I want to draw a directed arrow line through Java.
At present, I am using java.awt.Line2D.Double class to draw a line
g2.setStroke(new BasicStroke(2.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL)); // g2 is an instance of Graphics2D
g2.draw(new Line2D.Double(x1,y1,x2,y2));
But only the line appears and no directed arrow appears. BasicStroke.Join_BEVEL is used to draw a directed arrow. It is applied when two line segments meet.
The line I am drawing meets the border of a rectangle but no directed arrow is drawn. Only a simple line is drawn.
Is there anything I am missing?
Although Pete's post is awesomely comprehensive, I'm using this method to draw a very simple line with a little triangle at its end.
// create an AffineTransform
// and a triangle centered on (0,0) and pointing downward
// somewhere outside Swing's paint loop
AffineTransform tx = new AffineTransform();
Line2D.Double line = new Line2D.Double(0,0,100,100);
Polygon arrowHead = new Polygon();
arrowHead.addPoint( 0,5);
arrowHead.addPoint( -5, -5);
arrowHead.addPoint( 5,-5);
// [...]
private void drawArrowHead(Graphics2D g2d) {
tx.setToIdentity();
double angle = Math.atan2(line.y2-line.y1, line.x2-line.x1);
tx.translate(line.x2, line.y2);
tx.rotate((angle-Math.PI/2d));
Graphics2D g = (Graphics2D) g2d.create();
g.setTransform(tx);
g.fill(arrowHead);
g.dispose();
}
The bevel is drawn between segments in a polyline if they are at certain angles. It has no bearing if you are drawing a line which happens to be drawn near some other pixels which are of a certain colour - once you've drawn the rectangle, the Graphics object doesn't know about the rectangle, it (in effect) only holds the pixels. ( or rather the image or OS window holds the pixels ).
To draw a simple arrow, draw a line for the stalk as you're doing, then a polyline for the vee. Nicer looking nicer arrows have curved sides and are filled.
You probably don't want to use bevel for the arrow head, as bevels are a flat; instead use the mitre option:
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
public class BevelArrows
{
public static void main ( String...args )
{
SwingUtilities.invokeLater ( new Runnable () {
BevelArrows arrows = new BevelArrows();
#Override
public void run () {
JFrame frame = new JFrame ( "Bevel Arrows" );
frame.add ( new JPanel() {
public void paintComponent ( Graphics g ) {
arrows.draw ( ( Graphics2D ) g, getWidth(), getHeight() );
}
}
, BorderLayout.CENTER );
frame.setSize ( 800, 400 );
frame.setDefaultCloseOperation ( JFrame.EXIT_ON_CLOSE );
frame.setVisible ( true );
}
} );
}
interface Arrow {
void draw ( Graphics2D g );
}
Arrow[] arrows = { new LineArrow(), new CurvedArrow() };
void draw ( Graphics2D g, int width, int height )
{
g.setRenderingHint ( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
g.setColor ( Color.WHITE );
g.fillRect ( 0, 0, width, height );
for ( Arrow arrow : arrows ) {
g.setColor ( Color.ORANGE );
g.fillRect ( 350, 20, 20, 280 );
g.setStroke ( new BasicStroke ( 20.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL ) );
g.translate ( 0, 60 );
arrow.draw ( g );
g.setStroke ( new BasicStroke ( 20.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER ) );
g.translate ( 0, 100 );
arrow.draw ( g );
g.setStroke ( new BasicStroke ( 20.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND ) );
g.translate ( 0, 100 );
arrow.draw ( g );
g.translate ( 400, -260 );
}
}
static class LineArrow implements Arrow
{
public void draw ( Graphics2D g )
{
// where the control point for the intersection of the V needs calculating
// by projecting where the ends meet
float arrowRatio = 0.5f;
float arrowLength = 80.0f;
BasicStroke stroke = ( BasicStroke ) g.getStroke();
float endX = 350.0f;
float veeX;
switch ( stroke.getLineJoin() ) {
case BasicStroke.JOIN_BEVEL:
// IIRC, bevel varies system to system, this is approximate
veeX = endX - stroke.getLineWidth() * 0.25f;
break;
default:
case BasicStroke.JOIN_MITER:
veeX = endX - stroke.getLineWidth() * 0.5f / arrowRatio;
break;
case BasicStroke.JOIN_ROUND:
veeX = endX - stroke.getLineWidth() * 0.5f;
break;
}
// vee
Path2D.Float path = new Path2D.Float();
path.moveTo ( veeX - arrowLength, -arrowRatio*arrowLength );
path.lineTo ( veeX, 0.0f );
path.lineTo ( veeX - arrowLength, arrowRatio*arrowLength );
g.setColor ( Color.BLUE );
g.draw ( path );
// stem for exposition only
g.setColor ( Color.YELLOW );
g.draw ( new Line2D.Float ( 50.0f, 0.0f, veeX, 0.0f ) );
// in practice, move stem back a bit as rounding errors
// can make it poke through the sides of the Vee
g.setColor ( Color.RED );
g.draw ( new Line2D.Float ( 50.0f, 0.0f, veeX - stroke.getLineWidth() * 0.25f, 0.0f ) );
}
}
static class CurvedArrow implements Arrow
{
// to draw a nice curved arrow, fill a V shape rather than stroking it with lines
public void draw ( Graphics2D g )
{
// as we're filling rather than stroking, control point is at the apex,
float arrowRatio = 0.5f;
float arrowLength = 80.0f;
BasicStroke stroke = ( BasicStroke ) g.getStroke();
float endX = 350.0f;
float veeX = endX - stroke.getLineWidth() * 0.5f / arrowRatio;
// vee
Path2D.Float path = new Path2D.Float();
float waisting = 0.5f;
float waistX = endX - arrowLength * 0.5f;
float waistY = arrowRatio * arrowLength * 0.5f * waisting;
float arrowWidth = arrowRatio * arrowLength;
path.moveTo ( veeX - arrowLength, -arrowWidth );
path.quadTo ( waistX, -waistY, endX, 0.0f );
path.quadTo ( waistX, waistY, veeX - arrowLength, arrowWidth );
// end of arrow is pinched in
path.lineTo ( veeX - arrowLength * 0.75f, 0.0f );
path.lineTo ( veeX - arrowLength, -arrowWidth );
g.setColor ( Color.BLUE );
g.fill ( path );
// move stem back a bit
g.setColor ( Color.RED );
g.draw ( new Line2D.Float ( 50.0f, 0.0f, veeX - arrowLength * 0.5f, 0.0f ) );
}
}
}
This is my approach, absolute Math only:
/**
* Draw an arrow line between two points.
