graph improvements

android-app/src/main/java/org/solovyev/android/calculator/plot/AbstractCalculatorPlotFragment.java

@@ -15,12 +15,9 @@ import com.actionbarsherlock.app.SherlockFragmentActivity;
 import com.actionbarsherlock.view.Menu;
 import com.actionbarsherlock.view.MenuInflater;
 import com.actionbarsherlock.view.MenuItem;
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 import org.solovyev.android.Android;
 import org.solovyev.android.Threads;
 import org.solovyev.android.calculator.*;
-import org.solovyev.android.calculator.model.AndroidCalculatorEngine;
 import org.solovyev.android.menu.AMenuItem;
 import org.solovyev.android.menu.ActivityMenu;
 import org.solovyev.android.menu.IdentifiableMenuItem;
@@ -29,6 +26,8 @@ import org.solovyev.android.sherlock.menu.SherlockMenuHelper;
 import org.solovyev.common.JPredicate;
 import org.solovyev.common.msg.MessageType;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.io.File;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
@@ -38,6 +37,8 @@ import java.util.List;
 import java.util.concurrent.Executor;
 import java.util.concurrent.Executors;
 
+import static org.solovyev.android.calculator.model.AndroidCalculatorEngine.Preferences;
+
 /**
  * User: serso
  * Date: 12/30/12
@@ -66,7 +67,7 @@ public abstract class AbstractCalculatorPlotFragment extends CalculatorFragment
 	private int bgColor;
 
 	@Nonnull
-	private PlotData plotData = new PlotData(Collections.<PlotFunction>emptyList(), false, PlotBoundaries.newDefaultInstance());
+	private PlotData plotData = new PlotData(Collections.<PlotFunction>emptyList(), false, true, PlotBoundaries.newDefaultInstance());
 
 	@Nonnull
 	private ActivityMenu<Menu, MenuItem> fragmentMenu;
@@ -107,15 +108,6 @@ public abstract class AbstractCalculatorPlotFragment extends CalculatorFragment
 	@Nullable
 	protected abstract PlotBoundaries getPlotBoundaries();
 
-	@Override
-	public void onPause() {
-		PreferenceManager.getDefaultSharedPreferences(this.getActivity()).unregisterOnSharedPreferenceChangeListener(this);
-
-		savePlotBoundaries();
-
-		super.onPause();
-	}
-
 	@Override
 	public void onResume() {
 		super.onResume();
@@ -126,9 +118,18 @@ public abstract class AbstractCalculatorPlotFragment extends CalculatorFragment
 		updateChart(plotData, getSherlockActivity());
 	}
 
+	@Override
+	public void onPause() {
+		PreferenceManager.getDefaultSharedPreferences(this.getActivity()).unregisterOnSharedPreferenceChangeListener(this);
+
+		savePlotBoundaries();
+
+		super.onPause();
+	}
+
 	@Override
 	public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-		if (AndroidCalculatorEngine.Preferences.angleUnit.getKey().equals(key)) {
+		if (Preferences.angleUnit.getKey().equals(key)) {
 			updateChart(this.plotData, getSherlockActivity());
 		}
 	}
@@ -139,6 +140,7 @@ public abstract class AbstractCalculatorPlotFragment extends CalculatorFragment
 			case plot_data_changed:
 				final CalculatorEventHolder.Result result = this.lastEventHolder.apply(calculatorEventData);
 				if (result.isNewAfter()) {
+					assert data != null;
 					onNewPlotData((PlotData) data);
 				}
 				break;
@@ -164,6 +166,7 @@ public abstract class AbstractCalculatorPlotFragment extends CalculatorFragment
 					createGraphicalView(view, plotData);
 				}
 
+				assert activity != null;
 				activity.invalidateOptionsMenu();
 			}
 		});

android-app/src/main/java/org/solovyev/android/calculator/plot/CalculatorGraph2dView.java

@@ -8,9 +8,9 @@ import android.view.MotionEvent;
 import android.view.View;
 import android.widget.Scroller;
 import android.widget.ZoomButtonsController;
-import javax.annotation.Nonnull;
 import org.solovyev.common.math.Point2d;
 
+import javax.annotation.Nonnull;
 import java.text.DecimalFormat;
 import java.util.Collections;
 import java.util.List;
@@ -18,17 +18,19 @@ import java.util.List;
 public class CalculatorGraph2dView extends View implements GraphView {
 
 	/*
-	**********************************************************************
+		**********************************************************************
-	*
+		*
-	*                           CONSTANTS
+		*                           CONSTANTS
-	*
+		*
-	**********************************************************************
+		**********************************************************************
-	*/
+		*/
 	private static final int NO_TOUCH = -1;
 
 	private static final float TICKS_COUNT = 15;
 	public static final int TICK_SIZE_PXS = 3;
 
