source: geovis/trunk/geovis_protocol.txt @ 6673

================================================================================
================================================================================
Protocol for geovis render server.  

Commands take the general form of command and arguments using Tcl syntax and are
terminated by a newline.  Some command arguments expect a Tcl list which can be
sent by enclosing the list in curly braces to prevent the interpreter from 
splitting the list into multiple arguments.  Likewise, strings with spaces 
should be quoted or enclosed in curly braces.  In the documentation below,
arguments are indicated by angle brackets and optional arguments are surrounded
by question marks -- the brackets and question marks are not part of the
protocol and should not be included in argument strings.  The arguments shown 
in angle brackets should be replaced with a string (where there are fixed 
choices this document indicates valid values by separating them with pipe 
symbols), a list in Tcl syntax, or a numeric value.  Boolean arguments can take
the form of 0|1, true|false, or yes|no.  Since the protocol commands are 
executed in a Tcl interpreter, Tcl code such as math expressions in expr 
commands enclosed in square brackets are also allowed.  Since the interpreter
is a "safe" interpreter, some Tcl commands that could cause security issues may 
not be available for use.

When binary data is to be sent, it should follow the newline after a command 
that indicates incoming data including a byte count argument.
================================================================================
================================================================================
Requests:
================================================================================

== General scene and renderer commands ==

camera delete <name>
       Delete named viewpoint
camera dist <distance>
       Set camera distance from focal point
camera extent <xmin> <ymin> <xmax> <ymax> <?duration?> <?srs?>
       Zoom to extent.  Will fit the extent to the vertical FOV and center on
       the extent centroid.
       <xmin>,<ymin>,<xmax>,<ymax> = extent bounds in the specified SRS,
       or in the map's SRS if none is specified.
       <duration> = Duration of viewpoint move animation in seconds
       <srs> = The SRS of the extent bounds
camera get
       Request camera parameters
camera go <x> <y> <?zoomFactor?> <?duration?>
       Move camera to new focal point.
       <x>,<y> = Screen/mouse coordinates
       <zoomFactor> = Zoom distance multiplier, 1.0=no zoom
       <duration> = Duration of viewpoint move animation in seconds
camera lextent <layerName> <?duration?>
       Zoom to layer extent.  Will fit the extent to the vertical FOV and center
       on the extent centroid.
       <layerName> = Name of layer to use for extent.
       <duration> = Duration of viewpoint move animation in seconds
camera orient <quatW> <quatX> <quatY> <quatZ>
       Set scene orientation using a quaternion
camera pan <x> <y>
       <x,y> viewport coordinates (window center at 0,0).  Positive x pan
       means pan object to right (camera to left).  Positive y pan means
       pan object down (camera up).  For example a pan of 0.5, 0.5 would
       move the object center to the lower right corner of the window
camera reset <?all?>
       Option all resets orientation/rotation as well as pan/zoom/clip range
camera restore <name> <?duration?>
       Set viewpoint to a named viewpoint, with optional animation duration in 
       seconds
camera rotate <x> <y>
       Specify relative rotation in viewport coordinates
camera save <name>
       Save current viewpoint to a named viewpoint
camera set <x> <y> <z> <heading> <pitch> <distance> <?duration?> <?srs?> <?vertDatum?>
       Explicitly set camera parameters, with optional animation duration in 
       seconds
       <x>, <y> = Map coordinates of focal point
       <z> = Altitude of focal point (see vertDatum)
       <heading> = Azimuth in degrees
       <pitch> = Elevation in degrees
       <distance> = Distance of camera from focal point in map units(?)
       <srs> = coordinate system, defaults to map coordinate system
       <vertDatum> = vertical datum for interpreting z coordinate 
camera throw <bool>
       Enable/disable throw inertia for panning/rotating when using mouse events
       through protocol
camera zoom <y>
       Specify zoom by viewport coordinates (i.e. normalized y mouse coords)

clientinfo <list>

colormap add <colorMapName> <colorMap>
         (Re-)define a colormap.  If colorMapName doesn't exist, it is created,
         otherwise the colormap is redefined and all users will be updated.
         colorMap = Tcl list of {value r g b a} control points
colormap define <colorMapName> <colorMap>
         (Re-)define a colormap (same as 'add')
colormap delete <?colorMapName?>
colormap res <numberOfTableEntries>
         Set the "resolution" or number of lookup table entries in the colormap
         <numberOfTableEntries> = integer or "default"

