This function has been introduced in the 2.0 trunk of the pChart library. It allows you to draw an arrow with some possible customisation like the size, angle and color. All the drawing parameters are given trough a $Format array. To learn more about this please read the Format array guide.

This function is also used internally while drawing the chart axis and the floating labels.

drawArrow($X1,$Y1,$X2,$Y2,$Format="");

Where :




It is possible to customize the arrow rendering by playing with this array. Providing a detailled configuration is not mandatory, by default the arrow will be drawn black with a size of 10 and a ratio of 1/2, filled with black.

 /* Enable shadow support */
 $myPicture->setShadow(TRUE,array("X"=>2,"Y"=>2,"R"=>0,"G"=>0,"B"=>0,"Alpha"=>20));

 /* We‘ll draw 25 arrow with different angles and transparency */
 for($i=1;$i<=100;$i=$i+4)
  {
   /* Settings of the arrow, we‘ll play with shades of grey */
   $arrowSettings = array("FillR"=>$i*2.5,"FillG"=>$i*2.5,"FillB"=>$i*2.5,"Ticks"=>$i % 5);

   /* Draw the arrow */
   $myPicture->drawArrow($i+5,215,$i*7+5,30,$arrowSettings);
  }

This will draw 25 arrows filled with progrssive grey shades and different Ticks length. This sample show that the head angle is internally computed. As the shadow support is enabled on line 2, the arrow will be surrounded by a small (+2,+2) shadow.