/*
* 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 can be used to measure the average slope gradient of each link in a stream network.
*
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class StreamLinkSlope implements WhiteboxPlugin {
private WhiteboxPluginHost myHost = null;
private String[] args;
// Constants
private static final double LnOf2 = 0.693147180559945;
/**
* 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 "StreamLinkSlope";
}
/**
* 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 "Stream Link Slope";
}
/**
* Used to retrieve a short description of what the plugin tool does.
*
* @return String containing the plugin's description.
*/
@Override
public String getToolDescription() {
return "Estimates the slope of each link in a stream network.";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
*
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = { "StreamAnalysis" };
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 streamsLinkIDHeader = null;
String pointerHeader = null;
String DEMHeader = null;
String outputHeader = null;
int row, col, x, y;
float progress = 0;
int i, c;
double z;
int[] dX = new int[]{1, 1, 1, 0, -1, -1, -1, 0};
int[] dY = new int[]{-1, 0, 1, 1, 1, 0, -1, -1};
double[] inflowingVals = new double[]{16, 32, 64, 128, 1, 2, 4, 8};
boolean flag = false;
double flowDir = 0;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
for (i = 0; i < args.length; i++) {
if (i == 0) {
streamsLinkIDHeader = args[i];
} else if (i == 1) {
pointerHeader = args[i];
} else if (i == 2) {
DEMHeader = args[i];
} else if (i == 3) {
outputHeader = args[i];
}
}
// check to see that the inputHeader and outputHeader are not null.
if ((streamsLinkIDHeader == null) || (pointerHeader == null) || (outputHeader == null)) {
showFeedback("One or more of the input parameters have not been set properly.");
return;
}
try {
WhiteboxRaster streamID = new WhiteboxRaster(streamsLinkIDHeader, "r");
int rows = streamID.getNumberRows();
int cols = streamID.getNumberColumns();
double noData = streamID.getNoDataValue();
double gridResX = streamID.getCellSizeX();
double gridResY = streamID.getCellSizeY();
double diagGridRes = Math.sqrt(gridResX * gridResX + gridResY * gridResY);
double[] gridLengths = new double[]{diagGridRes, gridResX, diagGridRes, gridResY, diagGridRes, gridResX, diagGridRes, gridResY};
double maxLinkID = streamID.getMaximumValue();
double[] linkLengths = new double[(int)maxLinkID + 1];
WhiteboxRaster pntr = new WhiteboxRaster(pointerHeader, "r");
if (pntr.getNumberRows() != rows || pntr.getNumberColumns() != cols) {
showFeedback("The input images must be of the same dimensions.");
return;
}
WhiteboxRaster DEM = new WhiteboxRaster(DEMHeader, "r");
if (DEM.getNumberRows() != rows || DEM.getNumberColumns() != cols) {
showFeedback("The input images must be of the same dimensions.");
return;
}
WhiteboxRaster output = new WhiteboxRaster(outputHeader, "rw",
streamsLinkIDHeader, WhiteboxRaster.DataType.FLOAT, 0);
output.setPreferredPalette("spectrum.pal");
output.setDataScale(WhiteboxRaster.DataScale.CONTINUOUS);
double[][] linkRelief = new double[3][(int)maxLinkID + 1]; //first entry holds
//the minimum elevation, the second holds the maximimum, and the third holds the slope
//initialize the LinkRelief array so that the min and max values can be found
for (c = 0; c <= maxLinkID; c++) {
linkRelief[0][c] = 99999999;
linkRelief[1][c] = -99999999;
}
byte numNeighbouringStreamCells = 0;
double currentID = 0;
double linkLength = 0;
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
if (streamID.getValue(row, col) > 0) {
// see if it is a headwater location
numNeighbouringStreamCells = 0;
for (c = 0; c < 8; c++) {
x = col + dX[c];
y = row + dY[c];
if (streamID.getValue(y, x) > 0 &&
pntr.getValue(y, x) == inflowingVals[c]) {
numNeighbouringStreamCells++;
}
}
if (numNeighbouringStreamCells == 0) {
//it's a headwater location so start a downstream flowpath
x = col;
y = row;
linkLength = 0;
currentID = streamID.getValue(y, x);
flag = true;
do {
z = DEM.getValue(y, x);
if (z < linkRelief[0][(int)currentID]) { linkRelief[0][(int)currentID] = z; }
if (z > linkRelief[1][(int)currentID]) { linkRelief[1][(int)currentID] = z; }
//find the downslope neighbour
flowDir = pntr.getValue(y, x);
if (flowDir > 0) {
c = (int)(Math.log(flowDir) / LnOf2);
if (c > 7) {
showFeedback("An unexpected value has "
+ "been identified in the pointer "
+ "image. This tool requires a "
+ "pointer grid that has been "
+ "created using either the D8 "
+ "or Rho8 tools.");
return;
}
linkLength += gridLengths[c];
x += dX[c];
y += dY[c];
if (streamID.getValue(y, x) != currentID) {
linkLengths[(int)(currentID)] = linkLength;
currentID = streamID.getValue(y, x);
if (currentID != noData) {
linkLength = 0;
if (linkLengths[(int) currentID] > 0) {
flag = false;
}
} else {
flag = false;
}
}
} else {
linkLengths[(int)currentID] = linkLength;
flag = false;
}
} while (flag);
}
} else {
output.setValue(row, col, noData);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (float) (100f * row / (rows - 1));
updateProgress((int) progress);
}
for (i = 1; i <= maxLinkID; i++) {
linkRelief[2][i] = (linkRelief[1][i] - linkRelief[0][i]) / linkLengths[i] * 100;
}
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
if (streamID.getValue(row, col) > 0) {
currentID = streamID.getValue(row, col);
output.setValue(row, col, linkRelief[2][(int)currentID]);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (float) (100f * row / (rows - 1));
updateProgress((int) progress);
}
output.addMetadataEntry("Created by the "
+ getDescriptiveName() + " tool.");
output.addMetadataEntry("Created on " + new Date());
pntr.close();
streamID.close();
output.close();
// returning a header file string displays the image.
returnData(outputHeader);
String retData = "Stream Link Slope Output\n";
for (i = 1; i <= maxLinkID; i++) {
retData = retData + i + "\t" + linkRelief[2][i] + "\n";
}
returnData(retData);
} 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();
}
}
}