legend <colormapName> <w> <h> <?opaque?> <?bgR?> <?bgG?> <?bgB?>
       Render a legend colorbar.
       <colormapName> - Name of the colormap defined with the colormap command
       <w>,<h> - width and height of colorbar
       <opaque> - If false, blend with background color
       <bgR>,<bgG>,<bgB> - Background color (defaults to black)

renderer render
         Force a new image to be rendered

screen bgcolor <r> <g> <b>
screen coords <token> <coordList> <?srs?> <?verticalDatum?>
       Transate map coordinates to screen/mouse coordinates.
       <token> - String token, included in response
       <coordList> - A list of x,y,z map coordinates.  If <srs> is not given,
       these are in the map's coordinate system.
       <srs> - Optional horizontal srs init string for coordinate system of 
       x,y,z
       <verticalDatum> - Optional vertical srs init string for coordinate system
       of x,y,z
screen size <width> <height>

== Mouse and Keyboard Events ==

key press <key>
key release <key>

mouse click <button> <x> <y>
mouse dblclick <button> <x> <y>
mouse drag <button> <x> <y>
mouse motion <x> <y>
mouse release <button> <x> <y>
mouse scroll <direction>

== Interaction Configuration ==

placard config <attrlist> <style> <padding> <layerName>
    <attrlist> - List of attributes.  The list should consist of alternating
    attribute names and attribute labels.  The names are the column names of the
    attributes in the feature data and the corresponding labels will be 
    displayed on the info placard
    <style> - CSS style attributes for TextSymbol and PolygonSymbol (fill for
    backing quad)
    <padding> - Pixels of padding between text and edge of backdrop quad.
    <layerName> - The name of the layer containing the feature data.

placard enable <bool> <layerName>
    Enable/disable display of feature attribute placard on select.
    <layerName> - The name of the layer containing the feature data.

select clear
    Clear any annotation or feature selection

select fadd <featureIDList> <layerName>
    Add features to the selected set
    <featureIDList> - List of feature IDs to be selected.
    <layerName> - The name of the layer containing the feature data.

select fdelete <featureIDList> <layerName>
    Remove features from the selected set
    <featureIDList> - List of feature IDs to be selected.
    <layerName> - The name of the layer containing the feature data.

select feature <featureIDList> <layerName>
    Set/replace the set of currently selected features
    <featureIDList> - List of feature IDs to be selected.
    <layerName> - The name of the layer containing the feature data.

select mode <mode>
    <mode> - boolean: Enable/disable click to select mode.

== Map Commands ==

map attrib <string>
    <string> - Attribution/copyright to display in corner of map

map coords <token> <coordList> <?srs?> <?verticalDatum?>
    Translate screen/mouse coordinates into map coordinates.
    <token> - String token, included in response
    <coordList> - A list of x,y screen/mouse coordinates
    <srs> - Optional horizontal srs init string for coordinate system to return
    <verticalDatum> - Optional vertical srs init string for coordinate system to
    return

map grid <bool> <?type?>
    Toggle graticule and set type
    <type> = geodetic|utm|mgrs

General form:
map layer add <layerName> <type> <driver> <?url?> <?cache?> ...
    <type> = image|elevation|feature|icon|line|mask|model|point|polygon|text
    <driver> = arcgis|colorramp|db|debug|gdal|ogr|tfs|tms|wcs|wfs|wms|xyz
    <cache> = bool indicating if tiles should be cached on disk

Specific image layer types:
map layer add <layerName> image agglite <url> <cache> <coverage> <featuredriver> <format> <typeName> <styleLen> <?scriptLen?> <?selectorsLen?>
    Rasterize a feature source to an image layer using the AGGLite renderer
    <url> = URL of source
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
    <featuredriver> = Feature driver to read source (db, ogr, tfs, wfs)
    <format> = See Feature/model layers below
    <typeName> = See Feature/model layers below
    <styleLen> = See Feature/model layers below
    <scriptLen> = See Feature/model layers below
    <selectorsLen> = See Feature/model layers below
map layer add <layerName> image colorramp <url> <cache> <coverage> <elevdriver> <profile> <colormapName>
    Add a colormapped image layer from a file or URL
    <url> = URL of source
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
    <elevdriver> = Elevation driver to read source
    <profile> = profile of source
    <colormapName> = Name of colormap
map layer add <layerName> image arcgis <url> <?cache?> <?coverage?> <?token?> <?layers?>
    Add an ArcGIS MapServer image layer from a URL
    <url> = URL of source
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
    <token> = login credential
map layer add <layerName> image gdal <url> <?cache?> <?coverage?>
    Add a GDAL image layer from a file or URL
    <url> = URL of source
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
map layer add <layerName> image wms <url> <cache> <coverage> <layers> <format> <transparent> <?times?> <?frameSeconds?>
    Add a WMS image layer from a URL + layer string
    <url> = URL of WMS service
    <cache> = bool indicating if tiles may be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
    <layers> = layers string for WMS server
    <format> = Image format to return (e.g. 'png')
    <transparent> = bool
    <times> = optional comma separated list of timestamps for WMS-T
    <frameSeconds> = time in seconds to display each animated frame for WMS-T
map layer add <layerName> image tms <url> <cache> <coverage>
    Add a TMS image layer from a URL
    <url> = URL of TMS service
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)
map layer add <layerName> image xyz <urlPattern> <cache> <coverage>
    Add an image layer from a web map using a template URL
    <urlPattern> = URL template of source.  '{x}', '{y}', '{z}' will be replaced
    with tile row (x), column (y) and zoom level (z).  A block of characters in
    square braces can be used to specify round-robin server numbers, e.g.
    'host[012]' will exand to 'host0', host1', 'host2'.
    <cache> = bool indicating if tiles should be cached on disk
    <coverage> = bool indicating if data should not be interpolated (true means
    no interpolation)