* #param g the graphics component.
* #param x1 x-position of first point.
* #param y1 y-position of first point.
* #param x2 x-position of second point.
* #param y2 y-position of second point.
* #param d the width of the arrow.
* #param h the height of the arrow.
*/
private void drawArrowLine(Graphics g, int x1, int y1, int x2, int y2, int d, int h) {
int dx = x2 - x1, dy = y2 - y1;
double D = Math.sqrt(dx*dx + dy*dy);
double xm = D - d, xn = xm, ym = h, yn = -h, x;
double sin = dy / D, cos = dx / D;
x = xm*cos - ym*sin + x1;
ym = xm*sin + ym*cos + y1;
xm = x;
x = xn*cos - yn*sin + x1;
yn = xn*sin + yn*cos + y1;
xn = x;
int[] xpoints = {x2, (int) xm, (int) xn};
int[] ypoints = {y2, (int) ym, (int) yn};
g.drawLine(x1, y1, x2, y2);
g.fillPolygon(xpoints, ypoints, 3);
}
In the past, I've written the following method to create an an arrow shape, which I can then fill with ((Graphics2D) g).fill(shape);
public static Shape createArrowShape(Point fromPt, Point toPt) {
Polygon arrowPolygon = new Polygon();
arrowPolygon.addPoint(-6,1);
arrowPolygon.addPoint(3,1);
arrowPolygon.addPoint(3,3);
arrowPolygon.addPoint(6,0);
arrowPolygon.addPoint(3,-3);
arrowPolygon.addPoint(3,-1);
arrowPolygon.addPoint(-6,-1);
Point midPoint = midpoint(fromPt, toPt);
double rotate = Math.atan2(toPt.y - fromPt.y, toPt.x - fromPt.x);
AffineTransform transform = new AffineTransform();
transform.translate(midPoint.x, midPoint.y);
double ptDistance = fromPt.distance(toPt);
double scale = ptDistance / 12.0; // 12 because it's the length of the arrow polygon.
transform.scale(scale, scale);
transform.rotate(rotate);
return transform.createTransformedShape(arrowPolygon);
}
private static Point midpoint(Point p1, Point p2) {
return new Point((int)((p1.x + p2.x)/2.0),
(int)((p1.y + p2.y)/2.0));
}
Just in case if you want an non-programmatic arrow (I.e. for text purpose) in Fast way, you can use <html> code for making arrow as text, just put your HTML code inside .setText() method for a component. I have java 1.8u202 it works fine.
myLabel.setText("<html><body>←</body></html>");
this code ← is for left-pointing arrow
other arrow directions HTML code from This Website
void drawArrow(Graphics g1, double x1, double y1, double x2, double y2 ) {
Graphics2D ga = (Graphics2D) g1.create();
ga.drawLine((int)x1, (int)y1, (int)x2, (int)y2);
double l = Math.sqrt(Math.pow((x2 - x1), 2) + Math.pow((y2 - y1), 2));// line length
double d = l / 10; // arrowhead distance from end of line. you can use your own value.
double newX = ((x2 + (((x1 - x2) / (l) * d)))); // new x of arrowhead position on the line with d distance from end of the line.
double newY = ((y2 + (((y1 - y2) / (l) * d)))); // new y of arrowhead position on the line with d distance from end of the line.
double dx = x2 - x1, dy = y2 - y1;
double angle = (Math.atan2(dy, dx)); //get angle (Radians) between ours line and x vectors line. (counter clockwise)
angle = (-1) * Math.toDegrees(angle);// cconvert to degree and reverse it to round clock for better understand what we need to do.
if (angle < 0) {
angle = 360 + angle; // convert negative degrees to posative degree
}
angle = (-1) * angle; // convert to counter clockwise mode
angle = Math.toRadians(angle);// convert Degree to Radians
AffineTransform at = new AffineTransform();
at.translate(newX, newY);// transport cursor to draw arrowhead position.
at.rotate(angle);
ga.transform(at);
Polygon arrowHead = new Polygon();
arrowHead.addPoint(5, 0);
arrowHead.addPoint(-5, 5);
arrowHead.addPoint(-2, -0);
arrowHead.addPoint(-5, -5);
ga.fill(arrowHead);
ga.drawPolygon(arrowHead);
}
This is the code from Vicente Reig's great answer, simplified a little and packaged as a nice utility class.
import java.awt.*;
import java.awt.geom.AffineTransform;
public class Arrow
{
private final Polygon arrowHead = new Polygon ();
/**
* Create an arrow.
*
* #see https://stackoverflow.com/questions/2027613/how-to-draw-a-directed-arrow-line-in-java
*
* #param size Size of the arrow to draw.
*/
public Arrow (int size)
{
// create a triangle centered on (0,0) and pointing right
arrowHead.addPoint (size, 0);
arrowHead.addPoint (-size, -size);
arrowHead.addPoint (-size, size);
//arrowHead.addPoint (0, 0); // Another style
}
/**
* Draw the arrow at the end of a line segment. Drawing the line segment must be done by the caller, using whatever
* stroke and color is required.
*/
public void drawArrowHead (Graphics2D g, double x0, double y0, double x1, double y1)
{
final AffineTransform tx = AffineTransform.getTranslateInstance (x1, y1);
tx.rotate (Math.atan2 (y1 - y0, x1 - x0));
g.fill (tx.createTransformedShape (arrowHead));
}
}
Related
I'm trying to draw a rotated shape at a given point. To give an example, in the following image, the red rectangle is a non-rotated rectangle drawn at a point and then the blue rectangle is rotated and drawn at the same position. The blue rectangle is the outcome I'm aiming for.
