Example usage for com.google.gwt.canvas.dom.client Context2d setGlobalAlpha

List of usage examples for com.google.gwt.canvas.dom.client Context2d setGlobalAlpha

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Introduction

In this page you can find the example usage for com.google.gwt.canvas.dom.client Context2d setGlobalAlpha.

Prototype

public final native void setGlobalAlpha(double alpha) ;

Source Link

Document

Sets the global alpha value.

Usage

From source file:com.sencha.gxt.chart.client.draw.engine.Canvas2d.java

License:sencha.com license

/**
 * In the Canvas2d class, this method does more or less what renderSprite does in SVG and VML - it
 * actually renders the sprite to the dom.
 * @param sprite the sprite to draw/*from ww w . ja  v  a2 s  .  c  o  m*/
 */
protected void append(Sprite sprite) {
    if (sprite.isHidden() || sprite.getOpacity() == 0) {
        return;
    }
    Context2d ctx = getContext();
    ctx.save();
    //set global stuff, fill, stroke, clip, etc

    //clip - deal with translation or normal rectangle
    if (sprite.getClipRectangle() != null) {
        PreciseRectangle clip = sprite.getClipRectangle();
        if (sprite.getScaling() != null || sprite.getTranslation() != null || sprite.getRotation() != null) {
            PathSprite transPath = new PathSprite(new RectangleSprite(clip));
            transPath = transPath.map(sprite.transformMatrix());
            appendPath(ctx, transPath);
        } else {
            ctx.beginPath();
            ctx.rect(clip.getX(), clip.getY(), clip.getWidth(), clip.getHeight());
            ctx.closePath();
        }
        ctx.clip();
    }

    if (sprite.getScaling() != null || sprite.getTranslation() != null || sprite.getRotation() != null
            || (component.isViewBox() && viewbox != null)) {
        Matrix matrix = sprite.transformMatrix();
        if (matrix != null) {
            //TODO consider replacing this transform call with three distinct calls to translate/scale/rotate if cheaper
            ctx.transform(matrix.get(0, 0), matrix.get(1, 0), matrix.get(0, 1), matrix.get(1, 1),
                    matrix.get(0, 2), matrix.get(1, 2));
        }
        if (component.isViewBox() && viewbox != null) {
            double size = Math.min(getWidth() / viewbox.getWidth(), getHeight() / viewbox.getHeight());

            ctx.scale(size, size);
            ctx.translate(-viewbox.getX(), -viewbox.getY());
        }
    }

    //TODO see about caching colors via the dirty flag? If we don't use a color/gradient for a pass or three, dump it
    double opacity = Double.isNaN(sprite.getOpacity()) ? 1.0 : sprite.getOpacity();
    PreciseRectangle untransformedBbox = sprite.getPathSprite().dimensions();
    if (sprite.getStroke() != null && sprite.getStroke() != Color.NONE && sprite.getStrokeWidth() != 0) {
        ctx.setLineWidth(Double.isNaN(sprite.getStrokeWidth()) ? 1.0 : sprite.getStrokeWidth());
        ctx.setStrokeStyle(getColor(sprite.getStroke(), untransformedBbox));//TODO read bbox from cache
    }
    if (sprite.getFill() != null && sprite.getFill() != Color.NONE) {
        ctx.setFillStyle(getColor(sprite.getFill(), untransformedBbox));//TODO read bbox from cache
    }

