Java Code Examples for com.google.gwt.canvas.client.Canvas#getContext2d()

Canvas createImageCanvas(int [] pixels, int width, int height) {

	    Canvas canvas = Canvas.createIfSupported();
	    canvas.setCoordinateSpaceWidth(width);
	    canvas.setCoordinateSpaceHeight(height);

	    Context2d context = canvas.getContext2d();
	    ImageData data = context.createImageData(width, height);

	    CanvasPixelArray array = data.getData();
	    for(int i=0; i<width*height; i++) {
	        array.set(4*i+0, pixels[i] & 0xFF);
	        array.set(4*i+1, (pixels[i] >> 8) & 0xFF);
	        array.set(4*i+2, (pixels[i] >> 16) & 0xFF);
	        array.set(4*i+3, (pixels[i] >> 24) & 0xFF);
	    }
	    context.putImageData(data, 0, 0);

	    return canvas;

	}
 

private Canvas createImageCanvas(int [] pixels, int width, int height) {
	
	Canvas canvas = Canvas.createIfSupported();
	canvas.setCoordinateSpaceWidth(width);
	canvas.setCoordinateSpaceHeight(height);
	
	Context2d context = canvas.getContext2d();
	ImageData data = context.createImageData(width, height);

	CanvasPixelArray array = data.getData();
	for(int i=0; i<width*height; i++) { // ABGR
		array.set(4*i+0, pixels[i] & 0xFF);
		array.set(4*i+1, (pixels[i] >> 8) & 0xFF);
		array.set(4*i+2, (pixels[i] >> 16) & 0xFF);
		array.set(4*i+3, (pixels[i] >> 24) & 0xFF);
	}
	context.putImageData(data, 0, 0);
	
	canvas.getElement().getStyle().setMargin(4, Unit.PX);
	
	return canvas;
	
}
 

private static void draw(CanvasElement el, String idcode, String coordinates) {
    Canvas canvas = Canvas.wrap(el);
    if (idcode != null && idcode.length() > 0) {
        String combined = idcode + (coordinates != null ? " " + coordinates : "");
        Context2d ctx = canvas.getContext2d();
        drawMolecule(ctx, combined, canvas.getCoordinateSpaceWidth(), canvas.getCoordinateSpaceHeight());
    }
}
 

public static void drawIDCode(CanvasElement el, String idcode, String coordinates, int displayMode,
        String[] atomText) {
    Canvas canvas = Canvas.wrap(el);
    if (idcode != null && idcode.length() > 0) {
        String combined = idcode + (coordinates != null ? " " + coordinates : "");
        Context2d ctx = canvas.getContext2d();
        drawMolecule(ctx, combined, canvas.getCoordinateSpaceWidth(), canvas.getCoordinateSpaceHeight(),
                displayMode, atomText);
    }
}
 

private void draw(Canvas canvas) {
  long fg = builder.getForegroundColor();
  Context2d context2d = canvas.getContext2d();
  int w = (int) model.getDisplaySize().getWidth();
  int h = (int) model.getDisplaySize().getHeight();

  int displayMode = model.getDisplayMode();

  drawBackground(context2d, w, h);

  if (isReaction()) {
    model.analyzeFragmentMembership();
    if (model.needsLayout())
      model.cleanReaction(true);
  }

  AbstractExtendedDepictor depictor = createDepictor();
  depictor.setDisplayMode(displayMode);

  if (model.needsLayout()) {
    depictor.updateCoords(null, new java.awt.geom.Rectangle2D.Double(0, 0, (float) w, (float) h),
        AbstractDepictor.cModeInflateToMaxAVBL);
  }
  model.needsLayout(false);

  depictor.paint(context2d);
  // Let the actions draw if needed e.g. NewChainAction
  if (action != null) {
    GraphicsContext ctx = new GraphicsContext(context2d);
    ctx.save();
    ctx.setStroke(fg);
    ctx.setFill(fg);
    action.paint(ctx);
    ctx.restore();
  }
}
 

public static void scaleCanvas(Canvas canvas, int width, int height) {
  canvas.setWidth(width + "px");
  canvas.setHeight(height + "px");

  Context2d ctx = canvas.getContext2d();

  double ratio = Util.getDevicePixelRatio();
  canvas.setCoordinateSpaceWidth((int)(width * ratio));
  canvas.setCoordinateSpaceHeight((int)(height * ratio));
  ctx.scale(ratio, ratio);
}
 

