/*
* Copyright (C) 2011-2012 Dr. John Lindsay <jlindsay@uoguelph.ca>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package plugins;
import java.util.Date;
import whitebox.geospatialfiles.WhiteboxRaster;
import whitebox.interfaces.WhiteboxPlugin;
import whitebox.interfaces.WhiteboxPluginHost;
/**
* This tool creates a new raster in which each grid cell is assigned the distance, in meters, to the nearest topographic obstacle in a specified direction.
*
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class FetchAnalysis implements WhiteboxPlugin {
private WhiteboxPluginHost myHost = null;
private String[] args;
/**
* Used to retrieve the plugin tool's name. This is a short, unique name
* containing no spaces.
*
* @return String containing plugin name.
*/
@Override
public String getName() {
return "FetchAnalysis";
}
/**
* Used to retrieve the plugin tool's descriptive name. This can be a longer
* name (containing spaces) and is used in the interface to list the tool.
*
* @return String containing the plugin descriptive name.
*/
@Override
public String getDescriptiveName() {
return "Fetch Analysis";
}
/**
* Used to retrieve a short description of what the plugin tool does.
*
* @return String containing the plugin's description.
*/
@Override
public String getToolDescription() {
return "Performs an analysis of fetch or upwind distance to an obstacle.";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
*
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = { "WindRelatedTAs" };
return ret;
}
/**
* Sets the WhiteboxPluginHost to which the plugin tool is tied. This is the
* class that the plugin will send all feedback messages, progress updates,
* and return objects.
*
* @param host The WhiteboxPluginHost that called the plugin tool.
*/
@Override
public void setPluginHost(WhiteboxPluginHost host) {
myHost = host;
}
/**
* Used to communicate feedback pop-up messages between a plugin tool and
* the main Whitebox user-interface.
*
* @param feedback String containing the text to display.
*/
private void showFeedback(String message) {
if (myHost != null) {
myHost.showFeedback(message);
} else {
System.out.println(message);
}
}
/**
* Used to communicate a return object from a plugin tool to the main
* Whitebox user-interface.
*
* @return Object, such as an output WhiteboxRaster.
*/
private void returnData(Object ret) {
if (myHost != null) {
myHost.returnData(ret);
}
}
private int previousProgress = 0;
private String previousProgressLabel = "";
/**
* Used to communicate a progress update between a plugin tool and the main
* Whitebox user interface.
*
* @param progressLabel A String to use for the progress label.
* @param progress Float containing the progress value (between 0 and 100).
*/
private void updateProgress(String progressLabel, int progress) {
if (myHost != null && ((progress != previousProgress) ||
(!progressLabel.equals(previousProgressLabel)))) {
myHost.updateProgress(progressLabel, progress);
}
previousProgress = progress;
previousProgressLabel = progressLabel;
}
/**
* Used to communicate a progress update between a plugin tool and the main
* Whitebox user interface.
*
* @param progress Float containing the progress value (between 0 and 100).
*/
private void updateProgress(int progress) {
if (myHost != null && progress != previousProgress) {
myHost.updateProgress(progress);
}
previousProgress = progress;
}
/**
* Sets the arguments (parameters) used by the plugin.
*
* @param args An array of string arguments.
*/
@Override
public void setArgs(String[] args) {
this.args = args.clone();
}
private boolean cancelOp = false;
/**
* Used to communicate a cancel operation from the Whitebox GUI.
*
* @param cancel Set to true if the plugin should be canceled.
*/
@Override
public void setCancelOp(boolean cancel) {
cancelOp = cancel;
}
private void cancelOperation() {
showFeedback("Operation cancelled.");
updateProgress("Progress: ", 0);
}
private boolean amIActive = false;
/**
* Used by the Whitebox GUI to tell if this plugin is still running.
*
* @return a boolean describing whether or not the plugin is actively being
* used.
*/
@Override
public boolean isActive() {
return amIActive;
}
/**
* Used to execute this plugin tool.
*/
@Override
public void run() {
amIActive = true;
String inputHeader = null;
String outputHeader = null;
int i;
int progress;
int row, col;
double z = 0;
double gridRes = 0;
double currentVal = 0;
double maxValDist = 0;
double maxDist = 0;
double lineSlope = 0;
double azimuth = 0;
double deltaX = 0;
double deltaY = 0;
double x = 0;
int x1 = 0;
int x2 = 0;
double y = 0;
int y1 = 0;
int y2 = 0;
double z1 = 0;
double z2 = 0;
double dist = 0;
double oldDist = 0;
double yIntercept = 0;
int xStep = 0;
int yStep = 0;
double noData = 0;
boolean flag = false;
double heightIncrement = 0;
double currentMaxVal = 0;
maxDist = Double.MAX_VALUE;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
for (i = 0; i < args.length; i++) {
if (i == 0) {
inputHeader = args[i];
} else if (i == 1) {
outputHeader = args[i];
} else if (i == 2) {
azimuth = Double.parseDouble(args[i]);
if (azimuth > 360 || azimuth < 0) {
azimuth = 0.1;
}
if (azimuth == 0) { azimuth = 0.1; }
if (azimuth == 180) { azimuth = 179.9; }
if (azimuth == 360) { azimuth = 359.9; }
if (azimuth < 180) {
lineSlope = Math.tan(Math.toRadians(90 - azimuth));
} else {
lineSlope = Math.tan(Math.toRadians(270 - azimuth));
}
} else if (i == 3) {
heightIncrement = Double.parseDouble(args[i]);
}
}
// check to see that the inputHeader and outputHeader are not null.