    if (sprite instanceof PathSprite) {
        appendPath(ctx, (PathSprite) sprite);
    } else if (sprite instanceof TextSprite) {
        TextSprite text = (TextSprite) sprite;
        //TODO style and weight
        ctx.setFont(text.getFontSize() + "px " + text.getFont());
        ctx.setTextAlign(getTextAlign(text.getTextAnchor()));
        ctx.setTextBaseline(getTextBaseline(text.getTextBaseline()));
        ctx.fillText(text.getText(), text.getX(), text.getY());
    } else if (sprite instanceof RectangleSprite) {
        RectangleSprite rect = (RectangleSprite) sprite;
        if (Double.isNaN(rect.getRadius()) || rect.getRadius() == 0) {
            if (sprite.getFill() != null && sprite.getFill() != Color.NONE) {
                ctx.setGlobalAlpha(
                        Double.isNaN(sprite.getFillOpacity()) ? opacity : opacity * sprite.getFillOpacity());
                ctx.fillRect(rect.getX(), rect.getY(), rect.getWidth(), rect.getHeight());
            }
            if (sprite.getStroke() != null && sprite.getStroke() != Color.NONE
                    && sprite.getStrokeWidth() != 0) {
                ctx.setGlobalAlpha(Double.isNaN(sprite.getStrokeOpacity()) ? opacity
                        : opacity * sprite.getStrokeOpacity());
                ctx.strokeRect(rect.getX(), rect.getY(), rect.getWidth(), rect.getHeight());
            }
        } else {
            appendPath(ctx, rect.getPathSprite());
        }
    } else if (sprite instanceof CircleSprite) {
        CircleSprite circle = (CircleSprite) sprite;
        ctx.beginPath();
        ctx.arc(circle.getCenterX(), circle.getCenterY(), circle.getRadius(), 0, 2 * Math.PI);
        ctx.closePath();
        if (sprite.getFill() != null && sprite.getFill() != Color.NONE) {
            ctx.setGlobalAlpha(
                    Double.isNaN(sprite.getFillOpacity()) ? opacity : opacity * sprite.getFillOpacity());
            ctx.fill();
        }
        if (sprite.getStroke() != null && sprite.getStroke() != Color.NONE && sprite.getStrokeWidth() != 0) {
            ctx.setGlobalAlpha(
                    Double.isNaN(sprite.getStrokeOpacity()) ? opacity : opacity * sprite.getStrokeOpacity());
            ctx.stroke();
        }
    } else if (sprite instanceof EllipseSprite) {
        appendPath(ctx, sprite.getPathSprite());
    } else if (sprite instanceof ImageSprite) {
        ImageSprite image = (ImageSprite) sprite;
        ImageElement elt = Document.get().createImageElement();
        elt.setSrc(image.getResource().getSafeUri().asString());
        ctx.drawImage(elt, image.getX(), image.getY(), image.getWidth(), image.getHeight());
    }

    ctx.restore();

    if (!REDRAW_ALL) {
        renderedBbox.put(sprite, getBBox(sprite));
    }

    sprite.clearDirtyFlags();
}

From source file:com.sencha.gxt.chart.client.draw.engine.Canvas2d.java

License:sencha.com license

protected void appendPath(Context2d ctx, PathSprite sprite) {
    ctx.beginPath();//from w  w  w  .  ja v a  2 s .  c o m
    sprite.toAbsolute();
    //    sprite = sprite.copy().toCurve();

    PrecisePoint currentPoint = new PrecisePoint();
    PrecisePoint movePoint = new PrecisePoint();
    PrecisePoint curvePoint = new PrecisePoint();
    PrecisePoint quadraticPoint = new PrecisePoint();

    appendPathCommands(ctx, sprite.getCommands(), currentPoint, movePoint, curvePoint, quadraticPoint);

    double opacity = Double.isNaN(sprite.getOpacity()) ? 1.0 : sprite.getOpacity();
    if (sprite.getFill() != null && sprite.getFill() != Color.NONE) {
        ctx.setGlobalAlpha(Double.isNaN(sprite.getFillOpacity()) ? opacity : opacity * sprite.getFillOpacity());
        ctx.fill();
    }
    if (sprite.getStroke() != null && sprite.getStroke() != Color.NONE && sprite.getStrokeWidth() != 0) {
        ctx.setLineCap(sprite.getStrokeLineCap() == null ? LineCap.BUTT : sprite.getStrokeLineCap());
        ctx.setLineJoin(sprite.getStrokeLineJoin() == null ? LineJoin.MITER : sprite.getStrokeLineJoin());
        ctx.setMiterLimit(sprite.getMiterLimit() == Double.NaN ? 4 : sprite.getMiterLimit());
        ctx.setGlobalAlpha(
                Double.isNaN(sprite.getStrokeOpacity()) ? opacity : opacity * sprite.getStrokeOpacity());
        ctx.stroke();
    }
}

