Draw API

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The Draw API allows to create graphics through various drawing instruction. These instructions are grouped together and set as value of the draw attribute for any image object. E.g.

fill(color:150,150,150);rectangle(10,10,100,100,red,green);line(10,10,110,110,black);

Functions

Arc

arc(x, y, w, h, start, extent, type, border_color, fill_color)

Draws an arc. Parameters:

  • x: the x coordinate of the upper-left corner of the arc's framing rectangle
  • y: the y coordinate of the upper-left corner of the arc's framing rectangle
  • w: the overall width of the full ellipse of which this arc is a partial section
  • h: the overall height of the full ellipse of which this arc is a partial section
  • start: the starting angle of the arc in degrees
  • extent: the angular extent of the arc in degrees
  • type: the closure type for the arc: "open", "chord" or "pie"
  • border_color: fill color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red), or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.
  • fill_color: fill color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red), or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

Fill

fill(color)

Fills the whole area with given color Parameters:

  • color: color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red) or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow. Set color to "transparent" to create a transparent background, before drawing other objects.

Image

image(file, x, y)

Parameters:

  • file: the full pathname, relative to the HSYCO home directory
  • x: the x coordinate of the location where the String should be rendered - y: the y coordinate of the location where the String should be rendered

Line

line(x1, y1, x2, y2, ...., color)

Draws a sequence of connected lines - x1: X axis coordinate of first point Parameters:

  • y1: Y axis coordinate of first point
  • x2: X axis coordinate of second point
  • y2: Y axis coordinate of second point
  • xN: X axis coordinate of N-th point
  • yN: Y axis coordinate of N-th point
  • color: color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red), or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

Spline

spline(x1, y1, x2, y2, ...., color)

draws a natural cubic spline interpolation of a sequence of points - x1: X axis coordinate of first point Parameters:

  • y1: Y axis coordinate of first point
  • x2: X axis coordinate of second point
  • y2: Y axis coordinate of second point
  • xN: X axis coordinate of N-th point
  • yN: Y axis coordinate of N-th point
  • color: color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red), or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

Rectangle

rectangle(x, y, w, h, border_color, fill_color)

Parameters:

  • x: the x coordinate of the upper-left corner of the rectangle
  • y: the y coordinate of the upper-left corner of the rectangle
  • w: the width of the rectangle
  • h: the height of the rectangle
  • border_color: fill color can be set using an RGB comma separated numeric notation, with

primary color numbers from 0 to 255 (for example, “color:255,0,0” is red), or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

  • fill_color: fill color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red),

or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

String

string(text, x, y, font, style, size, color)

Parameters:

  • text: quoted text
  • x: the x coordinate of the location where the String should be rendered - y: the y coordinate of the location where the String should be rendered - font: font name, like “arial”, “helvetica”, “courier” etc.
  • style: “bold”, “italic”, or “bolditalic”
  • color: color can be set using an RGB comma separated numeric notation, with primary color numbers from 0 to 255 (for example, “color:255,0,0” is red),

or using color names. The valid names are: black, blue, cyan, darkgray, gray, lightgray, green, magenta, orange, pink, red, white, yellow.

Stroke

stroke(w)

Set the stroke width for all subsequent drawing commands. Parameters:

  • w: the width of the stroke

Examples

Draw a pie chart