Elevation layers:
map layer add <layerName> elevation <driver> <url> <?cache?> <?verticalDatum?>
    Add an elevation image layer from a file or URL
    <driver> = gdal|tms|wcs
    <verticalDatum> = override vertical datum in file.  This is required for
    the gdal driver if the vertical datum is a geoid (i.e. not geodetic HAE).

Feature/model and mask layers:
In the following:
<driver> = db|ogr|tfs|wfs
<url> = file/web service address, or for driver 'db' the postgis connection
string
<format> = json|gml (for tfs or wfs driver)
<typeName> = layer name for db or wfs driver
<clamping> = none|terrain|relative|absolute
<clamptechnique> = drape|gpu|scene|map

map layer add <layerName> feature <driver> <format> <typeName> <url> <cache> <styleLen> <?scriptLen?> <?selectorsLen?> <?terrainPatch?> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Data payload follows command: style, then script, then selectors
    <styleLen> = Number of bytes in style sheet. Stylesheet payload consists of 
    CSS-formatted styles (see:
    http://docs.osgearth.org/en/latest/user/features.html and
    http://docs.osgearth.org/en/latest/references/symbology.html)
    <scriptLen> = Number of bytes in scripts.  Scripts payload consists of
    JavaScript code (see references above)
    <selectorsLen> = Number of bytes in selectors.  Selectors payload consists
    of a Tcl list of name/value pairs
    <terrainPatch> = Boolean indicating if layer should be used for elevation
    queries.
map layer add <layerName> icon <driver> <format> <typeName> <url> <cache> <icon> <scale> <heading> <declutter> <placement> <alignment> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Add an icon feature layer from a file or URL
    <placement> = vertex|centroid|interval|random
    <alignment> = left_top|left_center|left_bottom|center_top|center_center|center_bottom|right_top|right_center|right_bottom
map layer add <layerName> line <driver> <format> <typeName> <url> <cache> <r> <g> <b> <width> <?cap?> <?join?> <?stipplePattern?> <?stippleFactor?> <?clamping?> <?clamptechnique?> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Add a line feature layer from a file or URL
    cap/join only used if width > 1
    <cap> = flat|square|round
    <join> = mitre|round
map layer add <layerName> point <driver> <format> <typeName> <url> <cache> <r> <g> <b> <size> <?clamping?> <?clamptechnique?> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Add a point feature layer from a file or URL
map layer add <layerName> polygon <driver> <format> <typeName> <url> <cache> <r> <g> <b> <?lineWidth?> <?strokeR?> <?strokeG?> <?strokeB?> <?clamping?> <?clamptechnique?> <?terrainPatch?> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Add a polygon feature layer from a file or URL
map layer add <layerName> text <driver> <format> <typeName> <url> <cache> <content> <priority> <fgR> <fgG> <fgB> <bgR> <bgG> <bgB> <haloWidth> <fontSize> <declutter> <alignment> <xoffset> <yoffset> <?visibilityRangeMin?> <?visibilityRangeMax?>
    Add a text symbol layer from a file or URL
    <alignment> = left_top|left_center|left_bottom|center_top|center_center|center_bottom|right_top|right_center|right_bottom|left_baseline|center|baseline|right_baseline|left_bottom_baseline|center_bottom_baseline|right_bottom_baseline