+	private static final float Y_TO_X_ADJUST_SCALE = 2f;
+
 	private static final DecimalFormat tickFormat = new DecimalFormat("##0.#####E0");
 	private static final int MAX_TICK_DIGITS = 4;
 	private static final String[] TICK_FORMATS = new String[MAX_TICK_DIGITS];
@@ -38,6 +40,7 @@ public class CalculatorGraph2dView extends View implements GraphView {
 			TICK_FORMATS[i] = "%." + i + "f";
 		}
 	}
+
 	/*
 	**********************************************************************
 	*
@@ -83,7 +86,9 @@ public class CalculatorGraph2dView extends View implements GraphView {
 	@Nonnull
 	private final GraphCalculator graphCalculator = new GraphCalculatorImpl();
 
-	private boolean mDrawn = false;
+	private boolean drawn = false;
+
+	private boolean adjustYAxis = false;
 
 	/*
 	**********************************************************************
@@ -162,12 +167,17 @@ public class CalculatorGraph2dView extends View implements GraphView {
 	public void invalidateGraphs() {
 		graphsData.clear();
 
-		if (mDrawn) {
+		if (drawn) {
-			mDrawn = false;
+			drawn = false;
 			invalidate();
 		}
 	}
 
+	@Override
+	public void setAdjustYAxis(boolean adjustYAxis) {
+		this.adjustYAxis = adjustYAxis;
+	}
+
 	public void onResume() {
 	}
 
@@ -228,7 +238,12 @@ public class CalculatorGraph2dView extends View implements GraphView {
 	}
 
 	private void drawGraph(@Nonnull Canvas canvas) {
-		mDrawn = true;
+		drawn = true;
+
+		if(adjustYAxis) {
+			adjustYAxis();
+			adjustYAxis = false;
+		}
 
 		final float graphWidth = dimensions.getGWidth();
 		final float graphHeight = dimensions.getGHeight();
@@ -300,6 +315,51 @@ public class CalculatorGraph2dView extends View implements GraphView {
 		graphsData.setLastXMax(xMax);
 	}
 
+	private void adjustYAxis() {
+		final float xMin = dimensions.getXMin();
+		final float xMax = dimensions.getXMax(xMin);
+
+		float yMax = -Float.MAX_VALUE;
+		float yMin = Float.MAX_VALUE;
+
+		graphsData.checkBoundaries(Float.MAX_VALUE, -Float.MAX_VALUE, Float.MAX_VALUE);
+
+		final List<PlotFunction> plotFunctions = graphViewHelper.getPlotFunctions();
+
+		for (int i = 0; i < plotFunctions.size(); i++) {
+			final PlotFunction plotFunction = plotFunctions.get(i);
+			final GraphData graph = graphsData.get(i);
+
+			graphCalculator.computeGraph(plotFunction.getXyFunction(), xMin, xMax, graph, graphsData, dimensions);
+
+			final float[] ys = graph.getYs();
+			for (int j = 0; j < graph.getSize(); j++) {
+				final float y = ys[j];
+				if (!Float.isNaN(y)) {
+					yMax = Math.max(yMax, y);
+					yMin = Math.min(yMin, y);
+				}
+			}
+		}
+
+		final float xDist = xMax - xMin;
+
+		yMax = Math.min(yMax, xDist);
+		yMin = Math.max(yMin, -xDist);
+
+		if (yMax - yMin > 0.00000001) {
+			final float yDist = yMax - yMin;
+			float maxYDist = Y_TO_X_ADJUST_SCALE * xDist;
+			if (yDist > maxYDist) {
+				// usually functions are symmetrical => just make a symmetry
+				yMax = yMax - yDist / 2 + maxYDist / 2;
+				yMin = yMin + yDist / 2 - maxYDist / 2;
+			}
+
+			dimensions.setYRange(yMin, yMax);
+		}
+	}
+
 	@Nonnull
 	private TickDigits drawGridAndAxis(@Nonnull Canvas canvas) {
 		final TickDigits result = new TickDigits();

android-app/src/main/java/org/solovyev/android/calculator/plot/CalculatorGraph3dView.java

@@ -203,6 +203,11 @@ public class CalculatorGraph3dView extends GLView implements GraphView {
 		//To change body of implemented methods use File | Settings | File Templates.
 	}
 
+	@Override
+	public void setAdjustYAxis(boolean adjustYAxis) {
+		// not supported
+	}
+
 	@Override
 	public void onSurfaceCreated(GL10 gl, int width, int height) {
 		gl.glDisable(GL10.GL_DITHER);

android-app/src/main/java/org/solovyev/android/calculator/plot/CalculatorPlotFragment.java

