColor);

    // Set the plotarea at (52, 60) and of size 520 x 205 pixels. Use white (ffffff) background.
    // Enable both horizontal and vertical grids by setting their colors to grey (cccccc). Set
    // clipping mode to clip the data lines to the plot area.
    c->setPlotArea(52, 60, 520, 205, 0xffffff, -1, -1, 0xcccccc, 0xcccccc);
    
    // As the data can lie outside the plotarea in a zoomed chart, we need to enable clipping.
    c->setClipping();

    // Add a top title to the chart using 15 pts Times New Roman Bold Italic font, with a light blue
    // (ccccff) background, black (000000) border, and a glass like raised effect.
    c->addTitle("Simple Zooming and Scrolling", "Times New Roman Bold Italic", 15
        )->setBackground(0xccccff, 0x0, Chart::glassEffect());

    // Add a legend box at the top of the plot area with 9pts Arial Bold font with flow layout.
    c->addLegend(50, 33, false, "Arial Bold", 9)->setBackground(Chart::Transparent, Chart::Transparent);

    // Set axes width to 2 pixels
    c->yAxis()->setWidth(2);
    c->xAxis()->setWidth(2);

    // Add a title to the y-axis
    c->yAxis()->setTitle("Price (USD)", "Arial Bold", 9);

    ///////////////////////////////////////////////////////////////////////////////////////
    // Add data to chart
    ///////////////////////////////////////////////////////////////////////////////////////

    // 
    // In this example, we represent the data by lines. You may modify the code below to use other
    // representations (areas, scatter plot, etc).
    //

    // Add a line layer for the lines, using a line width of 2 pixels
    LineLayer *layer = c->addLineLayer();
    layer->setLineWidth(2);

    // In this demo, we do not have too many data points. In real code, the chart may contain a lot
    // of data points when fully zoomed out - much more than the number of horizontal pixels in this
    // plot area. So it is a good idea to use fast line mode.
    layer->setFastLineMode();

    // Now we add the 3 data series to a line layer, using the color red (ff0000), green
    // (00cc00) and blue (0000ff)
    layer->setXData(viewPortTimeStamps);
    layer->addDataSet(viewPortDataSeriesA, 0xff0000, "Product Alpha");
    layer->addDataSet(viewPortDataSeriesB, 0x00cc00, "Product Beta");
    layer->addDataSet(viewPortDataSeriesC, 0x0000ff, "Product Gamma");

    ///////////////////////////////////////////////////////////////////////////////////////
    // Configure axis scale and labelling
    ///////////////////////////////////////////////////////////////////////////////////////
    
    // Set the x-axis as a date/time axis with the scale according to the view port x range.
    viewer->syncDateAxisWithViewPort("x", c->xAxis());

    // In this demo, we rely on ChartDirector to auto-label the axis. We ask ChartDirector to ensure
    // the x-axis labels are at least 75 pixels apart to avoid too many labels.
    c->xAxis()->setTickDensity(75);

    ///////////////////////////////////////////////////////////////////////////////////////
    // Output the chart
    ///////////////////////////////////////////////////////////////////////////////////////

    delete viewer->getChart();
    viewer->setChart(c);
}

//
// Update the image map
//
void CSimpleZoomScrollDlg::updateImageMap(CChartViewer *viewer)
{
    // Include tool tip for the chart
    if (0 == viewer->getImageMapHandler())
    {
        viewer->setImageMap(viewer->getChart()->getHTMLImageMap("", "",
            "title='[{dataSetName}] {x|mmm dd, yyyy}: USD {value|2}'"));
    }
}

/////////////////////////////////////////////////////////////////////////////
// General utilities

//
// Get the default background color
//
int CSimpleZoomScrollDlg::getDefaultBgColor()
{
    LOGBRUSH LogBrush; 
    HBRUSH hBrush = (HBRUSH)SendMessage(WM_CTLCOLORDLG, (WPARAM)CClientDC(this).m_hDC, 
        (LPARAM)m_hWnd); 
    ::GetObject(hBrush, sizeof(LOGBRUSH), &LogBrush); 
    int ret = LogBrush.lbColor;
    return ((ret & 0xff) << 16) | (ret & 0xff00) | ((ret & 0xff0000) >> 16);
}

//
// Load an icon resource into a button
//
void CSimpleZoomScrollDlg::loadButtonIcon(int buttonId, int iconId, int width, int height)
{
    // Resize the icon to match the screen DPI for high DPI support
    HDC screen = ::GetDC(0);
    double scaleFactor = GetDeviceCaps(screen, LOGPIXELSX) / 96.0;
    ::ReleaseDC(0, screen);
    width = (int)(width * scaleFactor + 0.5);
    height = (int)(height * scaleFactor + 0.5);

    GetDlgItem(buttonId)->SendMessage(BM_SETIMAGE, IMAGE_ICON, (LPARAM)::LoadImage(
        AfxGetResourceHandle(), MAKEINTRESOURCE(iconId), IMAGE_ICON, width, height,
        LR_DEFAULTCOLOR));
}