I've been experimenting and trying different methods. Currently, here is what I used for the image:
Point point = new Point(300, 300);
Dimension dim = new Dimension(200, 100);
double radians = Math.toRadians(30);
g.setColor(new java.awt.Color(1f, 0f, 0f, .5f));
g.fillRect(point.x, point.y, dim.width, dim.height);
translate(g, dim, radians);
g.rotate(radians, point.getX(), point.getY());
g.setColor(new java.awt.Color(0f, 0f, 1f, .5f));
g.fillRect(point.x, point.y, dim.width, dim.height);
private static void translate(Graphics2D g, Dimension dim, double radians) {
if (radians > Math.toRadians(360)) {
radians %= Math.toRadians(360);
}
int xOffsetX = 0;
int xOffsetY = 0;
int yOffsetX = 0;
int yOffsetY = 0;
if (radians > 0 && radians <= Math.toRadians(90)) {
xOffsetY -= dim.getHeight();
} else if (radians > Math.toRadians(90) && radians <= Math.toRadians(180)) {
xOffsetX -= dim.getWidth();
xOffsetY -= dim.getHeight();
yOffsetY -= dim.getHeight();
} else if (radians > Math.toRadians(180) && radians <= Math.toRadians(270)) {
xOffsetX -= dim.getWidth();
yOffsetX -= dim.getWidth();
yOffsetY -= dim.getHeight();
} else {
yOffsetX -= dim.getWidth();
}
int x = rotateX(xOffsetX, xOffsetY, radians);
int y = rotateY(yOffsetX, yOffsetY, radians);
g.translate(x, y);
}
private static int rotateX(int x, int y, double radians) {
if (x == 0 && y == 0) {
return 0;
}
return (int) Math.round(x * Math.cos(radians) - y * Math.sin(radians));
}
private static int rotateY(int x, int y, double radians) {
if (x == 0 && y == 0) {
return 0;
}
return (int) Math.round(x * Math.sin(radians) + y * Math.cos(radians));
}
This works for rectangles but doesn't work for other types of shapes. I'm trying to figure out if there is a way to accomplish this for every type of shape. Also note that the code is just for testing purposes and there are a lot of bad practices in it, like calling Math.toRadians so much.
Something like this?
It can be achieved using a rotate transform first, then using the bounds of the rotated shape as a basis, the translate transform can be used to shift it back to meet the top most y and leftmost x values of the original rectangle.
See the getImage() method for one implementation of that.
int a = angleModel.getNumber().intValue();
AffineTransform rotateTransform = AffineTransform.getRotateInstance((a*2*Math.PI)/360d);
// rotate the original shape with no regard to the final bounds
Shape rotatedShape = rotateTransform.createTransformedShape(rectangle);
// get the bounds of the rotated shape
Rectangle2D rotatedRect = rotatedShape.getBounds2D();
// calculate the x,y offset needed to shift it to top/left bounds of original rectangle
double xOff = rectangle.getX()-rotatedRect.getX();
double yOff = rectangle.getY()-rotatedRect.getY();
AffineTransform translateTransform = AffineTransform.getTranslateInstance(xOff, yOff);
// shift the new shape to the top left of original rectangle
Shape rotateAndTranslateShape = translateTransform.createTransformedShape(rotatedShape);
Here is the complete source code:
import java.awt.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.EmptyBorder;
public class TransformedShape {
private JComponent ui = null;
JLabel output = new JLabel();
JToolBar tools = new JToolBar("Tools");
ChangeListener changeListener = (ChangeEvent e) -> {
refresh();
};
int pad = 5;
Rectangle2D.Double rectangle = new Rectangle2D.Double(pad,pad,200,100);
SpinnerNumberModel angleModel = new SpinnerNumberModel(30, 0, 90, 1);
public TransformedShape() {
initUI();
}
private BufferedImage getImage() {
int a = angleModel.getNumber().intValue();
AffineTransform rotateTransform = AffineTransform.getRotateInstance((a*2*Math.PI)/360d);
Shape rotatedShape = rotateTransform.createTransformedShape(rectangle);
Rectangle2D rotatedRect = rotatedShape.getBounds2D();
double xOff = rectangle.getX()-rotatedRect.getX();
double yOff = rectangle.getY()-rotatedRect.getY();
AffineTransform translateTransform = AffineTransform.getTranslateInstance(xOff, yOff);
Shape rotateAndTranslateShape = translateTransform.createTransformedShape(rotatedShape);
Area combinedShape = new Area(rotateAndTranslateShape);
combinedShape.add(new Area(rectangle));
Rectangle2D r = combinedShape.getBounds2D();
BufferedImage bi = new BufferedImage((int)(r.getWidth()+(2*pad)), (int)(r.getHeight()+(2*pad)), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = bi.createGraphics();
g.setRenderingHint(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY);
g.setRenderingHint(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY);
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.setColor(new Color(255,0,0,127));
g.fill(rectangle);
g.setColor(new Color(0,0,255,127));
g.fill(rotateAndTranslateShape);
g.dispose();
return bi;
}
private void addModelToToolbar(String label, SpinnerNumberModel model) {
tools.add(new JLabel(label));
JSpinner spinner = new JSpinner(model);
spinner.addChangeListener(changeListener);
tools.add(spinner);
}
public final void initUI() {
if (ui!=null) return;
ui = new JPanel(new BorderLayout(4,4));
ui.setBorder(new EmptyBorder(4,4,4,4));
ui.add(output);
ui.add(tools,BorderLayout.PAGE_START);
addModelToToolbar("Angle", angleModel);
refresh();
}
private void refresh() {
output.setIcon(new ImageIcon(getImage()));
}
public JComponent getUI() {
return ui;
}
public static void main(String[] args) {
Runnable r = () -> {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
ex.printStackTrace();
}
TransformedShape o = new TransformedShape();
JFrame f = new JFrame(o.getClass().getSimpleName());
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
};
SwingUtilities.invokeLater(r);
}
}
You have a shape, any shape.
You have a point (px,py) and you want to rotate the shape around this point and angle ag measured counter-clokwise.
For each point of the shape the proccess has three steps:
Translate to (px,py)
Rotate
Translate back to (0,0)
The translation is fully simple
xNew = xOld - px
yNew = yOld - py
The rotation is a bit less simple
xRot = xNew * cos(ag) - yNew * sin(ag)
yRot = xNew * sin(ag) + yNew * cos(ag)
Finally the translation back:
xDef = xRot + px
yDef = yRot + py
A bit of explanation: Any transformation can be seen in two ways: 1) I move the shape 2) I move the axis-system. If you think about it, you'll find that the trasnsformation is relative: seen from the axis point of view or seen from the shape point of view.
So, you can say "I want coordinates in the translated system", or you can also say "I want the coordinates of the translated shape".
It doesn't matter what point of view you chose, the equations are the same.
I'm explaining this so much, just to achieve you realize which is the positive direction of the angle: clockwise or counter-clockwise.
I've been working on this a while and feel so close! Should be easy, but I'm still new to this.
The skeleton hand data is being passed in as joints[KinectPV2.JointType_HandLeft] and can be accessed through joint.getX() and joint.getY(). I want to pass this data into the update function to replace mouseX and mouseY. I'm guessing I have to create global variables to access it within the update function or maybe I have to pass the skeleton data as parameters into the update function? How can I replace the mouse position data with the hand position?
import KinectPV2.*;
KinectPV2 kinect;
private class MyFluidData implements DwFluid2D.FluidData{
// update() is called during the fluid-simulation update step.
