topical media & game development
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

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professional-sql-09-lib-BarChart.php / php



  <?php
  class BarChart
  {
      private width;   // width of chart
      private height;  // height of chart
      private image;   // image reference
      private black;   // allocated color black
  
      // initialize new object
      public function __construct(width, height)
      {
          // create new image
          this->image = imagecreatetruecolor(width, height);
          this->width = width;
          this->height = height;
  
          // fill image background white
          white = imagecolorallocate(this->image, 0xFF, 0xFF, 0xFF);
          imagefill(this->image, 0,0, white);
  
          // draw axis
          this->black = imagecolorallocate(this->image, 0x00, 0x00, 0x00);
          imageline(this->image, 20, 0, 20, height - 20, this->black);
          imageline(this->image, 20, height - 20, width - 20, height - 20,
              this->black);
      }
  
      // dump image to browser or save
      public function flushImage(filename = '')
      {
          if (filename)
          {
              imagepng(this->image, filename);
          }
          else
          {
              header('Content-type: image/png');
              imagepng(this->image);
          }
      }
  
      // graph the data using the associated colors and labels
      public function graphData(data, colors, labels)
      {
          // start point
          x = 20;
          y = this->height - 20;
  
          // calculate bar width
          bar_width = (this->width - x - 20) / count(data);
  
          ymax = max(data);
  
          foreach (data as i => dat)
          {
              // calculate height of bar
              bar_height = (dat / ymax) * (this->height - 30);
              color = imagecolorallocate(this->image, colors[i]['r'],
                  colors[i]['g'], colors[i]['b']);
  
              // draw bar twice - once for filled area and again for outline
              imagefilledrectangle(this->image, x, y, x + bar_width,
                  y - bar_height, color);
              imagerectangle(this->image, x, y, x + bar_width,
                  y - bar_height, this->black);
  
              imagestring(this->image, 2, x, y, labels[i], this->black);
  
              // increment starting point
              x += bar_width;
          }
      }
  }
  ?>
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

(C) Æliens 20/2/2008

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