ChartDirector 6.0 (C++ Edition)

Angular Meter Pointers (2)




This example demonstrates adding multiple new style pointers of different styles to a meter.

For angular meters, classical pointers are added using BaseMeter.addPointer, while new style pointers are added using AngularMeter.addPointer2.

When compared to classical pointers, new style pointers are thinner. They are designed to be used with the new style meter cap (the circular object at the center), which is larger than the classical pointer cap, and is configurable using AngularMeter.setCap2. The base and tip of the new style pointer can move independently in the radial direction, which means the pointer can be detached from the center, and can even points from the outside inwards.

Source Code Listing

[The following code is available in "cppdemo/angularpointer2". 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"

int main(int argc, char *argv[])
{
    // Create an AngularMeter object of size 300 x 300 pixels with transparent background
    AngularMeter *m = new AngularMeter(300, 300, Chart::Transparent);

    // Set the default text and line colors to white (0xffffff)
    m->setColor(Chart::TextColor, 0xffffff);
    m->setColor(Chart::LineColor, 0xffffff);

    // Center at (150, 150), scale radius = 125 pixels, scale angle 0 to 360 degrees
    m->setMeter(150, 150, 125, 0, 360);

    // Add a black (0x000000) circle with radius 148 pixels as background
    m->addRing(0, 148, 0x000000);

    // Add a ring between radii 139 and 147 pixels using the silver color with a light grey
    // (0xcccccc) edge as border
    m->addRing(139, 147, Chart::silverColor(), 0xcccccc);

    // Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
    m->setScale(0, 100, 10, 5, 1);

    // Set the scale label style to 16pt Arial Italic. Set the major/minor/micro tick lengths to
    // 13/10/7 pixels pointing inwards, and their widths to 2/1/1 pixels.
    m->setLabelStyle("ariali.ttf", 16);
    m->setTickLength(-13, -10, -7);
    m->setLineWidth(0, 2, 1, 1);

    // Add a default red (0xff0000) pointer
    m->addPointer2(25, 0xff0000);

    // Add a semi-transparent green (0x3f00ff00) line style pointer
    m->addPointer2(9, 0x3f00ff00, -1, Chart::LinePointer2);

    // Add a semi-transparent blue (0x7f66aaff) triangular pointer floating between 60% and 85% of
    // the scale radius with the pointer width 5 times the default
    m->addPointer2(52, 0x7f66aaff, 0x66aaff, Chart::TriangularPointer2, 0.6, 0.85, 5);

    // Add a semi-transparent yellow (0x7fffff66) triangular pointer floating between 80% and 90% of
    // the scale radius with the pointer width 5 times the default
    m->addPointer2(65, 0x7fffff66, 0xffff66, Chart::TriangularPointer2, 0.8, 0.9, 5);

    // Add two red (0xff0000) triangular pointer at 72 and 94. The pointers float between 110% and
    // 100% of the scale radius with widths 3 times the default
    m->addPointer2(72, 0xff0000, -1, Chart::TriangularPointer2, 1.1, 1.0, 3);
    m->addPointer2(94, 0xff0000, -1, Chart::TriangularPointer2, 1.1, 1.0, 3);

    // Add a red (0xcc0000) zone spanning from 72 to 94, and between the radii 112 and 125
    m->addZone(72, 94, 125, 112, 0xcc0000);

    // Output the chart
    m->makeChart("angularpointer2.png");

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