#Override
public void update(DwFluid2D fluid) {
float px, py, vx, vy, radius, vscale, temperature;
radius = 15;
vscale = 10;
px = width/2;
py = 50;
vx = 1 * +vscale;
vy = 1 * vscale;
radius = 40;
temperature = 1f;
fluid.addDensity(px, py, radius, 0.2f, 0.3f, 0.5f, 1.0f);
fluid.addTemperature(px, py, radius, temperature);
particles.spawn(fluid, px, py, radius, 100);
boolean mouse_input = mousePressed;
// add impulse: density + velocity, particles
if(mouse_input && mouseButton == LEFT){
radius = 15;
vscale = 15;
px = mouseX;
py = height-mouseY;
vx = (mouseX - pmouseX) * +vscale;
vy = (mouseY - pmouseY) * -vscale;
fluid.addDensity (px, py, radius, 0.25f, 0.0f, 0.1f, 1.0f);
fluid.addVelocity(px, py, radius, vx, vy);
particles.spawn(fluid, px, py, radius*2, 300);
}
// add impulse: density + temperature, particles
if(mouse_input && mouseButton == CENTER){
radius = 15;
vscale = 15;
px = mouseX;
py = height-mouseY;
temperature = 2f;
fluid.addDensity(px, py, radius, 0.25f, 0.0f, 0.1f, 1.0f);
fluid.addTemperature(px, py, radius, temperature);
particles.spawn(fluid, px, py, radius, 100);
}
// particles
if(mouse_input && mouseButton == RIGHT){
px = mouseX;
py = height - 1 - mouseY; // invert
radius = 50;
particles.spawn(fluid, px, py, radius, 300);
}
}
}
int viewport_w = 1280;
int viewport_h = 720;
int viewport_x = 230;
int viewport_y = 0;
int gui_w = 200;
int gui_x = 20;
int gui_y = 20;
int fluidgrid_scale = 3;
DwFluid2D fluid;
// render targets
PGraphics2D pg_fluid;
//texture-buffer, for adding obstacles
PGraphics2D pg_obstacles;
// custom particle system
MyParticleSystem particles;
// some state variables for the GUI/display
int BACKGROUND_COLOR = 0;
boolean UPDATE_FLUID = true;
boolean DISPLAY_FLUID_TEXTURES = false;
boolean DISPLAY_FLUID_VECTORS = false;
int DISPLAY_fluid_texture_mode = 0;
boolean DISPLAY_PARTICLES = true;
public void settings() {
size(viewport_w, viewport_h, P2D);
smooth(4);
}
public void setup() {
surface.setLocation(viewport_x, viewport_y);
// main library context
DwPixelFlow context = new DwPixelFlow(this);
context.print();
context.printGL();
// fluid simulation
fluid = new DwFluid2D(context, viewport_w, viewport_h, fluidgrid_scale);
// set some simulation parameters
fluid.param.dissipation_density = 0.999f;
fluid.param.dissipation_velocity = 0.99f;
fluid.param.dissipation_temperature = 0.80f;
fluid.param.vorticity = 0.10f;
fluid.param.timestep = 0.25f;
fluid.param.gridscale = 8f;
// interface for adding data to the fluid simulation
MyFluidData cb_fluid_data = new MyFluidData();
fluid.addCallback_FluiData(cb_fluid_data);
// pgraphics for fluid
pg_fluid = (PGraphics2D) createGraphics(viewport_w, viewport_h, P2D);
pg_fluid.smooth(4);
pg_fluid.beginDraw();
pg_fluid.background(BACKGROUND_COLOR);
pg_fluid.endDraw();
// pgraphics for obstacles
pg_obstacles = (PGraphics2D) createGraphics(viewport_w, viewport_h, P2D);
pg_obstacles.smooth(4);
pg_obstacles.beginDraw();
pg_obstacles.clear();
float radius;
radius = 200;
pg_obstacles.stroke(64);
pg_obstacles.strokeWeight(1);
pg_obstacles.fill(0);
pg_obstacles.rect(1*width/2f, 1*height/4f, radius, radius/2, 10);
pg_obstacles.stroke(64);
pg_obstacles.strokeWeight(1);
pg_obstacles.fill(0);
pg_obstacles.rect(1*width/3.5f, 1*height/2.5f, radius, radius/2, 10);
//// border-obstacle
//pg_obstacles.strokeWeight(20);
//pg_obstacles.stroke(64);
//pg_obstacles.noFill();
//pg_obstacles.rect(0, 0, pg_obstacles.width, pg_obstacles.height);
pg_obstacles.endDraw();
fluid.addObstacles(pg_obstacles);
// custom particle object
particles = new MyParticleSystem(context, 1024 * 1024);
kinect = new KinectPV2(this);
//Enables depth and Body tracking (mask image)
kinect.enableDepthMaskImg(true);
kinect.enableSkeletonDepthMap(true);
kinect.init();
background(0);
frameRate(60);
}
public void draw() {
PImage imgC = kinect.getDepthMaskImage();
image(imgC, 0, 0, 320, 240);
//get the skeletons as an Arraylist of KSkeletons
ArrayList<KSkeleton> skeletonArray = kinect.getSkeletonDepthMap();
//individual joints
for (int i = 0; i < skeletonArray.size(); i++) {
KSkeleton skeleton = (KSkeleton) skeletonArray.get(i);
//if the skeleton is being tracked compute the skleton joints
if (skeleton.isTracked()) {
KJoint[] joints = skeleton.getJoints();
color col = skeleton.getIndexColor();
fill(col);
stroke(col);
drawHandState(joints[KinectPV2.JointType_HandRight]);
drawHandState(joints[KinectPV2.JointType_HandLeft]);
}
}
// update simulation
if(UPDATE_FLUID){
fluid.addObstacles(pg_obstacles);
fluid.update();
particles.update(fluid);
}
// clear render target
pg_fluid.beginDraw();
pg_fluid.background(BACKGROUND_COLOR);
pg_fluid.endDraw();
// render fluid stuff
if(DISPLAY_FLUID_TEXTURES){
// render: density (0), temperature (1), pressure (2), velocity (3)
fluid.renderFluidTextures(pg_fluid, DISPLAY_fluid_texture_mode);
}
if(DISPLAY_FLUID_VECTORS){
// render: velocity vector field
fluid.renderFluidVectors(pg_fluid, 10);
}
if( DISPLAY_PARTICLES){
// render: particles; 0 ... points, 1 ...sprite texture, 2 ... dynamic points
particles.render(pg_fluid, BACKGROUND_COLOR);
}
// display
image(pg_fluid , 320, 0);
image(pg_obstacles, 320, 0);
// display number of particles as text
//String txt_num_particles = String.format("Particles %,d", particles.ALIVE_PARTICLES);
//fill(0, 0, 0, 220);
//noStroke();
//rect(10, height-10, 160, -30);
//fill(255,128,0);
//text(txt_num_particles, 20, height-20);
// info
//String txt_fps = String.format(getClass().getName()+ " [size %d/%d] [frame %d] [fps %6.2f]", fluid.fluid_w, fluid.fluid_h, fluid.simulation_step, frameRate);
//surface.setTitle(txt_fps);
}
//draw a ellipse depending on the hand state
void drawHandState(KJoint joint) {
noStroke();
handState(joint.getState());
//println(joint.getState());
pushMatrix();
translate(joint.getX(), joint.getY(), joint.getZ());
//println(joint.getX(), joint.getY(), joint.getZ());
ellipse(joint.getX(), joint.getY(), 70, 70);
popMatrix();
}
/*
Different hand state
KinectPV2.HandState_Open
KinectPV2.HandState_Closed
KinectPV2.HandState_Lasso
KinectPV2.HandState_NotTracked
*/
//Depending on the hand state change the color
void handState(int handState) {
switch(handState) {
case KinectPV2.HandState_Open:
fill(0, 255, 0);
break;
case KinectPV2.HandState_Closed:
fill(255, 0, 0);
break;
case KinectPV2.HandState_Lasso:
fill(0, 0, 255);
break;
case KinectPV2.HandState_NotTracked:
fill(100, 100, 100);
break;
}
}
I'm guessing I have to create global variables to access it within the update function or maybe I have to pass the skeleton data as parameters into the update function?
