OpenTTD
Modules
Here is a list of all modules:
oDirtyHandles the repaint of some part of the screen
oSnowline functions and data structures
oRows and columns in the viewportColumns are vertical sections of the viewport that are half a tile wide
oHierarchical widgetsHierarchical widgets, also known as nested widgets, are widgets stored in a tree
\Hierarchical widget partsTo make nested widgets easier to enter, nested widget parts have been created