ChartDirector Ver 4.1 (C++ Edition)

Horizontal Linear Meter




This example demonstrates a simple horizontal linear meter.

A basic linear meter can be created using the following steps:

In addition to the basic linear meter, this example demonstrates the following features:

Source Code Listing

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

int main(int argc, char *argv[])
{
    // The value to display on the meter
    double value = 75.35;

    // Create an LinearMeter object of size 250 x 75 pixels, using silver background
    // with a 2 pixel black 3D depressed border.
    LinearMeter *m = new LinearMeter(250, 75, Chart::silverColor(), 0, -2);

    // Set the scale region top-left corner at (15, 25), with size of 200 x 50
    // pixels. The scale labels are located on the top (implies horizontal meter)
    m->setMeter(15, 25, 220, 20, Chart::Top);

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

    // Set 0 - 50 as green (99ff99) zone, 50 - 80 as yellow (ffff66) zone, and 80 -
    // 100 as red (ffcccc) zone
    m->addZone(0, 50, 0x99ff99);
    m->addZone(50, 80, 0xffff66);
    m->addZone(80, 100, 0xffcccc);

    // Add a blue (0000cc) pointer at the specified value
    m->addPointer(value, 0x0000cc);

    // Add a label at bottom-left (10, 68) using Arial Bold/8 pts/red (c00000)
    m->addText(10, 68, "Temperature C", "arialbd.ttf", 8, 0xc00000, Chart::BottomLeft
        );

    // Add a text box to show the value formatted to 2 decimal places at bottom
    // right. Use white text on black background with a 1 pixel depressed 3D border.
    m->addText(238, 70, m->formatValue(value, "2"), "arial.ttf", 8, 0xffffff,
        Chart::BottomRight)->setBackground(0, 0, -1);

    // output the chart
    m->makeChart("hlinearmeter.png");

    //free up resources
    delete m;
    return 0;
}