What happened when you tried those approaches?
Either approach sounds fine. You could store the variables in a sketch-level variable, set those variables from the kinect code, then use those variables in your drawing code. Or you could pass the variables as a parameter to the drawing code. Either should work fine. I'd probably go for the first approach because it sounds easier to me, but that's just my personal preference.
I suggest working in smaller chunks. Create a separate program that ignores the kinect for now. Create a hard-coded sketch-level variable that holds the same type of information you'd get from the kinect. Then write drawing code that uses that hard-coded variable to draw the frame. Get that working perfectly before you try adding the kinect code back in.
Then if you get stuck on a specific step, you can post a MCVE and we can go from there. Good luck.
I'm trying to draw a circle with a random center inside a big bigger circular surface. (I'm actually trying to simulate a human and his eyesight inside a room!) I need to draw a random line (call it line1) passing through its center which will intersect with the surface. line1 does not necessarily pass the center of circular surface. I also need to draw two lines forming 60 degree, facing on one side of line1. Can anyone help me with that?
I created an example of what I need to draw.
import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Point;
import java.util.Random;
import javax.swing.JFrame;
public class ShapeTest extends JFrame{
int width=500;
int height=500;
public ShapeTest(){
setSize(width,height);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String a[]){
new ShapeTest();
}
public void paint(Graphics g){
// Circular Surface
drawCircleByCenter(g, width/2, height/2, width/2);
Random r = new Random();
Point center = new Point();
center.x=r.nextInt(width/2);
center.y=r.nextInt(width/2);
drawCircleByCenter(g, center.x, center.y, width/15);
}
void drawCircleByCenter(Graphics g, int x, int y, int radius){
//g.setColor(Color.LIGHT_GRAY);
g.drawOval(x-radius, y-radius, 2*radius, 2*radius);
}
}
Start by changing your method to draw a circle based on its center and radius to a method which returns a Ellipse2D object representing the circle. This will allow us to do some clipping and other things with the shape besides just draw it.
Setting the clip to be the shape of your large circle prevents stray marks from being made where you don't want them (think "color inside the lines"). This is important because when we draw the circles and lines inside the big circle, some of them will be too big and would otherwise mark outside the bounds of the big circle.
Once we set the clip, we use the method Line2D getVector(Point2D, double, length) with an origin at the center of the large circle, a random angle and a random length (capped to keep the small blue circle inside the big circle). Think of this a random polar coordinate with the center of the large circle as the origin. The end point of this vector is used to mark the center of the small circle.
Using the center of the small circle as a starting point, we can generate two vectors in opposite directions (just negate the length of one to get it going the other direction) by using a random direction angle. We use a length equal to the diameter of the big circle to make certain that the lines will always go all the way up to the edge of the big circle (but not past, thanks to our clip).
We simply add 60 and 120 degrees to the angle of our blue dashed line and draw two green lines calculating the vectors the same way we did for the two blue dashed lines, except we don't need to create ones with negated lengths. We can also add a normal vector in for good measure simply by adding 90 degrees to the angle of the blue dashed line.
Lastly, we pick some random polar coordinates (just like we did for the small blue circle) to represent some people, and using the intersection of the people with the areas created by the various lines, we can see where they are at and draw them up with color coded values.
Now that we have all the people, we eliminate the clip and draw the big circle and voila!
Check out Draw a line at a specific angle in Java for details on how I calculated the vectors for the lines.
