Develop Reference

How to fill path with only effect without color inside it or low opacity color in JavaFx?

I'm currently using Canvas in JavaFx8.
Let's say I just draw some path inside GraphicContex, and fill it with green ,stroke it with yellow while apply yellow inner shadow effect on it. Here is my current code
public void draw(GraphicsContext gc) {
drawsomePath(gc);
gc.setFill(Color.rgb(0, 255, 0, 1d));
InnerShadow innerglow = new InnerShadow(20.0d, Color.rgb(255, 255, 0, 1.0d));
innerglow.setChoke(0.5);
gc.setEffect(innerglow);
gc.fill();
gc.setStroke(Color.rgb(255, 255, 0, 1.0d));
gc.setLineWidth(3);
gc.stroke();
gc.setLineWidth(1);
gc.setEffect(null);
}
With this code I'm able to achieve this:
which is not what I want, here is what I want:
As you can see what I want is to have path filled with color that are semi-transparent green or transparent.
I've try adjust the alpha value or fill Color.TRANSPARENT with effect apply... These doesn't work. It looks like JavaFx effect care about alpha value of filled color.
How do I get this to work?
Ps. photos are photoshoped to make it easy to understand.

Libgdx slider - drawables are drawn the wrong size

I am drawing a slider with Libgdx using the following code:
Pixmap pix = new Pixmap(200, 50, Pixmap.Format.RGBA8888);
pix.setColor(Color.BLACK);
pix.fill();
skin.add("sliderBackS", new Texture(pix));
Pixmap pix1 = new Pixmap(10, 70, Pixmap.Format.RGBA8888);
pix1.setColor(Color.RED);
pix1.fill();
skin.add("knobS", new Texture(pix1));
Slider.SliderStyle sliderStyle = new Slider.SliderStyle();
sliderStyle.disabledBackground = skin.newDrawable("sliderBackS");
sliderStyle.disabledKnob = skin.newDrawable("knobS");
sliderStyle.background = skin.newDrawable("sliderBackS");
sliderStyle.knob = skin.newDrawable("knobS");
skin.add("sunSlider", sliderStyle);
sunlightSlider = new Slider(0, 100, 1, false, sliderStyle);
stage.addActor(sunlightSlider);
sunlightSlider.setBounds(300, 300, 100, 10);
sunlightSlider.setDisabled(true);
sunlightSlider.setDebug(true);
And then else where:
stage.act(Math.min(Gdx.graphics.getDeltaTime(), 1 / 30f));
stage.draw();
But for some reason the pixmaps in the slider seem to be drawn at their actual size. This can be seen in the following picture (the green line is what it should be, from the debug):
For some reason the width seems to be constrained by sunlightSlider.setBounds(300, 300, 100, 10); but the height does not.
I know that I could choose the pixmap size to what ever I need, but I want to use an image from file. If I use a big image, then it overflows the bounds similarly.
I want it to look like it is above, but constrained to the green rectangle.
What am I doing wrong?

A TextureRegionDrawable, which is what you've created with your newDrawable calls, by default has a minimum size that matches its original pixel dimensions. The minimum size of the Drawable prevents the Slider widget from drawing it as small as it would like to fit it into its own bounds. So you can reduce the minimum size:
sliderStyle.disabledBackground = skin.newDrawable("sliderBackS");
sliderStyle.disabledBackground.setMinWidth(0);
sliderStyle.disabledBackground.setMinHeight(0);
// and so on for other new drawables.
I'm not sure what your long term plans are, but typically you want all your skin's images to be part of a single Texture object so the SpriteBatch doesn't have to flush itself many times to draw your whole scene.
If for some reason you're not doing that, you can at least make all these solid color drawables use the same texture. It can simply be a one-pixel white texture that is shared by everything. Also, make sure you are disposing of the pixmap you use to create a texture, or you are leaking memory!
Pixmap pix = new Pixmap(1, 1, Pixmap.Format.RGBA8888);
pix.setColor(Color.WHITE);
pix.fill();
Texture tex = new Texture(pix);
pix.dispose();
skin.add(tex, "white");
Drawable blackDrawable = skin.newDrawable("white", Color.BLACK);
Drawable redDrawable = skin.newDrawable("white", Color.RED);
Slider.SliderStyle sliderStyle = new Slider.SliderStyle();
sliderStyle.disabledBackground = blackDrawable;
sliderStyle.disabledKnob = redDrawable;
sliderStyle.background = blackDrawable;
sliderStyle.knob = redDrawable;
Since you passed your Texture object to the Skin, the Skin will dispose of it when the Skin is disposed. Don't forget to dispose of the Skin in the dipose() method.