From source file:de.ga_ap.cirrus.newcloud.client.TheCloud.java

License:Open Source License

public TheCloud(final Element cloudContainer) {

    final NodeList<Element> aElements = cloudContainer.getElementsByTagName("A");
    final int height = cloudContainer.getOffsetHeight();
    final int width = cloudContainer.getOffsetWidth();

    final Canvas canvas = Canvas.createIfSupported();
    canvas.setCoordinateSpaceHeight(height);
    canvas.setCoordinateSpaceWidth(width);
    final Context2d context2d = canvas.getContext2d();

    final double radius = canvas.getCanvasElement().getHeight() / 3;
    final int refreshrate = 30;

    final List<CloudItem> itemList = new ArrayList<CloudItem>(aElements.getLength());
    for (int i = 0; i < aElements.getLength(); i++) {
        final Element el = aElements.getItem(i);
        final CloudItem ci = new CloudItem();
        ci.text = el.getInnerText();/* ww  w .j  av  a 2 s  . co m*/
        itemList.add(ci);
    }
    cloudContainer.setInnerText("");

    final int itemListSize = itemList.size();
    for (int i = 1; i <= itemListSize; i++) {
        final CloudItem ci = itemList.get(i - 1);
        ci.theta = Math.acos(-1.0 + (2.0 * (double) i - 1.0) / itemListSize);
        ci.phi = Math.sqrt(itemListSize * Math.PI) * ci.theta;

        ci.z = radius * Math.cos(ci.theta);
        ci.y = radius * Math.sin(ci.theta) * Math.cos(ci.phi);
        ci.x = radius * Math.sin(ci.theta) * Math.sin(ci.phi);

        // TODO heightOfAllItems ?!

        // TODO font size

        context2d.fillText(ci.text, ci.y, ci.z);
        System.out.println(ci.x + " " + ci.y + " " + ci.z + " - " + ci.theta + " " + ci.phi);

    }

    Scheduler.get().scheduleFixedPeriod(new RepeatingCommand() {

        @Override
        public boolean execute() {

            canvas.setCoordinateSpaceHeight(height);
            canvas.setCoordinateSpaceWidth(width);

            final double cosPsi = Math.cos(psi);
            final double sinPsi = Math.sin(psi);

            final double cosTheta = Math.cos(theta);
            final double sinTheta = Math.sin(theta);

            final double sinThetaCosPsi = sinTheta * cosPsi;
            final double sinThetaSinPsi = sinTheta * sinPsi;

            for (final CloudItem ci : itemList) {

                final double x, y, z;

                x = ci.x * cosTheta * cosPsi + ci.y * cosTheta * sinPsi - ci.z * sinTheta;
                y = ci.x * (-sinPsi) + ci.y * cosPsi;
                z = ci.x * sinThetaCosPsi + ci.y * sinThetaSinPsi + ci.z * cosTheta;
                ci.x = x;
                ci.y = y;
                ci.z = z;

                context2d.setGlobalAlpha(0.7 + ci.x / radius / 3.0);
                context2d.setFont("20pt Arial");
                context2d.fillText(ci.text, radius + ci.y, radius + ci.z);

                // System.out.println(ci.x + " " + ci.y + " " + ci.z + " - "
                // + ci.theta + " " + ci.phi + " " + ci.text);
            }

            theta += ySteps;
            psi += xSteps;
            // System.out.println(theta);
            if (theta > Math.PI * 2.0) {
                theta = 0.0;
            }
            if (psi > Math.PI * 2.0) {
                psi = 0.0;
            }
            return true;
        }
    }, refreshrate);

    // final EventListener listener = new EventListener() {
    //
    // @Override
    // public void onBrowserEvent(final Event event) {
    // if (event.getTypeInt() == Event.ONMOUSEMOVE) {
    // moveSteps(event);
    // } else if (event.getTypeInt() == Event.ONTOUCHMOVE) {
    // event.preventDefault(); // prevents the default behavior of
    // // a page when touching
    // moveSteps(event);
    // }
    // }
    //
    // private void moveSteps(final Event event) {
    // ySteps = -((event.getClientY() + Window.getScrollTop())
    // / canvas.getCoordinateSpaceHeight() * 0.000002 - 0.1) / 2.0;
    // xSteps = ((event.getClientX() + Window.getScrollLeft())
    // / canvas.getCoordinateSpaceWidth() * 0.000002 - 0.1) / 2.0;
    // }
    // };
    //
    // DOM.setEventListener(
    // (com.google.gwt.user.client.Element) cloudContainer, listener);
    // DOM.sinkEvents((com.google.gwt.user.client.Element) cloudContainer,
    // Event.ONMOUSEMOVE + Event.ONTOUCHMOVE);

