All Downloads are FREE. Search and download functionalities are using the official Maven repository.

eu.hansolo.steelseries.tools.ConicalGradientPaint Maven / Gradle / Ivy

Go to download

The SteelSeries is a javabeans component library that contains gauges. You will find linear and radial gauges. In addition you will also find digital displays, indicators from cars and some instruments from airplanes and sailboats.

There is a newer version: 3.9.30
Show newest version
package eu.hansolo.steelseries.tools;


/**
 * A paint class that creates conical gradients around a given center point
 * It could be used in the same way as LinearGradientPaint and RadialGradientPaint
 * and follows the same syntax.
 * You could use floats from 0.0 to 1.0 for the fractions which is standard but it's
 * also possible to use angles from 0.0 to 360 degrees which is most of the times
 * much easier to handle.
 * Gradients always start at the top with a clockwise direction and you could
 * rotate the gradient around the center by given offset.
 * The offset could also be defined from -0.5 to +0.5 or -180 to +180 degrees.
 * If you would like to use degrees instead of values from 0 to 1 you have to use
 * the full constructor and set the USE_DEGREES variable to true
 * @version 1.0
 * @author hansolo
 */
public final class ConicalGradientPaint implements java.awt.Paint
{
    private final java.awt.geom.Point2D CENTER;
    private final double[] FRACTION_ANGLES;
    private final double[] RED_STEP_LOOKUP;
    private final double[] GREEN_STEP_LOOKUP;
    private final double[] BLUE_STEP_LOOKUP;
    private final double[] ALPHA_STEP_LOOKUP;
    private final java.awt.Color[] COLORS;
    private static final float INT_TO_FLOAT_CONST = 1f / 255f;

    /**
     * Standard constructor which takes the FRACTIONS in values from 0.0f to 1.0f
     * @param CENTER
     * @param GIVEN_FRACTIONS
     * @param GIVEN_COLORS
     * @throws IllegalArgumentException
     */
    public ConicalGradientPaint(final java.awt.geom.Point2D CENTER, final float[] GIVEN_FRACTIONS, final java.awt.Color[] GIVEN_COLORS) throws IllegalArgumentException
    {
        this(false, CENTER, 0.0f, GIVEN_FRACTIONS, GIVEN_COLORS);
    }

    /**
     * Enhanced constructor which takes the FRACTIONS in degress from 0.0f to 360.0f and
     * also an GIVEN_OFFSET in degrees around the rotation CENTER
     * @param USE_DEGREES
     * @param CENTER
     * @param GIVEN_OFFSET
     * @param GIVEN_FRACTIONS
     * @param GIVEN_COLORS
     * @throws IllegalArgumentException
     */
    public ConicalGradientPaint(final boolean USE_DEGREES, final java.awt.geom.Point2D CENTER, final float GIVEN_OFFSET, final float[] GIVEN_FRACTIONS, final java.awt.Color[] GIVEN_COLORS) throws IllegalArgumentException
    {
        // Check that fractions and colors are of the same size
        if (GIVEN_FRACTIONS.length != GIVEN_COLORS.length)
        {
            throw new IllegalArgumentException("Fractions and colors must be equal in size");
        }

        final java.util.ArrayList FRACTION_LIST = new java.util.ArrayList(GIVEN_FRACTIONS.length);
        final float OFFSET;
        if (USE_DEGREES)
        {
            final double DEG_FRACTION = 1f / 360f;
            if (Double.compare((GIVEN_OFFSET * DEG_FRACTION), -0.5) == 0)
            {
                OFFSET = -0.5f;
            }
            else if (Double.compare((GIVEN_OFFSET * DEG_FRACTION), 0.5) == 0)
            {
                OFFSET = 0.5f;
            }
            else
            {
                OFFSET = (float) (GIVEN_OFFSET * DEG_FRACTION);
            }
            for (float fraction : GIVEN_FRACTIONS)
            {
                FRACTION_LIST.add((float) (fraction * DEG_FRACTION));
            }
        }
        else
        {
            // Now it seems to work with rotation of 0.5f, below is the old code to correct the problem
//            if (GIVEN_OFFSET == -0.5)
//            {
//                // This is needed because of problems in the creation of the Raster
//                // with a angle offset of exactly -0.5
//                OFFSET = -0.49999f;
//            }
//            else if (GIVEN_OFFSET == 0.5)
//            {
//                // This is needed because of problems in the creation of the Raster
//                // with a angle offset of exactly +0.5
//                OFFSET = 0.499999f;
//            }
//            else
            {
                OFFSET = GIVEN_OFFSET;
            }
            for (float fraction : GIVEN_FRACTIONS)
            {
                FRACTION_LIST.add(fraction);
            }
        }
        
