ChartDirector 6.0 (C++ Edition)

Color Horizontal Bar Meters


          

This example demonstrates horizontal bar meters in various colors, with different color scales, and with title and value readout.

BaseMeter.addColorScale is used to create the color scales in the meters. The color scales are created by with different colors, different end point positions and different widths at the end points.

The title and value readout are created using BaseChart.addText. The value readout is configured to have a black background and a depressed border using Box.setBackground, and with rounded corners using Box.setRoundedCorners.

Source Code Listing

[The following code is available in "cppdemo/colorhbarmeter". 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 = 75.35;

    // The background, border and bar colors of the meters
    int bgColor[] = {0xbbddff, 0xccffcc, 0xffddff, 0xffffaa, 0xffdddd, 0xeeeeee};
    int borderColor[] = {0x000088, 0x006600, 0x880088, 0xee6600, 0x880000, 0x666666};
    int barColor[] = {0x0088ff, 0x00cc00, 0x8833dd, 0xff8800, 0xee3333, 0x888888};

    // Create a LinearMeter object of size 260 x 80 pixels with a 3-pixel thick rounded frame
    LinearMeter *m = new LinearMeter(260, 80, bgColor[chartIndex], borderColor[chartIndex]);
    m->setRoundedFrame(Chart::Transparent);
    m->setThickFrame(3);

    // Set the scale region top-left corner at (18, 24), with size of 222 x 20 pixels. The scale
    // labels are located on the top (implies horizontal meter)
    m->setMeter(18, 24, 222, 20, Chart::Top);

    // Set meter scale from 0 - 100, with a tick every 10 units
    m->setScale(0, 100, 10);

    if (chartIndex % 4 == 0) {
        // Add a 5-pixel thick smooth color scale at y = 48 (below the meter scale)
        double smoothColorScale[] = {0, 0x0000ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100,
            0xff0000};
        m->addColorScale(DoubleArray(smoothColorScale, (int)(sizeof(smoothColorScale) / sizeof(
            smoothColorScale[0]))), 48, 5);
    } else if (chartIndex % 4 == 1) {
        // Add a 5-pixel thick step color scale at y = 48 (below the meter scale)
        double stepColorScale[] = {0, 0x00cc00, 50, 0xffdd00, 80, 0xff3333, 100};
        m->addColorScale(DoubleArray(stepColorScale, (int)(sizeof(stepColorScale) / sizeof(
            stepColorScale[0]))), 48, 5);
    } else if (chartIndex % 4 == 2) {
        // Add a 5-pixel thick high/low color scale at y = 48 (below the meter scale)
        double highLowColorScale[] = {0, 0x0000ff, 40, Chart::Transparent, 60, Chart::Transparent,
            100, 0xff0000};
        m->addColorScale(DoubleArray(highLowColorScale, (int)(sizeof(highLowColorScale) / sizeof(
            highLowColorScale[0]))), 48, 5);
    } else {
        // Add a 5-pixel thick high only color scale at y = 48 (below the meter scale)
        double highColorScale[] = {70, Chart::Transparent, 100, 0xff0000};
        m->addColorScale(DoubleArray(highColorScale, (int)(sizeof(highColorScale) / sizeof(
            highColorScale[0]))), 48, 0, 48, 8);
    }

    // Add a bar from 0 to value with glass effect and 4 pixel rounded corners
    m->addBar(0, value, barColor[chartIndex], Chart::glassEffect(Chart::NormalGlare, Chart::Top), 4)
        ;

    // Add a label right aligned to (243, 65) using 8pt Arial Bold font
    m->addText(243, 65, "Temperature C", "arialbd.ttf", 8, Chart::TextColor, Chart::Right);

    // Add a text box left aligned to (18, 65). Display the value using white (0xffffff) 8pt Arial
    // Bold font on a black (0x000000) background with depressed rounded border.
    TextBox *t = m->addText(18, 65, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff,
        Chart::Left);
    t->setBackground(0x000000, 0x000000, -1);
    t->setRoundedCorners(3);

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

    //free up resources
    delete m;
}

int main(int argc, char *argv[])
{
    createChart(0, "colorhbarmeter0.png");
    createChart(1, "colorhbarmeter1.png");
    createChart(2, "colorhbarmeter2.png");
    createChart(3, "colorhbarmeter3.png");
    createChart(4, "colorhbarmeter4.png");
    createChart(5, "colorhbarmeter5.png");
    return 0;
}