    System.out.println(radius);
    cloudContainer.appendChild(canvas.getCanvasElement());
}

From source file:examples.geometry.demos.RegionClippingExample.java

License:Open Source License

@Override
protected ControllableShape[] createShapes(Canvas canvas, EventBus eventBus) {
    return new ControllableShape[] { new ControllableShape(canvas, eventBus) {
        {//from  ww  w  .j av a2  s.c om
            addControlPoints(new Point(100, 100), new Point(200, 200));
            addControlPoints(new Point(150, 150), new Point(250, 250));
        }

        @Override
        public Region getShape() {
            Point[] cp = getPoints();
            Region region = new Region(new Rectangle(cp[0], cp[1]), new Rectangle(cp[2], cp[3]));
            return region;
        }

        @Override
        public void onDraw(Canvas canvas) {
            Context2d context = canvas.getContext2d();
            Region region = getShape();

            context.save();
            context.beginPath();
            Rectangle rr = region.getBounds();
            context.rect(rr.getX(), rr.getY(), rr.getWidth(), rr.getHeight());
            //            context.fill();
            context.clip();

            for (int y = 0; y < 800; y += 20) {
                context.fillText(
                        "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz",
                        20, y);
            }

            context.restore();

            context.setFillStyle("blue");
            context.setGlobalAlpha(0.5);
            context.beginPath();
            for (Rectangle r : region.getShapes()) {
                context.fillRect(r.getX(), r.getY(), r.getWidth(), r.getHeight());
            }
            context.closePath();
            context.setFillStyle("black");
            context.setGlobalAlpha(1);
        }
    } };
}

From source file:examples.geometry.demos.RegionOutlineExample.java

License:Open Source License

@Override
protected ControllableShape[] createShapes(Canvas canvas, EventBus eventBus) {
    return new ControllableShape[] { new ControllableShape(canvas, eventBus) {
        {//from   w  w w .j  a v  a 2 s . com
            addControlPoints(new Point(100, 50), new Point(300, 100));
            addControlPoints(new Point(250, 200), new Point(350, 330));
            addControlPoints(new Point(100, 200), new Point(190, 325));
            addControlPoints(new Point(150, 300), new Point(280, 380));
        }

        @Override
        public Region getShape() {
            Point[] cp = getPoints();

            Rectangle[] rectangles = new Rectangle[cp.length / 2];
            for (int i = 0; i < rectangles.length; i++) {
                rectangles[i] = new Rectangle(cp[2 * i], cp[2 * i + 1]);
            }

            return new Region(rectangles);
        }

        @Override
        public void onDraw(Canvas canvas) {
            Context2d context = canvas.getContext2d();
            Region region = getShape();

            context.setFillStyle("rgba(0, 0, 255, 0.5)");
            context.setGlobalAlpha(0.5);

            context.beginPath();
            for (Rectangle r : region.getShapes()) {
                context.fillRect(r.getX(), r.getY(), r.getWidth(), r.getHeight());
            }
            context.closePath();

            //            gc.setAlpha(255);
            context.setFillStyle("rgba(255, 255, 255, 1)");
            context.setGlobalAlpha(1);
            // gc.setForeground(Display.getCurrent().getSystemColor(
            // SWT.COLOR_RED));
            // for (Rectangle r : region.getShapes()) {
            // gc.drawRectangle(r.toSWTRectangle());
            // }
            //            gc.setForeground(Display.getCurrent().getSystemColor(SWT.COLOR_BLACK));
            context.beginPath();
            for (Line l : region.getOutlineSegments()) {
                Point p1 = l.getP1();
                Point p2 = l.getP2();
                context.moveTo(p1.x, p1.y);
                context.lineTo(p2.x, p2.y);
                context.stroke();
            }
            context.closePath();
        }
    } };
}