/**
 * Drawing function
 *
 * @param canvas
 */
private void draw(Canvas canvas) {
  Context2d context2d = canvas.getContext2d();
  GraphicsContext ctx = new GraphicsContext(context2d);
  drawButtons(ctx);
  drawESRButtons(ctx);
  drawHover(ctx);
}
 

private static int measureHeight(Font font, String text) {
  Canvas canvas = canvas();
  Context2d ctx = canvas.getContext2d();

  ctx.setFont(getFontString(font));
  ctx.setFillStyle("rgb(255, 0, 0)");

  int width = (int) ctx.measureText(text).getWidth();
  int canvasHeight = font.getSize() * 2;
  canvas.setHeight(canvasHeight + "px");
  canvas.setHeight(font.getSize() * 2 + "px");
  canvas.setWidth(width + "px");

  ctx.fillText(text, 0, font.getSize());
  ImageData data = ctx.getImageData(0, 0, width, canvasHeight);
  int firstY = canvasHeight - 1;
  int lastY = 0;
  for (int x = 0; x < width; x++) {
    for (int y = 0; y < canvasHeight; y++) {
      int red = data.getRedAt(x, y);
      if (red != 0) {
        if (firstY > y) {
          firstY = y;
        }
        if (lastY < y) {
          lastY = y;
        }
      }
    }
  }
  return lastY - firstY;
}
 

public Canvas getCircuitAsCanvas(boolean print) {
    	// create canvas to draw circuit into
    	Canvas cv = Canvas.createIfSupported();
    	Rectangle bounds = getCircuitBounds();
    	
	// add some space on edges because bounds calculation is not perfect
    	int wmargin = 140;
    	int hmargin = 100;
    	int w = (bounds.width+wmargin) ;
    	int h = (bounds.height+hmargin) ;
    	cv.setCoordinateSpaceWidth(w);
    	cv.setCoordinateSpaceHeight(h);
    	double oldTransform[] = Arrays.copyOf(transform, 6);
    
	Context2d context = cv.getContext2d();
	Graphics g = new Graphics(context);
	context.setTransform(1, 0, 0, 1, 0, 0);
        
        double scale = 1;
        
	// turn on white background, turn off current display
	boolean p = printableCheckItem.getState();
	boolean c = dotsCheckItem.getState();
	if (print)
	    printableCheckItem.setState(true);
        if (printableCheckItem.getState()) {
            CircuitElm.whiteColor = Color.black;
            CircuitElm.lightGrayColor = Color.black;
            g.setColor(Color.white);
        } else {
            CircuitElm.whiteColor = Color.white;
            CircuitElm.lightGrayColor = Color.lightGray;
            g.setColor(Color.black);
            g.fillRect(0, 0, g.context.getCanvas().getWidth(), g.context.getCanvas().getHeight());
        }
	dotsCheckItem.setState(false);

        if (bounds != null)
            scale = Math.min(w /(double)(bounds.width+wmargin),
                             h/(double)(bounds.height+hmargin));
        scale = Math.min(scale, 1.5); // Limit scale so we don't create enormous circuits in big windows
        
        // ScopeElms need the transform array to be updated
	transform[0] = transform[3] = scale;
	transform[4] = -(bounds.x-wmargin/2);
	transform[5] = -(bounds.y-hmargin/2);
	context.scale(scale, scale);
	context.translate(transform[4], transform[5]);
	
	// draw elements
	int i;
	for (i = 0; i != elmList.size(); i++) {
	    getElm(i).draw(g);
	}
	
	// restore everything
	printableCheckItem.setState(p);
	dotsCheckItem.setState(c);
	transform = oldTransform;
	return cv;
}
 

public static void drawMolecule(CanvasElement el, JSMolecule mol, int displayMode, String[] atomText) {
    Canvas canvas = Canvas.wrap(el);
    Context2d ctx = canvas.getContext2d();
    drawMolecule(ctx, mol.getStereoMolecule(), canvas.getCoordinateSpaceWidth(), canvas.getCoordinateSpaceHeight(),
            displayMode, atomText);
}
 

private void draw(Canvas toolBar) {
  Context2d context2d = toolBar.getContext2d();
  drawButtons(new GraphicsContext(context2d));
}
 

private void draw(Canvas toolBar) {
  Context2d context2d = toolBar.getContext2d();
  GraphicsContext ctx = new GraphicsContext(context2d);
  drawButtons(ctx);
  drawESRButtons(ctx);
}
 

static double calculateWidth(Font font, String text) {
  Canvas canvas = canvas();
  Context2d ctx = canvas.getContext2d();
  ctx.setFont(getFontString(font));
  return ctx.measureText(normalize(text)).getWidth();
}