2dos

see also TODOs in code

community
	upload results to server/community results page
		adapt API to allow import to UI
		define & document API
			improve compiler scheme image
		clientside code-based import & export
			what is "common" for code and ui
			version check
		serverside exchange method
		clientside browse and import
		clientside share
	show examples

small
	if eval() does thrown an error, colour the input field red to show that to the user
	show results of expressions beneath input field "=..." (on hover)
	make invoke-funcCall-drag better by adding a symbol to the cursor (as it is dragged)
	add switch for "add before or after" selected element
	indicateIfInsideAnySelectedCommandsScope on hover
	function name (& branch cond) input field has no drag event, but selections via mouse is disabled

big
	drag constant inside expression
	iconic code view
		rotate/move/loop with 0 is not visible
	edit Move style (colour, breadth)
	Collision-Free positioning
		check same state of commands, then shift y ?
	add svg-native circle/arc
	constraint solving
		snapping/line end handles
	bigger click radius, especially for Move
	variables can reference variables (on global scope)
	handling endless recursion by checking line-length or out of bounds
	How can the program flow be visualised (stepping through)?
	    3D: z-axis (depth) is passing time (rotate graphic to show time)
        timeslider: see the turtle move
	Map a parameter to space (show multiple "shadow instances" of it)
	selection z-order-handling (ALT selects below)
		this is actually hard, because event propagation will not work
		I will need to manually compute which elements a click hit
		http://mozilla.6506.n7.nabble.com/Event-Bubbling-through-Layers-td247852.html
	allow functions as arguments
	ctrl+d = duplicate selected command -> create proxy, instead of copy (ctrl+c) (can be emulated by funcCall)
        refactor "set scope" first
        think about how export should handle proxies
	undo
	store session in local browser cache
	allow much more dragging between elements
	Logo output
	automatic tests
	asynchronous (endless) recursion progression
		make recursion depth depend on run execution time
	store which expression requires which variables, so I only eval those
	drag in input field with expressions
	similar to "a" -> create parameters, new command to encapsulate selection into new function
	selected function block is more distinctly highlighted
	show individual parts in context (do not switch between pictures) - zooming in on detail
	scope highlighting: grey out rest, not the other way around


new commands
	mirror
	close path
		edit fill
	goto, go home, go to point in past
		go back X states in time
		idea: a pen stack: function calls may use the pen stack to "go home" after each call
	Beziers
	resize, rotate, shear