[Proj] hammer parameters?

[William Kyngesburye]

I need to replicate a Breisemeister projection.  So far I've figured out that it's a special case of the Hammer.

GRASS tell me that the Hammer needs a lat/long center, and also an "M" and "W" factor which default to 1 and 0.5 respectively.  What are these?  All I know is that the Breisemeister has an ellipse (shape) ratio of 1.75:1 (and the center is 45N 10E).  Info on the Hammer says the ratio is 2:1, which matches GRASS' default M/W of 1/0.5.

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William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

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