NEzoom.sml

# NEzoom.sml

# View ToolScript that provides zoom in on left mouse click
# with variable zoom capability depending on current scale.
# At scale > 1,000,000 zooms to county polygon.
# At scale > 25,000 zooms in 4X at click-point.
# At scale < 25,000 zooms to maximum detail (1X) in orthoimage layer.

# Author: Randy Smith, MicroImages, Inc.
#			January 2006.

# Revised 9 June 2006:
#		After zooming to a county, if initally click outside that county,
#		tool zooms to the new county. However, this rule is inactivated once
#		left-click/zoom within the current county.

# Revised 13 June 2006:
#		Added messages to View status line to identify current left-click action,
#		with Spanish and Turkish translations.

# The following symbols are predefined
#    class GRE_VIEW View            {use to access the view the tool script is attached to}
#    class GRE_GROUP Group          {use to access the group being viewed if the script is run from a group view}
#    class GRE_LAYOUT Layout        {use to access the layout being viewed if the script is run from a layout view}
#    numeric ToolIsActive           Will be 0 if tool is inactive or 1 if tool is active
#
# The following values are also predefined and are valid when the various On...()
# functions are called which deal with pointer and keyboard events.
#    numeric PointerX            Pointer X coordinate within view in pixels
#    numeric PointerY            Pointer Y coordinate within view in pixels
#    numeric ShiftPressed        1 if  key being pressed or 0 if not
#    numeric CtrlPressed         1 if  key being pressed or 0 if not
#    numeric LeftButtonPressed   1 if left pointer button pressed or 0 if not
#    numeric RightButtonPressed  1 if right pointer button pressed or 0 if not
#    numeric MiddleButtonPressed 1 if middle pointer button pressed or 0 if not
#

########################################
### Global variable declarations
########################################

# group/layer/object global variables
class GRE_LAYER_VECTOR cntyLayer;	# county vector layer
class GRE_LAYER_VECTOR cntyLayer;	# county vector layer
class VECTOR cntyVector;				# county vector object
class GRE_VECTOR_POLYS cntyPolys;	# handle for polygon elements in county vector object

class TRANSPARM layerTransparm;			## coordinate transformation parameters from screen to vector layer
class TRANSPARM viewTransparm;			## coordinate transformation parameters from screen to view (group map coordinates)

numeric lastCnty;				# polygon number of last county clicked in
numeric zoomedBelowCnty;	# flag to indicate if have zoomed in after zooming to county
numeric mapscale;				### current map scale of View

string language$;
string msg1$, msg2$, msg3$;	# zoom prompt messages for View message field

# The following script functions will be called (if used in the script) when
# the appropriate action or event occurs as described in the comments before each.
# To use a function, uncomment the lines containing the 'func' definition
# and ending brace '}' by removing the leftmost '#' on the line and add the
# function code between the two lines.


# Called the first time the tool is activated.
# If the tool implements a dialog it should be created (but not displayed) here.
proc OnInitialize ()
	{
	Group = Layout.FirstGroup;

	## iterate through groups to find Nebraska Data group
	while (Group.Name != "Nebraska Data")
		Group = Group.NextGroup;

	# get Counties layer from the group and polygons from the layer
	cntyLayer = Group.GetLayerByName("Counties");
	cntyPolys = cntyLayer.Poly;

	# get the vector object from the layer
	DispGetVectorFromLayer(cntyVector, cntyLayer);

	# set prompt message strings
	language$ = _context.Locale;

	if (language$ == "enu")
		{
		msg1$ = "Left-click in a Nebraska County to zoom to it.";
		msg2$ = "Left-click to zoom in to that point.";
		msg3$ = "Left-click to recenter the view on that point.";
		}
	else if (language$ == "esn")
		{
		msg1$ = "Clic izquierdo en un Condado de Nebraska para hacer zoom en él.";
		msg2$ = "Clic izquierdo para hacer zoom en ese punto.";
		msg3$ = "Clic izquierdo para recentrar la vista en ese punto.";
		}
	else if (language$ == "trk")
		{
		msg1$ = "Tıklayarak bir County görüntüleyin.";
		msg2$ = "Bu noktaya büyütmek için tıklayın.";
		msg3$ = "Görüntüyü bu noktada ortalamak için tıklayın.";
		}
	} # end of OnInitialize

# Called when tool is to be destroyed, will not be called if tool was never activated.
# If the tool implements a dialog it should be destroyed here.
# proc OnDestroy () {
# } # end of OnDestroy

# Called when tool is activated.
# If the tool implements a dialog it should be "managed" (displayed) here.
# proc OnActivate () {
	### get current map scale
#	mapscale = View.GetMapScale();

#	if (mapscale > 1000000) then
#		View.SetMessage(msg1$);
#	 }  # end of OnActivate

# Called when tool is deactivated (usually when switching to another tool).
# If the tool implements a dialog it should be "unmanaged" (hidden) here.
# proc OnDeactivate () {
# }  # end of OnDeactivate

