Drawing on the Canvas - HTML5 Canvas - page 102

Of course, using a string for the color name is not the only available method of specifying a
solid color fill. The following list includes a few other methods:

Setting the fill color with the rgb() rgb() method

The rgb() method lets us use the 24-bit RGB value when specifying our fill colors:

context . fillStyle = "rgb(255,0,0)" ;

This will result in the same red color as the string value above.

Setting the fill color with a hex number string

We can also set the fillStyle color with a hex number in a string:

context . fillStyle = "#ff0000" ;

Setting the fill color with the rgba() rgba() method

The rgba() method allows us to specify a 32-bit color value with the final 8 bits repres-
enting the alpha value of the fill color:

context . fillStyle = "rgba(255,0,0,1)" ;

The alpha value can be from 1 (opaque) to 0 (transparent).