But enough talk, here's the code:
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Line2D;
import java.awt.geom.Path2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class ShapeTest extends JFrame {
private static final long serialVersionUID = 1L;
private int width = 500;
private int height = 500;
private int padding = 50;
private BufferedImage graphicsContext;
private JPanel contentPanel = new JPanel();
private JLabel contextRender;
private Stroke dashedStroke = new BasicStroke(3.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND, 2f, new float[] {3f, 3f}, 0f);
private Stroke solidStroke = new BasicStroke(3.0f);
private RenderingHints antialiasing;
private Random random = new Random();
public static void main(String[] args) {
//you should always use the SwingUtilities.invodeLater() method
//to perform actions on swing elements to make certain everything
//is happening on the correct swing thread
Runnable swingStarter = new Runnable()
{
#Override
public void run(){
new ShapeTest();
}
};
SwingUtilities.invokeLater(swingStarter);
}
public ShapeTest(){
antialiasing = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
graphicsContext = new BufferedImage(width + (2 * padding), width + (2 * padding), BufferedImage.TYPE_INT_RGB);
contextRender = new JLabel(new ImageIcon(graphicsContext));
contentPanel.add(contextRender);
contentPanel.setSize(width + padding * 2, height + padding * 2);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setResizable(false);
this.setContentPane(contentPanel);
//take advantage of auto-sizing the window based on the size of its contents
this.pack();
this.setLocationRelativeTo(null);
this.paint();
setVisible(true);
}
public void paint() {
Graphics2D g2d = graphicsContext.createGraphics();
g2d.setRenderingHints(antialiasing);
//Set up the font to print on the circles
Font font = g2d.getFont();
font = font.deriveFont(Font.BOLD, 14f);
g2d.setFont(font);
FontMetrics fontMetrics = g2d.getFontMetrics();
//clear the background
g2d.setColor(Color.WHITE);
g2d.fillRect(0, 0, graphicsContext.getWidth(), graphicsContext.getHeight());
//set up the large circle
Point2D largeCircleCenter = new Point2D.Double((double)width / 2 + padding, (double)height / 2 + padding);
double largeCircleRadius = (double)width / 2;
Ellipse2D largeCircle = getCircleByCenter(largeCircleCenter, largeCircleRadius);
//here we build the small circle
Point2D smallCircleCenter = new Point2D.Double();
double smallCircleRadius = 15;
//we need to make certain it is confined inside the larger circle
//so we choose the following values carefully
//we want to go a random direction from the circle, so chose an
//angle randomly in any direction
double smallCenterVectorAngle = random.nextDouble() * 360.0d;
//and we want to be a random distance from the center of the large circle, but
//we limit the distance based on the radius of the small circle to prevent it
//from appearing outside the large circle
double smallCenterVectorLength = random.nextDouble() * (largeCircleRadius - smallCircleRadius);
Line2D vectorToSmallCenter = getVector(largeCircleCenter, smallCenterVectorAngle, smallCenterVectorLength);
//the resulting end point of the vector is a random distance from the center of the large circle
//in a random direction, and guaranteed to not place the small circle outside the large
smallCircleCenter.setLocation(vectorToSmallCenter.getP2());
Ellipse2D smallCircle = getCircleByCenter(smallCircleCenter, smallCircleRadius);
//before we draw any of the circles or lines, set the clip to the large circle
//to prevent drawing outside our boundaries
g2d.setClip(largeCircle);
//chose a random angle for the line through the center of the small circle
double angle = random.nextDouble() * 360.0d;
//we create two lines that start at the center and go out at the angle in
//opposite directions. We use 2*largeCircleRadius to make certain they
//will be large enough to fill the circle, and the clip we set prevent stray
//marks outside the big circle
Line2D centerLine1 = getVector(smallCircleCenter, angle, largeCircleRadius * 2);
Line2D centerLine2 = getVector(smallCircleCenter, angle, -largeCircleRadius * 2);
//now we just add 20 and 120 to our angle for the center-line, start at the center
//and again, use largeCircleRadius*2 to make certain the lines are big enough
Line2D sightVector1 = getVector(smallCircleCenter, angle + 60, largeCircleRadius * 2);
Line2D sightVector2 = getVector(smallCircleCenter, angle + 120, largeCircleRadius * 2);
Path2D visible = new Path2D.Double();
visible.moveTo(sightVector1.getX2(), sightVector1.getY2());
visible.lineTo(smallCircleCenter.getX(), smallCircleCenter.getY());
visible.lineTo(sightVector2.getX2(), sightVector2.getY2());
visible.closePath();
Path2D greenSide = new Path2D.Double();
greenSide.moveTo(centerLine1.getX2(), centerLine1.getY2());
greenSide.lineTo(smallCircleCenter.getX(), smallCircleCenter.getY());
greenSide.lineTo(centerLine2.getX2(), centerLine2.getY2());
greenSide.lineTo(sightVector1.getX2(), sightVector1.getY2());
greenSide.closePath();
int personCount = 5;
Area visibleArea = new Area(visible);
visibleArea.intersect(new Area(largeCircle));
Area greenSideArea = new Area(greenSide);
greenSideArea.intersect(new Area(largeCircle));
//we create a list of the people in the circle to
//prevent overlap
ArrayList<Shape> people = new ArrayList<Shape>();
people.add(smallCircle);
int i = 0;
personLoop: while (i < personCount){
double personCenterVectorAngle = random.nextDouble() * 360.0d;
double personCenterVectorLength = random.nextDouble() * (largeCircleRadius - smallCircleRadius);
Line2D vectorToPersonCenter = getVector(largeCircleCenter, personCenterVectorAngle, personCenterVectorLength);
Point2D personCircleCenter = vectorToPersonCenter.getP2();
Ellipse2D personCircle = getCircleByCenter(personCircleCenter, smallCircleRadius);
//this little loop lets us skip a person if they have overlap
//with another person, since people don't generally overlap
Area personArea = new Area(personCircle);
for (Shape person : people)
{
Area overlapArea = new Area(person);
overlapArea.intersect(personArea);
//this means that we have found a conflicting
//person, so should skip them
if (!overlapArea.isEmpty()){
continue personLoop;
}
}
people.add(personCircle);
personArea.intersect(visibleArea);
Area greenSideAreaTest = new Area(personCircle);
greenSideAreaTest.intersect(greenSideArea);
if (personArea.isEmpty()){
if (greenSideAreaTest.isEmpty()){
g2d.setColor(Color.orange);
System.out.println("Person " + i + " is behind the blue line");
}
else {
System.out.println("Person " + i + " is in front of the blue line");
g2d.setColor(Color.cyan);
}
}
else
{
System.out.println("Person " + i + " is between the green lines");
g2d.setColor(Color.magenta);
}
//alternatively to circles intersecting the area of interest, we can check whether the center
//is in the area of interest which may make more intuitive sense visually
// if (visibleArea.contains(personCircleCenter)){
// System.out.println("Person " + i + " is between the green lines");
// g2d.setColor(Color.magenta);
// }
// else {
// if (greenSideArea.contains(personCircleCenter)) {
// System.out.println("Person " + i + " is in front of the blue line");
// g2d.setColor(Color.cyan);
// }
// else{
// g2d.setColor(Color.orange);
// System.out.println("Person " + i + " is behind the blue line");
// }
// }
g2d.fill(personCircle);
g2d.setColor(Color.black);
String itemString = "" + i;
Rectangle2D itemStringBounds = fontMetrics.getStringBounds(itemString, g2d);
double textX = personCircleCenter.getX() - (itemStringBounds.getWidth() / 2);
double textY = personCircleCenter.getY() + (itemStringBounds.getHeight()/ 2);
g2d.drawString("" + i, (float)textX, (float)textY);
i++;
}
//fill the small circle with blue
g2d.setColor(Color.BLUE);
g2d.fill(smallCircle);
//draw the two center lines lines
g2d.setStroke(dashedStroke);
g2d.draw(centerLine1);
g2d.draw(centerLine2);
//create and draw the black offset vector
Line2D normalVector = getVector(smallCircleCenter, angle + 90, largeCircleRadius * 2);
g2d.setColor(Color.black);
g2d.draw(normalVector);
//draw the offset vectors
g2d.setColor(new Color(0, 200, 0));
g2d.draw(sightVector1);
g2d.draw(sightVector2);
//we save the big circle for last, to cover up any stray marks under the stroke
//of its perimeter. We also set the clip back to null to prevent the large circle
//itselft from accidentally getting clipped
g2d.setClip(null);
g2d.setStroke(solidStroke);
g2d.setColor(Color.BLACK);
g2d.draw(largeCircle);
g2d.dispose();
//force the container for the context to re-paint itself
contextRender.repaint();
}
private static Line2D getVector(Point2D start, double degrees, double length){
//we just multiply the unit vector in the direction we want by the length
//we want to get a vector of correct direction and magnitute
double endX = start.getX() + (length * Math.sin(Math.PI * degrees/ 180.0d));
double endY = start.getY() + (length * Math.cos(Math.PI * degrees/ 180.0d));
Point2D end = new Point2D.Double(endX, endY);
Line2D vector = new Line2D.Double(start, end);
return vector;
}
private static Ellipse2D getCircleByCenter(Point2D center, double radius)
{
Ellipse2D.Double myCircle = new Ellipse2D.Double(center.getX() - radius, center.getY() - radius, 2 * radius, 2 * radius);
return myCircle;
}
}
The logic of the geometry turned out to be more tricky than I'd presumed, but this is what I think you are after.
