/*
* 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 is used to generate a flow pointer grid (i.e., flow direction) using the D-infinity (Tarboton, 1997) algorithm.
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class FlowPointerDinf 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 "FlowPointerDinf";
}
/**
* 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 "D-infinity Flow Pointer";
}
/**
* 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 a D-infinity flow direction (pointer) operation on a specified DEM.";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = { "FlowPointers" };
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;
float progress = 0;
double slope;
double z, z2;
int i, a;
//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 dist;
double gridRes;
double diagGridRes;
double maxSlope;
double flowDir = 0;
double e0;
double af;
double ac;
double e1, r, s1, s2, s, e2;
int[] acVals = new int[]{0, 1, 1, 2, 2, 3, 3, 4};
int[] afVals = new int[]{1, -1, 1, -1, 1, -1, 1, -1};
int[] e1Col = new int[]{1, 0, 0, -1, -1, 0, 0, 1};
int[] e1Row = new int[]{0, -1, -1, 0, 0, 1, 1, 0};
int[] e2Col = new int[]{1, 1, -1, -1, -1, -1, 1, 1};
int[] e2Row = new int[]{-1, -1, -1, -1, 1, 1, 1, 1};
double atanof1 = Math.atan(1);
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];
}
}
// 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();
double noData = DEM.getNoDataValue();
gridRes = DEM.getCellSizeX();
diagGridRes = gridRes * Math.sqrt(2);
WhiteboxRaster output = new WhiteboxRaster(outputHeader, "rw",
inputHeader, WhiteboxRaster.DataType.FLOAT, noData);
output.setPreferredPalette("circular_bw.pal");
output.setDataScale(WhiteboxRaster.DataScale.CONTINUOUS);
output.setZUnits("degrees");
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
e0 = DEM.getValue(row, col);
if (e0 != noData) {
maxSlope = -9999999;
flowDir = 360;
for (a = 0; a < 8; a++) {
ac = acVals[a];
af = afVals[a];
e1 = DEM.getValue(row + e1Row[a], col + e1Col[a]);
e2 = DEM.getValue(row + e2Row[a], col + e2Col[a]);
if (e1 != noData && e2 != noData) {
if (e0 > e1 && e0 > e2) {
s1 = (e0 - e1) / gridRes;
if (s1 == 0) { s1 = 0.00001; }
s2 = (e1 - e2) / gridRes;
r = Math.atan(s2 / s1);
s = Math.sqrt(s1 * s1 + s2 * s2);
if (s1 < 0 && s2 < 0) { s = -1 * s; }
if (s1 < 0 && s2 == 0) { s = -1 * s; }
if (s1 == 0 && s2 < 0) { s = -1 * s; }
if (s1 == 0.001 && s2 < 0) { s = -1 * s; }
if (r < 0 || r > atanof1) {
if (r < 0) {
r = 0;
s = s1;
} else {
r = atanof1;
s = (e0 - e2) / diagGridRes;
}
}
if (s >= maxSlope && s != 0.00001) {
maxSlope = s;
flowDir = af * r + ac * (Math.PI / 2);
}
} else if (e0 > e1 || e0 > e2) {
if (e0 > e1) {
r = 0;
s = (e0 - e1) / gridRes;
} else {
r = atanof1;
s = (e0 - e2) / diagGridRes;
}
if (s >= maxSlope && s != 0.00001) {
maxSlope = s;
flowDir = af * r + ac * (Math.PI / 2);
}
}
}
}
if (maxSlope <= 0) {
output.setValue(row, col, -1);
} else {
flowDir = Math.round((flowDir * (180 / Math.PI)) * 10) / 10;
flowDir = 360 - flowDir + 90;
if (flowDir > 360) { flowDir = flowDir - 360; }
output.setValue(row, col, flowDir);
}
} else {
output.setValue(row, col, noData);
}
}
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());
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();
}
}
}