[Doxygen-develop] [PATCH] Formula transparency patch.

[E. R. <er...@ca...>]

I've attached a patch to render formulas slightly differently. The current 
method of rendering is to render the formula to a white background, then output 
the exact colour as opaque, except for pure white which is set to fully 
transparent.

The new method (attached) renders all non white pixels as pure black, but sets 
various levels of transparency to achieve a smooth effect. This ensures that 
the equations render correctly if the web browser background is not set to 
white.

I haven't quite figured out how to set it up so that it can be switched on with 
a configuration option.

To illustrate the method with a rather exxtreme example, I've composited a 
sample formula against a dark blue background, and attached the images.

Regards

-Ed


-- 
(You can't go wrong with psycho-rats.)(http://mi.eng.cam.ac.uk/~er258)

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