> Feedback on Glaciers Sim Design (version 2) 
> Chris Malley (Oct 31, 2007)

Responses to Chris' feedback
Archie Paulson (Oct 31, 2007)

> Map view should be the same image as the Main view -- an image of the
> entire valley, from the perspective shown in the Main view.  The Map
> view shows the entire image and the Main view shows one "zoomed in"
> section of it.   The Little Box in the Map view can only be dragged
> left-right. Having a birds-eye Map view just makes it harder to use
> and harder to implement.
>
> This interface relies heavily on the ability of the user to figure out
> how to use the Map view.  This type of interface control is very
> advanced; will users know what to do?

After discussion with Chris, it looks like the map view can be
replaced by a long zoomed-out view of the entire glacier valley.
I will work this into the mockup so we can talk about it.

> The font used in "View" and "Climate Controls" panels is small. I
> guarantee that I'll be asked to increase it at some point during
> development.  If this happens, we'll lose vertical space for the Map
> and Main views.  Do we want to see what this interface looks like with
> a more typical font size?

I'll increase the font size.  I think the toolbox can be made smaller,
and the map view at the top should be smaller once the change above is
made, so that should buy us some space.

> Is toolbox movable?  If so, it will not be movable outside the play
> area.  In order to drag stuff from the toolbox to the glaciers, the
> toolbox must be part of the play area. (I can provide more technical
> details if this isn't clear.)

No, the toolbox does not need to move.

> Which valley floor option is being shown? Is it linear, or is there a
> bump somewhere further down the valley?
> Removing the option to change the shape of the valley floor (slide 3,
> bullet 1) removes a very significant cost. This is good if you really
> don't need this option. But if you think you might want this option
> (as hinted at in Slide 24, bullet 3) then it should be included from
> the beginning.  There are lots of nice simplfications we can make if
> the floor is linear (no space for a control needed, no need to curve
> fit with valley floor, no need to orient ruler with slope, etc).  But
> these simplifications will be devastating if we later decide that we
> need to change the floor shape.

The valley shown is linear, and I think we can stick with the linear
shape, but I'll check with the glacier expert to make sure we don't
need other shapes. It would be nice to be able to change the value of
the linear slope, but that does not require much change at all (only
values on the coordinates and some effect in the equations of motion).

> "Reset All" is placed between "Restart" and "Pause".  "Reset All" is
> not a time control, and all interface elements related to time should
> be grouped together (maybe put a box around them).  Move "Reset All"
> button to left of "Help" button and I think you're OK.

Will do.

> Placing the control panel at the bottom adds development cost.  Ditto
> for the non-standard "Reset All" and "Set Glacier to Equilibrium"
> buttons.  We won't be able to use phetcommon facilities that handle
> standard simulation layout, and future changes/enhancements to the
> standard layout won't be applied to this simulation.  I don't see that
> we have any other choice here, but wanted everyone to be aware of the
> implications.

I think we need the horizontal layout to maximize the amount of
glacier that is visible.  The 'set glacier to eq' button is not really
translatable to other sims, so there is no help from phetcommon there.

> Slide #10 indicates that the controls for "snow fall and temperature"
> are shown on the previous slide.  But the previous slide now has "mass
> balance" selected.  (Slide #11 shows the controls, but you still might
> want to list them explicitly here.)

Typo corrected.

> Slide #10 (last bullet) still refers to "the button next to Set
> glacier to equilibrium state".  This is now a labeled button and is no
> longer in the Climate Control panel. If this button is relevant to the
> climate controls, then you should reconsider your decision to move the
> button elsewhere.  Was the motivation for this decision solely space
> constraints?

This button is not really a climate control, so I don't think it
should be in that box. It is more of a reset-type button.

> I don't understand the climate controls that control rate of change of
> parameters. (Slides 11, 12, 13)  And I'm not confident that users know
> how to interpret these controls.  Please elaborate, maybe with some
> examples.

I could use some better ideas here.  The intent is to be able to set
both (1) the climate at the present time and (2) how the climate will
evolve, if at all.  The defaults should be set to zero change, so that
the glacier responds directly to the user's manipulation of the
controls.  The user should also be able to, for example, go from the
climate at the Last Glacial Maximum (a period about 12000 years ago)
to the present-day conditions while watching the glacier's response.
The 'change' options could be hidden under and 'advanced options'
button, perhaps.  Or there could be a radio button that is set to
either 'constant climate' or 'change climate to...', where the
controls for climate change are greyed out if the first radio button
is selected. I have been struggling with how to offer this feature,
and could use any ideas (thanks to Sam M for what's there now).

> Slide 14 bullet 8 says that the "ruler can be used to measure down-
> slope distance".  How are we going to get the ruler aligned with the
> slope? Or is the slope the same for the entire valley, in which case
> we can set the ruler at a fixed slope? If you decide you want the
> "change floor shape" feature, how will this affect the ruler?

I anticipate the valley floor being a simple linear slope. The ruler,
then, will only be measuring the distance down that slope.

> Slide #20, regarding the toolbox... In addition to the Trash can, I
> think we should also allow users to remove tools by dragging them back
> to where they got them.

Good idea.

> Where did you get these images? If you didn't make them, which of them
> have licensing issues? (I need to know which images I can safely lift
> from the design document without violating copyrights.)
> - thermometer
> - snowfall gauge
> - ice thickness tool
> - trash can
> - borehole drill

Once the map view is changed (as per first point, above), there will
be no proprietary images.  I drew everything from scratch except for
the trashcan and the drill, which were taken from www.openclipart.org
(and everything there is strictly under 'Public Domain').

> How do I get rid of all instances of a particular tool? For example,
> I've placed 20 marker flags and I want to remove them all.

Hm, I don't know.  Any ideas from the group?

> Describe what happens when the user resizes the simulation's window.
> Typically, everything in the play area scales up or down, but I don't
> think you want the typical behavior. Relevant questions: If the window
> is resized, do you want the Toolbox to change size or  stay constant?
> If the window is resized, do you want the Map view to change size or
> stay constant?  If the entire Map view is visible at 1024x768, what do
> we see when  the window is resized to 1600x768?  Does the Main view
> change scale when the window is resized, or does  the scale remain
> constant and the size of the Little Box in the Main  view change?

After some discussion with Chris, the following solution seems
reasonable. First, there will be no accomodations for a window size
smaller than 1024x768; the view will just be clipped. For increased
horizontal window size, the map-view will not change -- it will just
stay in the middle of the screen with grey area on the left and right.
The main view will show more of the valley when the window gets wider
(this may lead to part of the glacier going off-screen below or above
the view area, but the user will easily be able the pan the main view
to see those parts if s/he so desires). Increased window height will
only show more empty underground earth or empty sky.