@@ -4,9 +4,10 @@ import android.graphics.Bitmap;
 import android.graphics.Color;
 import android.view.View;
 import android.view.ViewGroup;
+import org.solovyev.android.calculator.R;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import org.solovyev.android.calculator.R;
 
 /**
  * User: serso
@@ -50,6 +51,7 @@ public class CalculatorPlotFragment extends AbstractCalculatorPlotFragment {
 		final PlotBoundaries boundaries = plotData.getBoundaries();
 		graphView.setXRange(boundaries.getXMin(), boundaries.getXMax());
 		graphView.setYRange(boundaries.getYMin(), boundaries.getYMax());
+		graphView.setAdjustYAxis(plotData.isAdjustYAxis());
 
 		graphView.setPlotFunctions(plotData.getFunctions());
 

android-app/src/main/java/org/solovyev/android/calculator/plot/GraphView.java

@@ -38,17 +38,5 @@ public interface GraphView extends ZoomButtonsController.OnZoomListener, TouchHa
 
 	void invalidateGraphs();
 
-/*	void increaseDensity();
+	void setAdjustYAxis(boolean adjustYAxis);
-	void decreaseDensity();*/
-
-	/*
-	**********************************************************************
-	*
-	*                           CUSTOMIZATION
-	*
-	**********************************************************************
-	*/
-
-/*    void setBgColor(int color);
-    void setAxisColor(int color);*/
 }

core/src/main/java/org/solovyev/android/calculator/plot/CalculatorPlotterImpl.java

@@ -31,6 +31,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 	private final PlotResourceManager resourceManager = new MapPlotResourceManager();
 
 	private boolean plot3d = false;
+	private boolean adjustYAxis = true;
 
 	private boolean plotImag = false;
 
@@ -40,7 +41,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 	private PlotBoundaries plotBoundaries = PlotBoundaries.newDefaultInstance();
 
 	@Nonnull
-	private PlotData plotData = new PlotData(Collections.<PlotFunction>emptyList(), plot3d, plotBoundaries);
+	private PlotData plotData = new PlotData(Collections.<PlotFunction>emptyList(), plot3d, true, plotBoundaries);
 
 	public CalculatorPlotterImpl(@Nonnull Calculator calculator) {
 		this.calculator = calculator;
@@ -308,6 +309,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 		if (functions.isEmpty()) {
 			// no functions => new plot => default boundaries
 			this.plotBoundaries = PlotBoundaries.newDefaultInstance();
+			this.adjustYAxis = true;
 		}
 
 		arity = maxArity;
@@ -378,7 +380,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 	}
 
 	private void updatePlotData() {
-		plotData = new PlotData(getVisibleFunctions(), plot3d, plotBoundaries);
+		plotData = new PlotData(getVisibleFunctions(), plot3d, adjustYAxis, plotBoundaries);
 	}
 
 	@Override
@@ -395,6 +397,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 	public void savePlotBoundaries(@Nonnull PlotBoundaries plotBoundaries) {
 		if (!this.plotBoundaries.equals(plotBoundaries)) {
 			this.plotBoundaries = plotBoundaries;
+			this.adjustYAxis = false;
 			updatePlotData();
 		}
 	}
@@ -403,6 +406,7 @@ public class CalculatorPlotterImpl implements CalculatorPlotter {
 	public void setPlotBoundaries(@Nonnull PlotBoundaries plotBoundaries) {
 		if (!this.plotBoundaries.equals(plotBoundaries)) {
 			this.plotBoundaries = plotBoundaries;
+			this.adjustYAxis = false;
 			firePlotDataChangedEvent();
 		}
 	}

core/src/main/java/org/solovyev/android/calculator/plot/PlotData.java

@@ -12,18 +12,22 @@ import java.util.List;
 public class PlotData {
 
 	@Nonnull
-	private List<PlotFunction> functions;
+	private final List<PlotFunction> functions;
 
-	private boolean plot3d;
+	private final boolean plot3d;
+
+	private final boolean adjustYAxis;
 
 	@Nonnull
-	private PlotBoundaries boundaries;
+	private final PlotBoundaries boundaries;
 
 	public PlotData(@Nonnull List<PlotFunction> functions,
 					boolean plot3d,
+					boolean adjustYAxis,
 					@Nonnull PlotBoundaries boundaries) {
 		this.functions = functions;
 		this.plot3d = plot3d;
+		this.adjustYAxis = adjustYAxis;
 		this.boundaries = boundaries;
 	}
 
@@ -40,4 +44,8 @@ public class PlotData {
 	public PlotBoundaries getBoundaries() {
 		return boundaries;
 	}
+
+	public boolean isAdjustYAxis() {
+		return adjustYAxis;
+	}
 }