        // Check for valid offset
        if (OFFSET > 0.5f || OFFSET < -0.5f)
        {
            throw new IllegalArgumentException("Offset has to be in the range of -0.5 to 0.5");
        }

        // Adjust fractions and colors array in the case where startvalue != 0.0f and/or endvalue != 1.0f
        final java.util.List COLOR_LIST = new java.util.ArrayList(GIVEN_COLORS.length);
        COLOR_LIST.addAll(java.util.Arrays.asList(GIVEN_COLORS));

        // Assure that fractions start with 0.0f
        if (FRACTION_LIST.get(0) != 0.0f)
        {
            FRACTION_LIST.add(0, 0.0f);
            final java.awt.Color TMP_COLOR = COLOR_LIST.get(0);
            COLOR_LIST.add(0, TMP_COLOR);
        }

        // Assure that fractions end with 1.0f
        if (FRACTION_LIST.get(FRACTION_LIST.size() - 1) != 1.0f)
        {
            FRACTION_LIST.add(1.0f);
            COLOR_LIST.add(GIVEN_COLORS[0]);
        }

        // Recalculate the fractions and colors with the given offset
        final java.util.Map FRACTION_COLORS = recalculate(FRACTION_LIST, COLOR_LIST, OFFSET);

        // Clear the original FRACTION_LIST and COLOR_LIST
        FRACTION_LIST.clear();
        COLOR_LIST.clear();

        // Sort the hashmap by fraction and add the values to the FRACION_LIST and COLOR_LIST
        final java.util.SortedSet SORTED_FRACTIONS= new java.util.TreeSet(FRACTION_COLORS.keySet());
        final java.util.Iterator ITERATOR = SORTED_FRACTIONS.iterator();
        while (ITERATOR.hasNext())
        {
            final float CURRENT_FRACTION = ITERATOR.next();
            FRACTION_LIST.add(CURRENT_FRACTION);
            COLOR_LIST.add(FRACTION_COLORS.get(CURRENT_FRACTION));
        }

        // Set the values
        this.CENTER = CENTER;
        COLORS = COLOR_LIST.toArray(new java.awt.Color[]{});

        // Prepare lookup table for the angles of each fraction
        final int MAX_FRACTIONS = FRACTION_LIST.size();
        this.FRACTION_ANGLES = new double[MAX_FRACTIONS];
        for (int i = 0 ; i < MAX_FRACTIONS ; i++)
        {
            FRACTION_ANGLES[i] = FRACTION_LIST.get(i) * 360;
        }

        // Prepare lookup tables for the color stepsize of each color
        RED_STEP_LOOKUP = new double[COLORS.length];
        GREEN_STEP_LOOKUP = new double[COLORS.length];
        BLUE_STEP_LOOKUP = new double[COLORS.length];
        ALPHA_STEP_LOOKUP = new double[COLORS.length];

        for (int i = 0 ; i < (COLORS.length - 1) ; i++)
        {
            RED_STEP_LOOKUP[i] = ((COLORS[i + 1].getRed() - COLORS[i].getRed()) * INT_TO_FLOAT_CONST) / (FRACTION_ANGLES[i + 1] - FRACTION_ANGLES[i]);
            GREEN_STEP_LOOKUP[i] = ((COLORS[i + 1].getGreen() - COLORS[i].getGreen()) * INT_TO_FLOAT_CONST) / (FRACTION_ANGLES[i + 1] - FRACTION_ANGLES[i]);
            BLUE_STEP_LOOKUP[i] = ((COLORS[i + 1].getBlue() - COLORS[i].getBlue()) * INT_TO_FLOAT_CONST) / (FRACTION_ANGLES[i + 1] - FRACTION_ANGLES[i]);
            ALPHA_STEP_LOOKUP[i] = ((COLORS[i + 1].getAlpha() - COLORS[i].getAlpha()) * INT_TO_FLOAT_CONST) / (FRACTION_ANGLES[i + 1] - FRACTION_ANGLES[i]);
        }
    }

