Canvas gradients should not be optional

The spec says:

   "Support for actually painting gradients is optional. Instead of 
painting the gradients, user agents may instead just paint the first 
stop's color."

Firefox, Opera and Safari support gradients. Rhino Canvas does too. The 
recent (unreleased) Konqueror with <canvas> also does gradients. 
ExplorerCanvas attempts to support gradients, despite getting them 
utterly wrong - presumably it was decided that buggy gradient support 
was better than conformingly following the spec's option of no 
gradients. I can't remember any other implementations now.

Optional features are harder to test, and a worse implementation (which 
lacks the feature entirely) could claim better conformance than a better 
implementation (which has the feature, and maybe fails in a few obscure 
edge cases). Since every implementer has decided to implement gradients, 
it seems there is no compelling reason to not implement it. So, the 
"Support for actually painting gradients is optional" paragraph should 
be removed.

-- 
Philip Taylor
pjt47@cam.ac.uk

Received on Friday, 14 December 2007 12:22:40 UTC