# Called when tool is to be 'suspended' during a redraw operation.
# proc OnSuspend () {
# }  # end of OnSuspend

# Called when tool is to be 'resumed' after a redraw operation.
# If the tool displays any graphics they should be updated by this function.
# proc OnResume () {
# }  # end of OnResume

# Called when user presses 'left' pointer/mouse button.
proc OnLeftButtonPress ()
	{
	local class POINT2d clickPt, clickPtTrans;	### coordinates for mouse-click position
	local numeric cntynum;			### element number of county polygon clicked in

	### get cursor position in screen coordinates
	clickPt.x = PointerX;
	clickPt.y = PointerY;

	### get current map scale
	mapscale = View.GetMapScale();

	# get TRANSPARM for coordinate transformation from screen to
	# layer coordinates for the county vector layer and convert
	# click point location to layer coordinates
	layerTransparm = View.GetTransLayerToScreen(cntyLayer, 1);
	clickPtTrans = layerTransparm.ConvertPoint2DFwd(clickPt);

	# find polygon enclosing the click point
	cntynum = FindClosestPoly(cntyVector, clickPtTrans.x, clickPtTrans.y, GetLastUsedGeorefObject(cntyVector) );


	if (mapscale > 1000000) # zoom to extents of county polygon clicked in
		{
		if (cntynum > 0)
			{
			# highlight the polygon so can zoom to it, but don't redraw yet
			cntyPolys.HighlightSingle(cntynum, "Replace", 0);

			# zoom to the highlighted polygon, redraw when unhighlight all elements
			cntyLayer.ZoomToActiveElement();
			cntyLayer.UnhighlightAllElements(1);
			lastCnty = cntynum;
			zoomedBelowCnty = 0;

			View.SetMessage(msg2$);
			}
		}

	else
		{
		if (cntynum > 0)
			{
			if (cntynum <> lastCnty && zoomedBelowCnty == 0) # if not same as last county and haven't zoomed below
				{
				# highlight the polygon so can zoom to it, but don't redraw yet
				cntyPolys.HighlightSingle(cntynum, "Replace", 0);

				# zoom to the highlighted polygon, redraw when unhighlight all elements
				cntyLayer.ZoomToActiveElement();
				cntyLayer.UnhighlightAllElements(1);
				lastCnty = cntynum;
				zoomedBelowCnty = 0;
				View.SetMessage(msg2$);
				}

			else		# click point is in same county; do variable zoom in based on scale
				{
				# get TRANSPARM for coordinate transformation from screen to view
				# coordinates and convert click point to view coordinates
				viewTransparm = View.GetTransViewToScreen(1); # inverse to get screen to view
				clickPt = viewTransparm.ConvertPoint2DFwd(clickPt);

				# reset view center to click point
				View.Center = clickPt;

				if (mapscale > 25000)	# zoom in by 4X centered on click point
					{
					View.ZoomIn(4, 1);
					zoomedBelowCnty = 1;
					View.SetMessage(msg2$);
					}

				else	# zoom to 1X centered on click point
					{
					View.Zoom1X(1);
					View.SetMessage(msg3$);
					}
				}
			}
		}
	}  # end of OnLeftButtonPress

# Called when user presses 'right' pointer/mouse button.
# proc OnRightButtonPress () {
# }  # end of OnRightButtonPress

# Called when user presses 'middle' pointer/mouse button.
# proc OnMiddleButtonPress () {
# }  # end of OnMiddleButtonPress

# Called when user releases 'left' pointer/mouse button.
# proc OnLeftButtonRelease () {
# }  # end of OnLeftButtonRelease

# Called when user releases 'right' pointer/mouse button.
# proc OnRightButtonRelease () {
# }  # end of OnRightButtonRelease

# Called when user releases 'middle' pointer/mouse button.
# proc OnMiddleButtonRelease () {
# }  # end of OnMiddleButtonRelease

# Called when user moves cursor if no button being pressed
# proc OnPointerMoveNoButton () {
# }  # end of OnPointerMoveNoButton

# Called when user moves cursor while holding down button
# proc OnPointerMoveWithButton () {
# }  # end of OnPointerMoveWithButton

# Called when cursor enters window associated with view.
 proc OnEnterWindow () {
	### get current map scale
	mapscale = View.GetMapScale();

	if (mapscale > 1000000) then
		View.SetMessage(msg1$);
	else if (mapscale > 3648) then
		View.SetMessage(msg2$);
	else
		View.SetMessage(msg3$);

 }  # end of OnEnterWindow

# Called when cursor leaves window associated with view.
# proc OnLeaveWindow () {
# }  # end of OnLeaveWindow

# Called when user presses 'key' on keyboard.
# proc OnKeyPress (key) {
# }  # end of OnKeyPress