gNumerator

Under and Over (<munder>, <mover>, <munderover>) elements are now implemented. To get these working actually required more work on the DOM side of things as opposed to the rendering side. Rendering (with the exception of stretching the horizontal operators) is actually fairly straightforward. Essentially, each under or over element is simply a vertical array, with the under or over element optionally shrunk down to a script size. The trick however is actually figuring out when and if to shrink the under and over elements.

Here is a good example of rendering a mathml document with some <munder> elements.

source mathml for this screenshot

Here is a screenshot of GtkMathView rendering the same mathml. Notice the almost identical layout, even thought the gNumerator rendering control is written in c#, and running on windows, and GtkMathView is written in c++ and running on linux.

source mathml for this screenshot

Here is another shot, with the previous mathml document slightly modified with a very long base element in the <munder> element. This causes the right arrow stretchy operator in the underscript element to stretch to fill the the horizontal extent of the base element. If the underscript was wider than the base, and the base had operators that could stretch horizontally, the base would have stretched to fill the needed extent.

source mathml for this screenshot