From source file:org.catrobat.html5player.client.Scene.java

License:Open Source License

/**
 *
 * @param imageElement/*  w  w w  . j  a  v a 2 s.  com*/
 * @param x
 * @param y
 * @param width
 * @param height
 */
public void drawImageElement(ImageElement imageElement, double x, double y, double width, double height,
        double alpha) {

    long start = System.currentTimeMillis();

    Context2d context = sceneCanvas.getContext2d();
    context.save();
    context.setGlobalAlpha(alpha);
    context.drawImage(imageElement, x, y, width, height);
    context.restore();

    CatrobatDebug.debug("drawImageElement-execution took " + (System.currentTimeMillis() - start) + " ms");
}

From source file:org.catrobat.html5player.client.Scene.java

License:Open Source License

/**
 *
 * @param imageElement/* w w w .ja v a  2s  . c  o  m*/
 * @param translateX
 * @param translateY
 * @param x
 * @param y
 * @param width
 * @param height
 * @param degrees
 * @param xSize
 * @param ySize
 */
public void drawImageElement(ImageElement imageElement, double translateX, double translateY, double x,
        double y, double width, double height, double degrees, double xSize, double ySize, double alpha) {

    long start = System.currentTimeMillis();

    Context2d context = sceneCanvas.getContext2d();

    context.save();
    context.setGlobalAlpha(alpha);
    context.translate(translateX, translateY);
    context.rotate(Math.toRadians(degrees));
    context.scale(xSize, ySize);
    context.drawImage(imageElement, x, y, width, height);

    //for testing - draws a rectangular around the sprite
    //      context.strokeRect(x, y, width, height);
    //

    context.restore();

    CatrobatDebug.debug("drawImageElement-execution took " + (System.currentTimeMillis() - start) + " ms");
}

From source file:org.catrobat.html5player.client.Scene.java

License:Open Source License

/**
 *
 * @param imageElement//from ww  w  .  j a va  2  s . com
 * @param translateX
 * @param translateY
 * @param x
 * @param y
 * @param width
 * @param height
 * @param degrees
 * @param xSize
 * @param ySize
 */
public void drawImageElementBrightness(ImageElement imageElement, double translateX, double translateY,
        double x, double y, double width, double height, double degrees, double alpha, double brightness)
        throws JavaScriptException {
    Context2d context = sceneCanvas.getContext2d();
    context.save();
    context.setGlobalAlpha(alpha);
    context.translate(translateX, translateY);
    context.rotate(degrees * Math.PI / 180);

    try {
        Canvas adjustedImage = adjustImageBrightness(imageElement, brightness);
        context.drawImage(adjustedImage.getCanvasElement(), x, y, width, height);
        context.restore();
    } catch (JavaScriptException exception) {
        context.restore();
        throw exception;
    }
}

From source file:playn.html.HtmlCanvasLayerCanvas.java

License:Apache License

@Override
void paint(Context2d ctx, float parentAlpha) {
    ctx.save();/*from w  w w.j a va  2s  . c om*/
    transform(ctx);

    ctx.setGlobalAlpha(parentAlpha * alpha);
    ctx.drawImage(canvas.canvas(), 0, 0);

    ctx.restore();
}

From source file:playn.html.HtmlImageLayerCanvas.java

License:Apache License

@Override
public void paint(Context2d ctx, float parentAlpha) {
    if (!visible() || !img.isReady())
        return;//from   w  w  w . j  a  va  2 s  .  co m

    ctx.save();
    transform(ctx);
    ctx.setGlobalAlpha(parentAlpha * alpha);

    float width = width();
    float height = height();
    if (repeatX || repeatY) {
        updatePattern(ctx);
        ctx.setFillStyle(pattern);
        ctx.beginPath();
        ctx.rect(0, 0, width, height);
        ctx.scale(repeatX ? 1 : width / img.width(), repeatY ? 1 : height / img.height());
        ctx.fill();
    } else {
        ((HtmlCanvas.Drawable) img).draw(ctx, 0, 0, width, height);
    }

    ctx.restore();
}