if ((inputHeader == null) || (outputHeader == null)) {
showFeedback("One or more of the input parameters have not been set properly.");
return;
}
try {
WhiteboxRaster DEM = new WhiteboxRaster(inputHeader, "r");
int rows = DEM.getNumberRows();
int cols = DEM.getNumberColumns();
noData = DEM.getNoDataValue();
gridRes = (DEM.getCellSizeX() + DEM.getCellSizeY()) / 2;
WhiteboxRaster output = new WhiteboxRaster(outputHeader, "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, noData);
output.setPreferredPalette("grey.pal");
if (azimuth > 0 && azimuth <= 90) {
xStep = 1;
yStep = 1;
} else if (azimuth <= 180) {
xStep = 1;
yStep = -1;
} else if (azimuth <= 270) {
xStep = -1;
yStep = -1;
} else {
xStep = -1;
yStep = 1;
}
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
currentVal = DEM.getValue(row, col);
if (currentVal != noData) {
//calculate the y intercept of the line equation
yIntercept = -row - lineSlope * col;
//find all of the vertical intersections
currentMaxVal = 0;
maxValDist = 0;
x = col;
flag = true;
do {
x = x + xStep;
if (x < 0 || x >= cols) {
flag = false;
break;
}
//calculate the Y value
y = (lineSlope * x + yIntercept) * -1;
if (y < 0 || y >= rows) {
flag = false;
break;
}
//calculate the distance
deltaX = (x - col) * gridRes;
deltaY = (y - row) * gridRes;
dist = Math.sqrt(deltaX * deltaX + deltaY * deltaY);
if (dist > maxDist) {
flag = false;
break;
}
//estimate z
y1 = (int)(y);
y2 = y1 + yStep * -1;
z1 = DEM.getValue(y1, (int)x);
z2 = DEM.getValue(y2, (int)x);
z = z1 + (y - y1) * (z2 - z1);
if (z >= currentVal + dist * heightIncrement) {
maxValDist = dist;
flag = false;
}
} while (flag);
oldDist = dist;
//find all of the horizontal intersections
y = -row;
flag = true;
do {
y = y + yStep;
if (-y < 0 || -y >= rows) {
flag = false;
break;
}
//calculate the X value
x = (y - yIntercept) / lineSlope;
if (x < 0 || x >= cols) {
flag = false;
break;
}
//calculate the distance
deltaX = (x - col) * gridRes;
deltaY = (-y - row) * gridRes;
dist = Math.sqrt(deltaX * deltaX + deltaY * deltaY);
if (dist > maxDist) {
flag = false;
break;
}
//estimate z
x1 = (int)x;
x2 = x1 + xStep;
if (x2 < 0 || x2 >= cols) {
flag = false;
break;
}
z1 = DEM.getValue((int)-y, x1);
z2 = DEM.getValue((int)y, x2);
z = z1 + (x - x1) * (z2 - z1);
if (z >= currentVal + dist * heightIncrement) {
if (dist < maxValDist || maxValDist == 0) {
maxValDist = dist;
}
flag = false;
}
} while (flag);
if (maxValDist == 0) {
//find the larger of dist and olddist
if (dist > oldDist) {
maxValDist = -dist;
} else {
maxValDist = -oldDist;
}
}
output.setValue(row, col, maxValDist);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (int)(100f * row / (rows - 1));
updateProgress(progress);
}
output.addMetadataEntry("Created by the "
+ getDescriptiveName() + " tool.");
output.addMetadataEntry("Created on " + new Date());
DEM.close();
output.close();
// returning a header file string displays the image.
returnData(outputHeader);
} catch (OutOfMemoryError oe) {
myHost.showFeedback("An out-of-memory error has occurred during operation.");
} catch (Exception e) {
myHost.showFeedback("An error has occurred during operation. See log file for details.");
myHost.logException("Error in " + getDescriptiveName(), e);
} finally {
updateProgress("Progress: ", 0);
// tells the main application that this process is completed.
amIActive = false;
myHost.pluginComplete();
}
}
}