ChartDirector 7.1 (C++ Edition)

Color Horizontal Linear Meters


          

This example demonstrates horizontal linear 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 is the command line version of the code in "cppdemo/colorhlinearmeter". The MFC version of the code is in "mfcdemo/mfcdemo". The Qt Widgets version of the code is in "qtdemo/qtdemo". The QML/Qt Quick version of the code is in "qmldemo/qmldemo".
#include "chartdir.h" void createChart(int chartIndex, const char *filename) { // The value to display on the meter double value = 74.25; // The background and border colors of the meters int bgColor[] = {0xbbddff, 0xccffcc, 0xffccff, 0xffffaa, 0xffdddd, 0xeeeeee}; const int bgColor_size = (int)(sizeof(bgColor)/sizeof(*bgColor)); int borderColor[] = {0x000088, 0x006600, 0x6600aa, 0xee6600, 0x880000, 0x666666}; const int borderColor_size = (int)(sizeof(borderColor)/sizeof(*borderColor)); // Create a LinearMeter object of size 250 x 75 pixels with a 3-pixel thick rounded frame LinearMeter* m = new LinearMeter(250, 75, bgColor[chartIndex], borderColor[chartIndex]); m->setRoundedFrame(Chart::Transparent); m->setThickFrame(3); // Set the scale region top-left corner at (14, 23), with size of 218 x 20 pixels. The scale // labels are located on the top (implies horizontal meter) m->setMeter(14, 23, 218, 20, Chart::Top); // Set meter scale from 0 - 100, with a tick every 10 units m->setScale(0, 100, 10); // Demostrate different types of color scales and putting them at different positions double smoothColorScale[] = {0, 0x6666ff, 25, 0x00bbbb, 50, 0x00ff00, 75, 0xffff00, 100, 0xff0000}; const int smoothColorScale_size = (int)(sizeof(smoothColorScale)/sizeof(*smoothColorScale)); double stepColorScale[] = {0, 0x33ff33, 50, 0xffff33, 80, 0xff3333, 100}; const int stepColorScale_size = (int)(sizeof(stepColorScale)/sizeof(*stepColorScale)); double highLowColorScale[] = {0, 0x6666ff, 70, Chart::Transparent, 100, 0xff0000}; const int highLowColorScale_size = (int)(sizeof(highLowColorScale)/sizeof(*highLowColorScale)); if (chartIndex == 0) { // Add the smooth color scale at the default position m->addColorScale(DoubleArray(smoothColorScale, smoothColorScale_size)); } else if (chartIndex == 1) { // Add the step color scale at the default position m->addColorScale(DoubleArray(stepColorScale, stepColorScale_size)); } else if (chartIndex == 2) { // Add the high low scale at the default position m->addColorScale(DoubleArray(highLowColorScale, highLowColorScale_size)); } else if (chartIndex == 3) { // Add the smooth color scale starting at y = 23 (top of scale) with zero width and ending // at y = 23 with 20 pixels width m->addColorScale(DoubleArray(smoothColorScale, smoothColorScale_size), 23, 0, 23, 20); } else if (chartIndex == 4) { // Add the smooth color scale starting at y = 33 (center of scale) with zero width and // ending at y = 23 with 20 pixels width m->addColorScale(DoubleArray(smoothColorScale, smoothColorScale_size), 33, 0, 23, 20); } else { // Add the smooth color scale starting at y = 43 (bottom of scale) with zero width and // ending at y = 23 with 20 pixels width m->addColorScale(DoubleArray(smoothColorScale, smoothColorScale_size), 43, 0, 23, 20); } // Add a blue (0x0000cc) pointer at the specified value m->addPointer(value, 0x0000cc); // Add a label left aligned to (10, 61) using 8pt Arial Bold font m->addText(10, 61, "Temperature C", "Arial Bold", 8, Chart::TextColor, Chart::Left); // Add a text box right aligned to (235, 61). Display the value using white (0xffffff) 8pt Arial // Bold font on a black (0x000000) background with depressed rounded border. TextBox* t = m->addText(235, 61, m->formatValue(value, "2"), "Arial Bold", 8, 0xffffff, Chart::Right); 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, "colorhlinearmeter0.png"); createChart(1, "colorhlinearmeter1.png"); createChart(2, "colorhlinearmeter2.png"); createChart(3, "colorhlinearmeter3.png"); createChart(4, "colorhlinearmeter4.png"); createChart(5, "colorhlinearmeter5.png"); return 0; }