    /**
     * Recalculates the fractions in the FRACTION_LIST and their associated colors in the COLOR_LIST with a given OFFSET.
     * Because the conical gradients always starts with 0 at the top and clockwise direction
     * you could rotate the defined conical gradient from -180 to 180 degrees which equals values from -0.5 to +0.5
     * @param FRACTION_LIST
     * @param COLOR_LIST
     * @param OFFSET
     * @return Hashmap that contains the recalculated fractions and colors after a given rotation
     */
    private java.util.HashMap recalculate(final java.util.List FRACTION_LIST, final java.util.List COLOR_LIST, final float OFFSET)
    {
        // Recalculate the fractions and colors with the given offset
        final int MAX_FRACTIONS = FRACTION_LIST.size();
        final java.util.HashMap FRACTION_COLORS = new java.util.HashMap(MAX_FRACTIONS);
        for (int i = 0 ; i < MAX_FRACTIONS ; i++)
        {
            // Add offset to fraction
            final float TMP_FRACTION = FRACTION_LIST.get(i) + OFFSET;

            // Color related to current fraction
            final java.awt.Color TMP_COLOR = COLOR_LIST.get(i);

            // Check each fraction for limits (0...1)
            if (TMP_FRACTION <= 0)
            {
                FRACTION_COLORS.put(1.0f + TMP_FRACTION + 0.0001f, TMP_COLOR);

                final float NEXT_FRACTION;
                final java.awt.Color NEXT_COLOR;
                if (i < MAX_FRACTIONS - 1)
                {
                    NEXT_FRACTION = FRACTION_LIST.get(i + 1) + OFFSET;
                    NEXT_COLOR = COLOR_LIST.get(i + 1);
                }
                else
                {
                    NEXT_FRACTION = 1 - FRACTION_LIST.get(0) + OFFSET;
                    NEXT_COLOR = COLOR_LIST.get(0);
                }
                if (NEXT_FRACTION > 0)
                {
                    final java.awt.Color NEW_FRACTION_COLOR = getColorFromFraction(TMP_COLOR, NEXT_COLOR, (int) ((NEXT_FRACTION - TMP_FRACTION) * 10000), (int) ((-TMP_FRACTION) * 10000));
                    FRACTION_COLORS.put(0.0f, NEW_FRACTION_COLOR);
                    FRACTION_COLORS.put(1.0f, NEW_FRACTION_COLOR);
                }
            }
            else if(TMP_FRACTION >= 1)
            {
                FRACTION_COLORS.put(TMP_FRACTION - 1.0f - 0.0001f, TMP_COLOR);

                final float PREVIOUS_FRACTION;
                final java.awt.Color PREVIOUS_COLOR;
                if (i > 0)
                {
                    PREVIOUS_FRACTION = FRACTION_LIST.get(i - 1) + OFFSET;
                    PREVIOUS_COLOR = COLOR_LIST.get(i - 1);
                }
                else
                {
                    PREVIOUS_FRACTION = FRACTION_LIST.get(MAX_FRACTIONS - 1) + OFFSET;
                    PREVIOUS_COLOR = COLOR_LIST.get(MAX_FRACTIONS - 1);
                }
                if (PREVIOUS_FRACTION < 1)
                {
                    final java.awt.Color NEW_FRACTION_COLOR = getColorFromFraction(TMP_COLOR, PREVIOUS_COLOR, (int) ((TMP_FRACTION - PREVIOUS_FRACTION) * 10000), (int) (TMP_FRACTION - 1.0f) * 10000);
                    FRACTION_COLORS.put(1.0f, NEW_FRACTION_COLOR);
                    FRACTION_COLORS.put(0.0f, NEW_FRACTION_COLOR);
                }
            }
            else
            {
                FRACTION_COLORS.put(TMP_FRACTION, TMP_COLOR);
            }
        }

