When drawing vector graphics in the canvas you set the fillStyle using an rgba string like this...

context.fillStyle = "rgba(255, 223, 191, 1)";

Is it possible to feed in a javascript object instead (or just numbers). Seems silly that I would need to construct a string to feed to this value if I wanted the color dynamic.

context.fillStyle = "rgba(255, 223, 191, " + alpha + ")";

The specification clearly says "a CSS Color string" but it seems crazy. Am I missing something?


update: I switched to using globalAlpha for this specific example. But still seems crazy.


1 Answer 1


Nope, you're not missing anything. This has to be a string, containing a valid CSS color value.

To reassure you, you're not the first one wondering why so much hate.


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