ChartDirector 6.0 (C++ Edition)

Square Angular Meters


      

This example demonstrates angular meters of which the pointers are pivoted at the corners of squares.

The meters in this example are achieved by using various start angles and end angles with 90 degrees angular span between them.

Source Code Listing

[The following code is available in "cppdemo/squareameter". A MFC version of the code is available in "mfcdemo/mfcdemo" (Windows edition only). A QT version of the code is available in "qtdemo/qtdemo".]
#include "chartdir.h"

void createChart(int chartIndex, const char *filename)
{
    // The value to display on the meter
    double value = 4.75;

    // Create an AugularMeter object of size 110 x 110 pixels, using silver background color with a
    // black 2 pixel 3D depressed border.
    AngularMeter *m = new AngularMeter(110, 110, Chart::silverColor(), 0x000000, -2);

    // Set meter appearance according to a parameter
    if (chartIndex == 0) {
        // Set the meter center at bottom left corner (15, 95), with radius 85 pixels. Meter spans
        // from 90 - 0 degrees.
        m->setMeter(15, 95, 85, 90, 0);
        // Add a label to the meter centered at (35, 75)
        m->addText(35, 75, "VDC", "arialbd.ttf", 12, Chart::TextColor, Chart::Center);
        // Add a text box to show the value at top right corner (103, 7)
        m->addText(103, 7, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff, Chart::TopRight
            )->setBackground(0, 0, -1);
    } else if (chartIndex == 1) {
        // Set the meter center at top left corner (15, 15), with radius 85 pixels. Meter spans from
        // 90 - 180 degrees.
        m->setMeter(15, 15, 85, 90, 180);
        // Add a label to the meter centered at (35, 35)
        m->addText(35, 35, "AMP", "arialbd.ttf", 12, Chart::TextColor, Chart::Center);
        // Add a text box to show the value at bottom right corner (103, 103)
        m->addText(103, 103, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff,
            Chart::BottomRight)->setBackground(0, 0, -1);
    } else if (chartIndex == 2) {
        // Set the meter center at top right corner (15, 95), with radius 85 pixels. Meter spans
        // from 270 - 180 degrees.
        m->setMeter(95, 15, 85, 270, 180);
        // Add a label to the meter centered at (75, 35)
        m->addText(75, 35, "KW", "arialbd.ttf", 12, Chart::TextColor, Chart::Center);
        // Add a text box to show the value at bottom left corner (7, 103)
        m->addText(7, 103, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff, Chart::BottomLeft
            )->setBackground(0, 0, -1);
    } else {
        // Set the meter center at bottom right corner (95, 95), with radius 85 pixels. Meter spans
        // from 270 - 360 degrees.
        m->setMeter(95, 95, 85, 270, 360);
        // Add a label to the meter centered at (75, 75)
        m->addText(75, 75, "RPM", "arialbd.ttf", 12, Chart::TextColor, Chart::Center);
        // Add a text box to show the value at top left corner (7, 7)
        m->addText(7, 7, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff, Chart::TopLeft
            )->setBackground(0, 0, -1);
    }

    // Meter scale is 0 - 10, with a major tick every 2 units, and minor tick every 1 unit
    m->setScale(0, 10, 2, 1);

    // Set 0 - 6 as green (99ff99) zone, 6 - 8 as yellow (ffff00) zone, and 8 - 10 as red (ff3333)
    // zone
    m->addZone(0, 6, 0x99ff99, 0x808080);
    m->addZone(6, 8, 0xffff00, 0x808080);
    m->addZone(8, 10, 0xff3333, 0x808080);

    // Add a semi-transparent black (80000000) pointer at the specified value
    m->addPointer(value, 0x80000000);

    // Output the chart
    m->makeChart(filename);

    //free up resources
    delete m;
}

int main(int argc, char *argv[])
{
    createChart(0, "squareameter0.png");
    createChart(1, "squareameter1.png");
    createChart(2, "squareameter2.png");
    createChart(3, "squareameter3.png");
    return 0;
}