        // Clear the original FRACTION_LIST and COLOR_LIST
        FRACTION_LIST.clear();
        COLOR_LIST.clear();

        return FRACTION_COLORS;
    }

    /**
     * With the START_COLOR at the beginning and the DESTINATION_COLOR at the end of the given RANGE the method will calculate
     * and return the color that equals the given VALUE.
     * e.g. a START_COLOR of BLACK (R:0, G:0, B:0, A:255) and a DESTINATION_COLOR of WHITE(R:255, G:255, B:255, A:255)
     * with a given RANGE of 100 and a given VALUE of 50 will return the color that is exactly in the middle of the
     * gradient between black and white which is gray(R:128, G:128, B:128, A:255)
     * So this method is really useful to calculate colors in gradients between two given colors.
     * @param START_COLOR
     * @param DESTINATION_COLOR
     * @param RANGE
     * @param VALUE
     * @return Color calculated from a range of values by given value
     */
    public java.awt.Color getColorFromFraction(final java.awt.Color START_COLOR, final java.awt.Color DESTINATION_COLOR, final int RANGE, final int VALUE)
    {
        final float SOURCE_RED = START_COLOR.getRed() * INT_TO_FLOAT_CONST;
        final float SOURCE_GREEN = START_COLOR.getGreen() * INT_TO_FLOAT_CONST;
        final float SOURCE_BLUE = START_COLOR.getBlue() * INT_TO_FLOAT_CONST;
        final float SOURCE_ALPHA = START_COLOR.getAlpha() * INT_TO_FLOAT_CONST;

        final float DESTINATION_RED = DESTINATION_COLOR.getRed() * INT_TO_FLOAT_CONST;
        final float DESTINATION_GREEN = DESTINATION_COLOR.getGreen() * INT_TO_FLOAT_CONST;
        final float DESTINATION_BLUE = DESTINATION_COLOR.getBlue() * INT_TO_FLOAT_CONST;
        final float DESTINATION_ALPHA = DESTINATION_COLOR.getAlpha() * INT_TO_FLOAT_CONST;

        final float RED_DELTA = DESTINATION_RED - SOURCE_RED;
        final float GREEN_DELTA = DESTINATION_GREEN - SOURCE_GREEN;
        final float BLUE_DELTA = DESTINATION_BLUE - SOURCE_BLUE;
        final float ALPHA_DELTA = DESTINATION_ALPHA - SOURCE_ALPHA;

        final float RED_FRACTION = RED_DELTA / RANGE;
        final float GREEN_FRACTION = GREEN_DELTA / RANGE;
        final float BLUE_FRACTION = BLUE_DELTA / RANGE;
        final float ALPHA_FRACTION = ALPHA_DELTA / RANGE;
        //System.out.println(DISTANCE + "     " + CURRENT_FRACTION);

        return new java.awt.Color(SOURCE_RED + RED_FRACTION * VALUE, SOURCE_GREEN + GREEN_FRACTION * VALUE, SOURCE_BLUE + BLUE_FRACTION * VALUE, SOURCE_ALPHA + ALPHA_FRACTION * VALUE);
    }

    @Override
    public java.awt.PaintContext createContext(final java.awt.image.ColorModel COLOR_MODEL, final java.awt.Rectangle DEVICE_BOUNDS, final java.awt.geom.Rectangle2D USER_BOUNDS, final java.awt.geom.AffineTransform TRANSFORM, final java.awt.RenderingHints HINTS)
    {
        final java.awt.geom.Point2D TRANSFORMED_CENTER = TRANSFORM.transform(CENTER, null);
        return new ConicalGradientPaintContext(TRANSFORMED_CENTER);
    }