Java iText Rotate a Link Rectangle

I need to rotate a link rectangle using Java iText.
The original link rectangle appears in red. The rotated link rectangle appears in green.
My code:
PdfReader reader = new PdfReader( "input/blank.pdf" );
PdfStamper stamper = new PdfStamper( reader, new FileOutputStream( "output/blank_stamped.pdf" ) );
Rectangle linkLocation = new Rectangle( 100, 700, 100 + 200, 700 + 25 );
PdfName highlight = PdfAnnotation.HIGHLIGHT_INVERT;
PdfAnnotation linkRed = PdfAnnotation.createLink( stamper.getWriter(), linkLocation, highlight, "red" );
PdfAnnotation linkGreen = PdfAnnotation.createLink( stamper.getWriter(), linkLocation, highlight, "green" );
BaseColor baseColorRed = new BaseColor(255,0,0);
BaseColor baseColorGreen = new BaseColor(0,255,0);
linkRed.setColor(baseColorRed);
linkGreen.setColor(baseColorGreen);
double angleDegrees = 10;
double angleRadians = Math.PI*angleDegrees/180;
stamper.addAnnotation(linkRed, 1);
linkGreen.applyCTM(AffineTransform.getRotateInstance(angleRadians));
stamper.addAnnotation(linkGreen, 1);
stamper.close();
But this code does not rotate the recangle.

Please take a look at the following screen shot:
I have added 5 annotations to a simple Hello World file.
The first two are link annotations. Their position is defined by the rectangles linkLocation1 and linkLocation2:
Rectangle linkLocation1 = new Rectangle(30, 770, 120, 800);
PdfAnnotation link1 = PdfAnnotation.createLink(stamper.getWriter(),
linkLocation1, PdfAnnotation.HIGHLIGHT_INVERT, action);
link1.setColor(BaseColor.RED);
stamper.addAnnotation(link1, 1);
Rectangle linkLocation2 = new Rectangle(30, 670, 60, 760);
PdfAnnotation link2 = PdfAnnotation.createLink(stamper.getWriter(),
linkLocation2, PdfAnnotation.HIGHLIGHT_INVERT, action);
link2.setColor(BaseColor.GREEN);
stamper.addAnnotation(link2, 1);
The green rectangle looks like a rotated version of the red rectangle, but that's not really true: we just defined the "clickable" area that way. I don't understand why you'd want to get this effect by introducing a rotation. Why? Because a rotation always needs a rotating point. Suppose that you would introduce a rotation, what would be your rotation point? The (0, 0) coordinate? That would lead to strange results, wouldn't it?
Introducing a rotation for does make sense for some types of annotations though. In my example, I introduced three stamp annotations:
Rectangle linkLocation3 = new Rectangle(150, 770, 240, 800);
PdfAnnotation stamp1 = PdfAnnotation.createStamp(stamper.getWriter(), linkLocation3, "Landscape", "Confidential");
stamper.addAnnotation(stamp1, 1);
Rectangle linkLocation4 = new Rectangle(150, 670, 240, 760);
PdfAnnotation stamp2 = PdfAnnotation.createStamp(stamper.getWriter(), linkLocation4, "Portrait", "Confidential");
stamp2.setRotate(90);
stamper.addAnnotation(stamp2, 1);
Rectangle linkLocation5 = new Rectangle(250, 670, 340, 760);
PdfAnnotation stamp3 = PdfAnnotation.createStamp(stamper.getWriter(), linkLocation5, "Portrait", "Confidential");
stamp3.setRotate(45);
stamper.addAnnotation(stamp3, 1);
In this case, I introduce a rotation angle using the setRotate() method. This rotates the CONFIDENTIAL stamp inside the rectangle we defined. As you can see, this makes sense because the annotation does have actual content: the rotation has an impact on the way you read the word CONFIDENTIAL. In the case of the clickable area of the link annotation, there is no such content to be rotated.
If this doesn't answer your question, please rephrase your question because I don't think anyone can answer it in its current state.
Update
Please take a look at ISO-32000-1 aka the PDF specification. You'll discover that a rectangle is defined using 4 values: the x and y coordinate of the lower-left corner of the rectangle and the x and y coordinate of the upper-right corner of the rectangle. These are the two starting points of the horizontal and vertical sides. You want a rectangle that has sides that aren't horizontal/vertical. Obviously that isn't possible as you'd need the coordinates of 4 corner points to achieve that (8 values, not 4). You can achieve this using a polygon defined by QuadPoints.
See ITextShape Clickable Polygon or path