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.swing.*;
class HumanEyesightLines {
int rad = 150;
int radSmall = 15;
int pad = 10;
JPanel gui = new JPanel(new BorderLayout());
BufferedImage img = new BufferedImage(
2 * (rad + pad),
2 * (rad + pad),
BufferedImage.TYPE_INT_RGB);
Timer timer;
JLabel imgDisplay;
Random rnd = new Random();
RenderingHints rh = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
HumanEyesightLines() {
imgDisplay = new JLabel(new ImageIcon(img));
gui.add(imgDisplay);
File f = new File(System.getProperty("user.home"));
final File f0 = new File("HumanEyesiteLines");
f0.mkdirs();
try {
Desktop.getDesktop().open(f0);
} catch (IOException ex) {
ex.printStackTrace();
}
ActionListener animationListener = new ActionListener() {
int ii = 0;
#Override
public void actionPerformed(ActionEvent e) {
paintImage();
ii++;
if (ii < 100) {
System.out.println(ii);
File f1 = new File(f0, "eg" + ii + ".png");
try {
ImageIO.write(img, "png", f1);
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
};
timer = new Timer(100, animationListener);
paintImage();
}
float[] dash = {3f, 3f};
float phase = 0f;
private final void paintImage() {
Graphics2D g = img.createGraphics();
g.setRenderingHints(rh);
g.setStroke(new BasicStroke(2f));
// fill the BG
g.setColor(Color.WHITE);
g.fillRect(0, 0, 2 * (rad + pad), 2 * (rad + pad));
// draw the big circle
Point center = new Point(rad + pad, rad + pad);
Shape bigCircle = new Ellipse2D.Double(pad, pad, 2 * rad, 2 * rad);
g.setColor(Color.MAGENTA.darker());
g.fill(bigCircle);
// set the clip to that of the big circle
g.setClip(bigCircle);
// draw the small circle
int xOff = rnd.nextInt(rad) - rad / 2;
int yOff = rnd.nextInt(rad) - rad / 2;
int x = center.x - xOff;
int y = center.y - yOff;
Shape smallCircle = new Ellipse2D.Double(
x - radSmall, y - radSmall,
2 * radSmall, 2 * radSmall);
g.setColor(Color.YELLOW);
g.fill(smallCircle);
g.setColor(Color.ORANGE);
g.draw(smallCircle);
g.setStroke(new BasicStroke(
1.5f,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_ROUND,
2f,
dash,
phase));
// I don't know what the rule is for where the blue line goes, so
// will use the top left corner of the image as a 2nd anchor point.
int x0 = 0;
int y0 = 0;
double grad = (double) (y - y0) / (double) (x - x0);
// now calculate the RHS point from y = mx + b
// where b = 0 and m is the gradient
int x1 = 2 * (pad + rad);
int y1 = (int) (grad * x1);
Line2D.Double line1 = new Line2D.Double(x0, y0, x1, y1);
g.setColor(Color.BLUE);
g.draw(line1);
//find the perpendicular gradient.
double perpGrad = -1d / grad;
double perpTheta = Math.atan(perpGrad);
// angle from perp
double diffTheta = Math.PI / 6d;
g.setColor(Color.GREEN);
double viewLine1Theta = perpTheta + diffTheta;
Line2D.Double viewLine1 = getLine(x, y, viewLine1Theta);
double viewLine2Theta = perpTheta - diffTheta;
Line2D.Double viewLine2 = getLine(x, y, viewLine2Theta);
g.draw(viewLine1);
g.draw(viewLine2);
g.setColor(Color.BLACK);
Line2D.Double viewPerp = getLine(x, y, perpTheta);
g.draw(viewPerp);
g.setColor(Color.RED);
g.draw(bigCircle);
g.dispose();
imgDisplay.repaint();
}
/**
* Returns a Line2D starting at the point x1,y1 at angle theta.