map layer add <layerName> mask <driver> <format> <typeName> <url> <?minLOD?>
    Create a terrain mask layer to cut a hole in the terrain geometry.  The
    first feature found is assumed to be a boundary polygon.
    <driver> = db|ogr|tfs|wfs|wkt|wkt_file
    <minLOD> minimum LOD to at which to apply the mask, defaults to 0.
map layer add <layerName> mask wkt <format> <typeName> <length> <?minLOD?>
    Like generic mask layer command, but instead of a <url>, included data in
    the payload which is a WKT literal string.
    <format> and <typeName> are unused
    <length> = length of following data for inline WKT string
map layer add <layerName> mask wkt_file <format> <typeName> <url> <?minLOD?>
    <url> = URL for a text file containing a WKT string
    <format> and <typeName> are unused

map layer add <layerName> model simple <url> <x> <y> <?z?> <?rotx?> <?roty?> <?rotz?> <?terrainPatch?>
    <url> = Path to a 3D model file that OSG can load (e.g. .osg file)
    <x>,<y>,<z> = Map coordinates for placing the model
    <rotx>,<roty>,<rotz> = Rotations (in degrees) to apply to orient model
    <terrainPatch> = boolean indicating if model should be used for elevation
    queries.

map layer delete <layerName>
map layer opacity <opacity> <layerName>
map layer move <pos> <layerName>
map layer names <?type?>
    Generates a response listing the names of the given type (or all types if
    not specified)
    <type> = elevation|image|mask|model
map layer visible <bool> <layerName>

map load data follows <nbytes>
    Send an .earth file over the wire
map load file <path>
    Load an .earth file from a filesystem mounted on the server
map load url <url>
    Load an .earth file from a network address

map posdisp <bool> <?format?> <?precision?>
    Toggle coordinate/position display, set format and precision
    <format> = latlong_decimal_degrees|latlong_degrees_decimal_minutes|
               latlong_degrees_minutes_seconds|mgrs
    <precision> = integer number of digits to display

map reset <type> <r> <g> <b> <?profile?> <?xmin?> <?ymin?> <?xmax?> <?ymax?>
    Clear the scene and rebuild a new map from scratch.  When resetting the 
    map to geocentric, a profile and extents should be omitted.  When the map
    type is projected, the profile is required and extents are optional.
    <type> = geocentric|projected
    <r>,<g>,<b> - Background color red, green and blue components [0,1]
    <profile> = Well known profile string, e.g. 'global-geodetic',
    'global-mercator'.  If specifying bounds (i.e. not global), use 'geodetic'
    or 'spherical-mercator' or an SRS init string (such as an EPSG code)
    xmin,ymin,xmax,ymax = map bounds (in profile projection/units)

map scalebar <bool> <?units?>
    Toggle scale label/bar
    <units> = meters|feet|us_survey_feet|nautical_miles
map setpos <x> <y>
    Set the coordinate/position display based on mouse coordinates
map terrain edges <bool>
    *Not currently implemented*
map terrain lighting <bool>
map terrain linecolor <r> <g> <b>
    *Not currently implemented*
map terrain vertscale <val>
    Set scale factor for terrain height
map terrain wireframe <bool>
map time <?hours?> <?day?> <?month?> <?year?>
    Set ephemeris time for sky.  When args are omitted, set to current time.
    Time is interpreted as UTC.

================================================================================
Replies:
================================================================================
nv>image -type image -bytes <nbytes>
  <binary RGB data>
nv>legend <colormapName> <rmin> <rmax> <nbytes>
  <binary RGB data>
nv>map coords <token> <mapCoordList> <?srs?> <?verticalDatum?>
   Reply to query of map coordinates from screen coordinates.  The mapCoordList
   is a list of x,y,z map coordinates.  The srs of the map coordinates may be 
   included if not in map's native coordinate system.  NaN in the results 
   indicates off-map input coordinates.
nv> map names <list>
   Reply to query of layer names.  <list> is a Tcl formatted list.
nv>screen coords <token> <screenCoordList>
   Reply to query of screen coordinates from map coordinates.  The
   screenCoordList is a list of x,y,z screen coordinates (z is the depth).  NaN
   in the results indicates a point outside the view frustum or invalid input
   map coordinate
nv>select annotation <guid> <annotationName>
nv>select clear
nv>select feature <guid> <featureIDList> <numFeatures> <layerName>
nv>select region <xmin> <ymin> <xmax> <ymax>
nv>ok -token <seqnum>
   Reply indicated commands through <seqnum> (numbered beginning at 0) have been
   processed, but no new image was rendered
================================================================================
Error Replies:
================================================================================
nv>viserror -bytes <nbytes>
   <multi-line error string of nbytes>
================================================================================