Android Touch Bounding Rectangle and Texture Location

Just using the coord system my rectangle for my touch bounding box never seems to align with the coordinated and placement of my textures.
What is the simplest way to draw bounding box rectangles so that I can line them up with my drawn textures?
Im using OPEN-GLES
EG..
playBounds = new Rectangle( 240, 400, 157, 177);
batcher.drawSprite(240, 400, 157, 177, Assets.mainMenu);

I found out that because the bounding rectangles are based on the lower left corner and texture coords are based on the center, the below seems to be the best solution.
playBounds = new Rectangle(240, 400, 157, 177);
batcher.drawSprite(
playBounds.lowerLeft.x + playBounds.width / 2,
playBounds.lowerLeft.y + playBounds.height / 2,
playBounds.width,
playBounds.height,
Assets.mainMenu
);

How to treat a shape painted with an algorithm like an object?

Ok dear folks, i've got this question and i don't really know a certain way to solve it.
I'm doing like a "Paint application" in java, i know everything is ready, but I need to paint the shapes with Computer Graphics Algorithms.
So, the thing is, once the shape is painted in the container how could I convert it like sort of an "Object" to be able to select the shape and move it around (I have to move it with another algorithm) I just want to know how could I know that some random point clicked in the screen belongs to an object, knowing that, I would be able to fill it(with algorithm).
I was thinking that having a Point class, and a shape class, if i click on the screen, get the coordinates and look within all the shapes and their points, but this may not be very efficient.
Any ideas guys ?
Thanks for the help.
Here is some of my code:
public class Windows extends JFrame{
private JPanel panel;
private JLabel etiqueta,etiqueta2;
public Windows() {
initcomp();
}
public void initcomp()
{
panel = new JPanel();
panel.setBounds(50, 50, 300, 300);
etiqueta = new JLabel("Circulo Trigonometrico");
etiqueta.setBounds(20, 40, 200, 30);
etiqueta2 = new JLabel("Circulo Bresenham");
etiqueta2.setBounds(150, 110, 200, 30);
panel.setLayout(null);
panel.add(etiqueta);
panel.add(etiqueta2);
panel.setBackground(Color.gray);
this.add(panel);
this.setLayout(null);
this.setVisible(true);
this.setSize(400,400);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public void paint(Graphics g){
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.red);
g2d.setStroke(new BasicStroke(2));
dibujarCirculo_bresenham(g2d, 50, 260, 260);
dibujarCirculo_trigonometrico(g2d, 50, 130, 200);
}
/*This functions paints a Circle*/
public void dibujarCirculo_trigonometrico(Graphics g,int R,int xc,int yc)
{
int x,y;
for (int i = 0; i < 180; i++) {
double angulo = Math.toRadians(i);
x = (int) (Math.cos(angulo)*R);
y = (int) (Math.sin(angulo)*R);
g.drawLine(x+xc, y+yc, x+xc, y+yc);
g.drawLine((-x+xc), (-y+yc), (-x+xc), (-y+yc));
}
}

I assume that any image is a valid (isn't constrained to a particular set of shapes). To get an contiguous area with similar properties, try using a flood fill.
To colour in or move a particular shape around, you can use flood fill to determine the set of pixels and manipulate the set accordingly. You can set a tolerance for similar hue, etc so that it's not as rigid as in Paint, and becomes more like the magic selection tool in Photoshop.

There are a couple of approaches to take here depending on what precisely you want.
1) is to have objects, one for each drawn thing on screen, with classes like Circle and Rectangle and Polygon so on. They would define methods like paint (how to draw them on screen), isCLickInsideOf (is a click at this point on screen contained by this shape, given size/position/etc?) and so on. Then, to redraw the screen draw each object, and to test if an object is being clicked on ask each object what it thinks.
2) is, if objects have the property of being uniform in colour, you can grab all pixels that make up a shape when the user clicks on one of the pixels by using a floodfill algorithm. Then you can load these into some kind of data structure, move them around as the user moves the mouse around, etc. Also, if every object is guaranteed to have a unique colour, you can test which object is being clicked on by just looking at colour. (Libraries like OpenGL use a trick like this sometimes to determine what object you have clicked on - drawing each object as a flat colour on a hidden frame and testing what pixel colour under the mouse pointer is)