Distance Surface - Revision history

Fei at 16:56, 14 November 2006

2006-11-14T16:56:50Z

@@ Line 46: / Line 46: @@
     DistanceFromSrc[CellWidth*(NumRows^2 + NumCols^2)^0.5 + 1] <= 0
     NearestSrcLoc[-1] <= 0
 ==Suggested Experiments==
 To explore this cellular automata model further, try the following:

Fei at 16:53, 14 November 2006

2006-11-14T16:53:59Z

@@ Line 14: / Line 14: @@
 In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.
-===MLM.scn===
+===Dist2Roads.scn===
+ SELES Scenario
-===Model.sel===
+===Dist2Streams.scn===
 ==Suggested Experiments==
 To explore this cellular automata model further, try the following:

Fei at 21:46, 8 November 2006

2006-11-08T21:46:29Z

@@ Line 4: / Line 4: @@
 ==Screenshot==
-[[Image:ConvexHull.gif]]
+[[Image:DistanceSurface.gif]]
 ==Download Model==
-Download the .scn, .sel and .lse files by clicking on the following link: [[Image:ConvexHull.zip]]
+Download the .scn, .sel and .lse files by clicking on the following link: [[Image:DistanceSurface.zip]]
 ==Model Code Exploration==
@@ Line 16: / Line 16: @@
 ===MLM.scn===
-  SELES Scenario
 ===Model.sel===
 ===ConvexHull.lse===
-  // Sweep-line approach to identifying convex hull using a worker agent
 ==Suggested Experiments==
 To explore this cellular automata model further, try the following:

Fei at 21:41, 8 November 2006

2006-11-08T21:41:59Z

New page

==Summary==

==Screenshot==

[[Image:ConvexHull.gif]]

==Download Model==

Download the .scn, .sel and .lse files by clicking on the following link: [[Image:ConvexHull.zip]]

==Model Code Exploration==

In the following sections we will examine all of the model files for this model. Note that instead of downloading the zip file above, you could just copy the text in the boxes below into a text editor and save it with the appropriate name (Section title). Opening the resulting .scn file in the SELES simulator would run this model.

===MLM.scn===

SELES Scenario
$gisData$ = ..\..\CaseStudy_Morice\gisData\cell
StudyArea = $gisData$\BEC
Model Dimensions: StudyArea
Model.sel
SimPriority Low Priority
//SimStart 100000 1

===Model.sel===

Seles Model
Time Units: Step kiloStep 1000 100000
Landscape Events:
ConvexHull.lse
Spatial Constants:
StudyArea
Spatial Variables:
ConvexHullPoints[1] <= 0
ConvexHull[1] <= 0
Global Variables:
TRLoc = 0
Output Frequency: 1

===ConvexHull.lse===

// Sweep-line approach to identifying convex hull using a worker agent
LSAGENT: ConvexHull
DEFINITIONS
LAYER: StudyArea, ConvexHull, ConvexHullPoints
GLOBAL VARIABLE: TRLoc
LOCAL VARIABLE: EndingPivotLoc
AGENT VARIABLE: PivotLocation, EdgeLocation, EdgeRow, EdgeCol
ENDDEF
INITIALSTATE
INITIALSTATE = 1
// Find the top-right-most point
TRLoc = 0
OVER REGION WHOLE MAP
DECISION StudyArea > 0
TRLoc = MAX(TRLoc, Location)
ENDFN
ConvexHull = 1 // Initialize convex hull layer to all ones (will erase areas outside hull)
ENDIS
NUMAGENTS = 1 // Only need a single worker
// Start on the first pivot vertex on convex hull
AGENTLOCATION
REGION LOCATION(TRLoc)
ENDAL
PROBINIT
PROBINIT = 1
// Set up first pivot vertex, and first raster boundary location
PivotLocation = Location
EdgeRow = NUMROWS-1
EdgeCol = COL(Location)
EdgeLocation = LOCATION(EdgeRow, EdgeCol)
EndingPivotLoc = -1
ENDPI
TRANSITIONS
// Continue until we reach the ending pivot location (which is actually second time we hit the second pivot vertex,
// since the first pivot vertex gets only partially processed on first pass)
TRANSITIONS = (PivotLocation NEQ EndingPivotLoc)
ConvexHullPoints = 1
// Walk line from boundary to vertex and erase until a new pivot vertex is hit (then move there)
oldPivot = PivotLocation
hitPivot = FALSE
OVER REGION VECTOR(EdgeLocation, PivotLocation)
DECISION !hitPivot
IF (StudyArea > 0) // hit new vertex
hitPivot = TRUE
IF (EndingPivotLoc EQ -1) AND (Location NEQ PivotLocation)
EndingPivotLoc = PivotLocation
ENDFN
PivotLocation = Location
ELSE
ConvexHull = 0 // erase
ENDFN
ENDFN
// Move boundary location clockwise around outside edge of raster
IF (EdgeRow EQ NUMROWS-1) AND (EdgeCol < NUMCOLS-1)
EdgeCol = EdgeCol + 1
ELSE IF (EdgeCol EQ NUMCOLS-1) AND (EdgeRow > 0)
EdgeRow = EdgeRow - 1
ELSE IF (EdgeRow EQ 0) AND (EdgeCol > 0)
EdgeCol = EdgeCol - 1
ELSE
EdgeRow = EdgeRow + 1
ENDFN
EdgeLocation = LOCATION(EdgeRow, EdgeCol)
ENDTR
POPULATIONTIME = 1
// Move to current/new pivot location
MOVELOCATION
REGION LOCATION(PivotLocation)
ENDML

==Suggested Experiments==

To explore this cellular automata model further, try the following: