/*
* 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 calculates the average length of the flowpaths that run through each grid cell (in map horizontal units) in a flow pointer grid.
*
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class AverageUpslopeFlowpathLength 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 "AverageUpslopeFlowpathLength";
}
/**
* 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 "Average Upslope Flowpath Length";
}
/**
* Used to retrieve a short description of what the plugin tool does.
*
* @return String containing the plugin's description.
*/
@Override
public String getToolDescription() {
return "Measures the average length of all upslope flowpaths draining to each grid cell.";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
*
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = {"FlowpathTAs"};
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 row, col, x, y;
int progress = 0;
double z, val, val2;
int i, c;
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;
double flowLength = 0;
double numUpslopeFlowpaths = 0;
double flowpathLengthToAdd = 0;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
inputHeader = args[0];
outputHeader = args[1];
// 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 pntr = new WhiteboxRaster(inputHeader, "r");
int rows = pntr.getNumberRows();
int cols = pntr.getNumberColumns();
double noData = pntr.getNoDataValue();
double gridResX = pntr.getCellSizeX();
double gridResY = pntr.getCellSizeY();
double diagGridRes = Math.sqrt(gridResX * gridResX + gridResY * gridResY);
double[] gridLengths = new double[]{diagGridRes, gridResX, diagGridRes, gridResY, diagGridRes, gridResX, diagGridRes, gridResY};
WhiteboxRaster output = new WhiteboxRaster(outputHeader, "rw",
inputHeader, WhiteboxRaster.DataType.FLOAT, -999);
output.setPreferredPalette("blueyellow.pal");
output.setDataScale(WhiteboxRaster.DataScale.CONTINUOUS);
output.setZUnits(pntr.getXYUnits());
WhiteboxRaster numInflowingNeighbours = new WhiteboxRaster(outputHeader.replace(".dep",
"_temp1.dep"), "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, 0);
numInflowingNeighbours.isTemporaryFile = true;
WhiteboxRaster numUpslopeDivideCells = new WhiteboxRaster(outputHeader.replace(".dep",
"_temp2.dep"), "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, 0);
numUpslopeDivideCells.isTemporaryFile = true;
WhiteboxRaster totalFlowpathLength = new WhiteboxRaster(outputHeader.replace(".dep",
"_temp3.dep"), "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, 0);
totalFlowpathLength.isTemporaryFile = true;
updateProgress("Loop 1 of 3:", 0);
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
if (pntr.getValue(row, col) != noData) {
z = 0;
for (i = 0; i < 8; i++) {
if (pntr.getValue(row + dY[i], col + dX[i]) ==
inflowingVals[i]) { z++; }
}
if (z > 0) {
numInflowingNeighbours.setValue(row, col, z);
} else {
numInflowingNeighbours.setValue(row, col, -1);
}
} else {
output.setValue(row, col, noData);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (int) (100f * row / (rows - 1));
updateProgress("Loop 1 of 3:", progress);
}
updateProgress("Loop 2 of 3:", 0);
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
val = numInflowingNeighbours.getValue(row, col);
if (val <= 0 && val != noData) {
flag = false;
x = col;
y = row;
do {
val = numInflowingNeighbours.getValue(y, x);
if (val <= 0 && val != noData) {
//there are no more inflowing neighbours to visit; carry on downslope
if (val == -1) {
//it's the start of a flowpath
numUpslopeDivideCells.setValue(y, x, 0);
numUpslopeFlowpaths = 1;
} else {
numUpslopeFlowpaths = numUpslopeDivideCells.getValue(y, x);
}
numInflowingNeighbours.setValue(y, x, noData);
// find it's downslope neighbour
flowDir = pntr.getValue(y, x);
if (flowDir > 0) {
// what's the flow direction as an int?
c = (int) (Math.log(flowDir) / LnOf2);
flowLength = gridLengths[c];
val2 = totalFlowpathLength.getValue(y, x);
flowpathLengthToAdd = val2 + numUpslopeFlowpaths * flowLength;
//move x and y accordingly
x += dX[c];
y += dY[c];
numUpslopeDivideCells.setValue(y, x,
numUpslopeDivideCells.getValue(y, x)
+ numUpslopeFlowpaths);
totalFlowpathLength.setValue(y, x,
totalFlowpathLength.getValue(y, x)
+ flowpathLengthToAdd);
numInflowingNeighbours.setValue(y, x,
numInflowingNeighbours.getValue(y, x) - 1);
} else { // you've hit the edge or a pit cell.
flag = true;
}
} else {
flag = true;
}
} while (!flag);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (int) (100f * row / (rows - 1));
updateProgress("Loop 2 of 3:", progress);
}
numUpslopeDivideCells.flush();
totalFlowpathLength.flush();
numInflowingNeighbours.close();
updateProgress("Loop 3 of 3:", 0);
double[] data1 = null;
double[] data2 = null;
double[] data3 = null;
for (row = 0; row < rows; row++) {
data1 = numUpslopeDivideCells.getRowValues(row);
data2 = totalFlowpathLength.getRowValues(row);
data3 = pntr.getRowValues(row);
for (col = 0; col < cols; col++) {
if (data3[col] != noData) {
if (data1[col] > 0) {
val = data2[col] / data1[col];
output.setValue(row, col, val);
} else {
output.setValue(row, col, 0);
}
} else {
output.setValue(row, col, noData);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (int) (100f * row / (rows - 1));
updateProgress("Loop 3 of 3:", progress);
}
output.addMetadataEntry("Created by the "
+ getDescriptiveName() + " tool.");
output.addMetadataEntry("Created on " + new Date());
pntr.close();
numUpslopeDivideCells.close();
totalFlowpathLength.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();
}
}
}