    @Override
    public int getTransparency()
    {
        return java.awt.Transparency.TRANSLUCENT;
    }

    private final class ConicalGradientPaintContext implements java.awt.PaintContext
    {
        final private java.awt.geom.Point2D CENTER;

        public ConicalGradientPaintContext(final java.awt.geom.Point2D CENTER)
        {
            this.CENTER = new java.awt.geom.Point2D.Double(CENTER.getX(), CENTER.getY());
        }

        @Override
        public void dispose()
        {
        }

        @Override
        public java.awt.image.ColorModel getColorModel()
        {
            return java.awt.image.ColorModel.getRGBdefault();
        }

        @Override
        public java.awt.image.Raster getRaster(final int X, final int Y, final int TILE_WIDTH, final int TILE_HEIGHT)
        {
            final double ROTATION_CENTER_X = -X + CENTER.getX();
            final double ROTATION_CENTER_Y = -Y + CENTER.getY();

            final int MAX = FRACTION_ANGLES.length;

            // Create raster for given colormodel
            final java.awt.image.WritableRaster RASTER = getColorModel().createCompatibleWritableRaster(TILE_WIDTH, TILE_HEIGHT);

            // Create data array with place for red, green, blue and alpha values
            int[] data = new int[(TILE_WIDTH * TILE_HEIGHT * 4)];

            double dx;
            double dy;
            double distance;
            double angle;
            double currentRed = 0;
            double currentGreen = 0;
            double currentBlue = 0 ;
            double currentAlpha = 0;

            for (int py = 0; py < TILE_HEIGHT; py++)
            {
                for (int px = 0; px < TILE_WIDTH; px++)
                {

                    // Calculate the distance between the current position and the rotation angle
                    dx = px - ROTATION_CENTER_X;
                    dy = py - ROTATION_CENTER_Y;
                    distance = Math.sqrt(dx * dx + dy * dy);

                    // Avoid division by zero
                    if (distance == 0)
                    {
                        distance = 1;
                    }

                    // 0 degree on top
                    angle = Math.abs(Math.toDegrees(Math.acos(dx / distance)));

                    if (dx >= 0 && dy <= 0)
                    {
                        angle = 90.0 - angle;
                    }
                    else if (dx >= 0 && dy >= 0)
                    {
                        angle += 90.0;
                    }
                    else if (dx <= 0 && dy >= 0)
                    {
                        angle += 90.0;
                    }
                    else if (dx <= 0 && dy <= 0)
                    {
                        angle = 450.0 - angle;
                    }

                    // Check for each angle in fractionAngles array
                    for (int i = 0 ; i < (MAX - 1) ; i++)
                    {
                        if ((angle >= FRACTION_ANGLES[i]) )
                        {
                            currentRed = COLORS[i].getRed() * INT_TO_FLOAT_CONST + (angle - FRACTION_ANGLES[i]) * RED_STEP_LOOKUP[i];
                            currentGreen = COLORS[i].getGreen() * INT_TO_FLOAT_CONST + (angle - FRACTION_ANGLES[i]) * GREEN_STEP_LOOKUP[i];
                            currentBlue = COLORS[i].getBlue() * INT_TO_FLOAT_CONST + (angle - FRACTION_ANGLES[i]) * BLUE_STEP_LOOKUP[i];
                            currentAlpha = COLORS[i].getAlpha() * INT_TO_FLOAT_CONST + (angle - FRACTION_ANGLES[i]) * ALPHA_STEP_LOOKUP[i];
                            continue;
                        }
                    }

                    // Fill data array with calculated color values
                    final int BASE = (py * TILE_WIDTH + px) * 4;
                    data[BASE + 0] = (int) (currentRed * 255);
                    data[BASE + 1] = (int) (currentGreen * 255);
                    data[BASE + 2] = (int) (currentBlue * 255);
                    data[BASE + 3] = (int) (currentAlpha * 255);
                }
            }

            // Fill the raster with the data
            RASTER.setPixels(0, 0, TILE_WIDTH, TILE_HEIGHT, data);

            return RASTER;
        }
    }
}




© 2015 - 2024 Weber Informatics LLC | Privacy Policy