/*
* Copyright (C) 2014 Jan Seibert (jan.seibert@geo.uzh.ch) and
* Marc Vis (marc.vis@geo.uzh.ch)
*
* 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.geospatialfiles.WhiteboxRasterBase;
import whitebox.interfaces.WhiteboxPlugin;
import whitebox.interfaces.WhiteboxPluginHost;
/**
* This tool can be used to calculate the downslope index described by Hjerdt et al. (2004).
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class DownslopeIndex_Radius 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 "DownslopeIndex_Radius";
}
/**
* 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 "Downslope Index (Radius)";
}
/**
* Used to retrieve a short description of what the plugin tool does.
* @return String containing the plugin's description.
*/
@Override
public String getToolDescription() {
return "Calculates the downslope index (radius) of Hjerdt et al. (WRR 2004)";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = { "FlowpathTAs", "RelativeLandscapePosition" };
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 demHeader = null;
String outputHeader = null;
float d = 0;
int maxRadius = 0;
String outputType = null;
boolean useLowest = false;
WhiteboxRaster dem;
WhiteboxRaster output;
int numCols, numRows;
double gridRes = 1;
int x = 0, y = 0, row, col, i, j;
double elevationAB, elevationXY;
int radius;
double distance;
double heightDiff;
double tmpDistance;
double tmpHeightDiff;
boolean downslope;
double noData;
float progress = 0;
double rad2deg = 180 / Math.PI;
int minX = 0, minY = 0;
double minElev = 0;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
for (i = 0; i < args.length; i++) {
if (i == 0) {
demHeader = args[i];
} else if (i == 1) {
outputHeader = args[i];
} else if (i == 2) {
d = Float.parseFloat(args[i]);
} else if (i == 3) {
maxRadius = Integer.parseInt(args[i]);
} else if (i == 4) {
outputType = args[i].toLowerCase();
} else if (i == 5) {
useLowest = Boolean.parseBoolean(args[i]);
}
}
// check to see that the inputHeader and outputHeader are not null.
if ((demHeader == null) || (outputHeader == null)) {
showFeedback("One or more of the input parameters have not been set properly.");
return;
}
try {
dem = new WhiteboxRaster(demHeader, "r");
numRows = dem.getNumberRows();
numCols = dem.getNumberColumns();
noData = dem.getNoDataValue();
gridRes = dem.getCellSizeX();
output = new WhiteboxRaster(outputHeader, "rw", demHeader, WhiteboxRaster.DataType.FLOAT, noData);
output.setPreferredPalette("blueyellow.pal");
output.setDataScale(WhiteboxRasterBase.DataScale.CONTINUOUS);
output.setZUnits("dimensionless");
// If useLowest is true, then find the minimum raster value and corresponding coordinates
updateProgress("Loop 1 of 2:", 0);
if (useLowest) {
for (row = 0; row < numRows; row++) {
for (col = 0; col < numCols; col++) {
if (dem.getValue(row, col) == dem.getMinimumValue()) {
minX = col;
minY = row;
minElev = dem.getValue(row, col);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (float) (100f * row / (numRows - 1));
updateProgress("Loop 1 of 2:", (int) progress);
}
}
// For each cell, find the closest cell whose elevation is at least 'd' units lower.
// In case multiple cells can be found within the same radius, take the one with the steepest gradient.
updateProgress("Loop 2 of 2:", 0);
for (row = 0; row < numRows; row++) {
for (col = 0; col < numCols; col++) {
radius = 0;
downslope = false;
heightDiff = 0;
distance = Float.MAX_VALUE;
elevationAB = dem.getValue(row, col);
if ((elevationAB != noData) && (elevationAB > dem.getMinimumValue() + d)) {
do {
radius = radius + 1;
for (i = -radius; i <= radius; i++) {
for (j = -radius; j <= radius; j++) {
if (Math.abs(i) > radius - 1 || Math.abs(j) > radius - 1) {
x = col + i;
y = row + j;
elevationXY = dem.getValue(y, x);
if (elevationXY != noData) {
if (elevationAB - elevationXY > d) {
tmpDistance = Math.sqrt(i * i + j * j) * gridRes;
tmpHeightDiff = elevationAB - elevationXY;
if (tmpDistance < distance) {
downslope = true;
distance = tmpDistance;
heightDiff = tmpHeightDiff;
}
}
}
}
}
}
} while ((radius < maxRadius) & (downslope == false));
// Compute the output value
if (downslope == true) {
switch (outputType) {
case "tangent":
output.setValue(row, col, heightDiff / distance);
break;
case "degrees":
output.setValue(row, col, Math.atan(heightDiff / distance) * rad2deg);
break;
case "radians":
output.setValue(row, col, Math.atan(heightDiff / distance));
break;
case "distance":
output.setValue(row, col, distance);
break;
}
} else if (useLowest == true) {
distance = Math.sqrt(Math.pow((col - minX), 2) + Math.pow((row - minY), 2)) * gridRes;
heightDiff = elevationAB - minElev;
switch (outputType) {
case "tangent":
output.setValue(row, col, heightDiff / distance);
break;
case "degrees":
output.setValue(row, col, Math.atan(heightDiff / distance) * rad2deg);
break;
case "radians":
output.setValue(row, col, Math.atan(heightDiff / distance));
break;
case "distance":
output.setValue(row, col, distance);
break;
}
}
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (float) (100f * row / (numRows - 1));
updateProgress("Loop 2 of 2:", (int) 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 (Exception e) {
showFeedback(e.getMessage());
} finally {
updateProgress("Progress: ", 0);
// tells the main application that this process is completed.
amIActive = false;
myHost.pluginComplete();
}
}
}