*/
private final Line2D.Double getLine(double x1, double y1, double theta) {
double m;
double b;
double x2;
double y2;
if (theta < (-Math.PI / 2d)) {
System.out.println("CHANGE IT! " + theta);
m = Math.tan(theta);
b = y1 - (m * x1);
x2 = 0;
y2 = (m * x2) + b;
} else {
m = Math.tan(theta);
b = y1 - (m * x1);
x2 = 2 * (rad + pad);
y2 = (m * x2) + b;
}
/*
* System.out.println("Perp theta: " + theta); System.out.println("Line
* grad: " + m); System.out.println("Line off: " + b);
* System.out.println("x1,y1: " + x1 + "," + y1);
* System.out.println("x2,y2: " + x2 + "," + y2);
*
*/
return new Line2D.Double(x1, y1, x2, y2);
}
public JComponent getGui() {
return gui;
}
public void start() {
timer.start();
}
public void stop() {
timer.stop();
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
HumanEyesightLines hel = new HumanEyesightLines();
hel.start();
JOptionPane.showMessageDialog(null, hel.getGui());
hel.stop();
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency
SwingUtilities.invokeLater(r);
}
}
So far, i have the code to get the mouse's position in the world, however i need to get it on a given plane (z=0), how can i go about doing this? Here is my picking code :
static public Vector3f getMousePositionIn3dCoords(int mouseX, int mouseY) {
viewport.clear();
modelview.clear();
projection.clear();
winZ.clear();;
position.clear();
float winX, winY;
GL11.glGetFloat( GL11.GL_MODELVIEW_MATRIX, modelview );
GL11.glGetFloat( GL11.GL_PROJECTION_MATRIX, projection );
GL11.glGetInteger( GL11.GL_VIEWPORT, viewport );
winX = (float)mouseX;
winY = (float)mouseY;
GL11.glReadPixels(mouseX, mouseY, 1, 1, GL11.GL_DEPTH_COMPONENT, GL11.GL_FLOAT, winZ);
float zz = winZ.get();
GLU.gluUnProject(winX, winY, zz, modelview, projection, viewport, position);
Vector3f v = new Vector3f(position.get(0),position.get(1),position.get(2));
return v ;
}
I've solved it, for anyone interested, here is my modified code for getting the x and y in the world when z=0 :
static public Vector3f getMouseOnPlaneZ(int mouseX, int mouseY)
{
viewport.clear();
modelview.clear();
projection.clear();
winZ.clear();;
position.clear();
float winX, winY;
GL11.glGetFloat( GL11.GL_MODELVIEW_MATRIX, modelview );
GL11.glGetFloat( GL11.GL_PROJECTION_MATRIX, projection );
GL11.glGetInteger( GL11.GL_VIEWPORT, viewport );
winX = (float)mouseX;
winY = (float)mouseY;
GLU.gluUnProject(winX, winY, 0.0f, modelview, projection, viewport, position);
GLU.gluUnProject(winX, winY, 1.0f, modelview, projection, viewport, position1);
float zeropoint, zeroperc;
double posXt, posYt, posZt;
posXt = position.get(0) - position1.get(0);
posYt = position.get(1) - position1.get(1);
posZt = position.get(2) - position1.get(2);
if ((position.get(2) < 0.0 && position1.get(2) < 0.0) || (position.get(2) > 0.0 && position1.get(2) > 0.0))
return null;
zeropoint = 0.0f - (float)position.get(2);
//Find the percentage that this point is between them
zeroperc = (zeropoint / (float)posZt);
Vector3f v = new Vector3f((float)position.get(0) + (float)(posXt * zeroperc),(float)position.get(1) + (float)(posYt * zeroperc),(float)position.get(2) + (float)(posZt * zeroperc));
return v ;
}
Hello guys I need to draw the curved lines in bold mainly those starting N - S and if possible the ones getting 350-10 340-20 and so on. I have tried QuadCurve2D and drawArc, but none of those worked. Is there any way possible to avoid the use of drawPolyline(xPoints, yPoints, WIDTH) because it will take hundreds of pairs to draw just one line.
This is part of the code in order to avoid your loss of time testing yourself :
public class PaintMyQuad extends JPanel {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
QuadCurve2D.Double curve = new QuadCurve2D.Double(200,0,200,100,200,200);
QuadCurve2D.Double curve1 = new QuadCurve2D.Double(200,0,180,100,200,200);
QuadCurve2D.Double curve2 = new QuadCurve2D.Double(200,0,160,100,200,200);
//etc
g2d.setColor(Color.RED);
g2d.draw(curve);
g2d.draw(curve1);
g2d.draw(curve2);
g2d.drawOval(100,100,200,200);
g2d.drawArc(100,100, 100, 200, 90, 180);
g2d.drawArc(100, 100, 100, 200, 180, 360);
g2d.drawArc(100, 100, 0, 200, 90, 180);
g2d.drawRect(100, 100, 200, 200);
If you need bold lines, try so:
....
Graphics2D g2d = (Graphics2D)g;
BasicStroke pen1 = new BasicStroke(5); // this is stroke with 5px width,
g2d.setStroke(pen1);
g2d.drawArc(100,100, 100, 200, 90, 180);
g2d.drawArc(100, 100, 100, 200, 180, 360);
...
Make 2 strokes for two types of lines, and use it.
Im not sure if this is an really an answer - but have I have run into a resolution problem. I have tried anti-aliasing but it looked worse.
One way you could do it is in the for loop put an if statement for odd and even numbers.Happy for some advice on this, I was thinking there maybe a better library to get nicer circles.
Maybe I'm doing it the old school way?
import java.awt.*;
import javax.swing.*;
public class Stereonet{
private static int centreX, centreY, radius;
private Color colour;
/**Stereonet template contructor takes 3 int parameters
* x, y for centre position and radius for stereonet radius*/
public Stereonet(int x , int y, int radius, Color colour){
centreX = x;
centreY = y;
this.radius = radius;
this.colour = colour;
}
public void draw(Graphics g){
Graphics2D g2D = (Graphics2D) g;
g2D.setStroke(new BasicStroke(2F));
g.setColor(colour);
g.drawOval(centreX - radius , centreY - radius, radius * 2 , radius * 2);
g2D.setStroke(new BasicStroke(1F));
g.drawLine(centreX, centreY - radius, centreX, centreX + radius);
g.drawLine(centreX - radius, centreY, centreX + radius, centreY);
g2D.setStroke(new BasicStroke(1F));
for(int degrees = 10; degrees <= 80; degrees += 10){
double greatRadius = radius / (Math.cos(Math.toRadians(degrees))); // radius of great circle
int greatX1 = (int)Math.round(centreX + radius * (Math.tan(Math.toRadians(degrees)))
- greatRadius); // x coord of great circle left hemisphere
int greatX2 = (int)Math.round(centreX - (radius * (Math.tan(Math.toRadians(degrees))))
- greatRadius); // x coord of great circle right hemisphere
int greatY = (int)Math.round(centreY - greatRadius); // y coord of great circle
double smallRadius = (radius / (Math.tan(Math.toRadians(degrees))));
int smallY1 = (int)Math.round((centreY - (radius / (Math.sin(Math.toRadians(degrees)))) - smallRadius));
int smallY2 = (int)Math.round((centreY + (radius / (Math.sin(Math.toRadians(degrees)))) - smallRadius));
int smallX = (int)Math.round(centreX - smallRadius);
g.drawArc(greatX1, greatY, 2 * (int)Math.round(greatRadius), 2 * (int)Math.round(greatRadius),
90 + degrees, 180 - ( 2 * degrees));
g.drawArc(greatX2, greatY, 2 * (int)Math.round(greatRadius), 2 * (int)Math.round(greatRadius),
270 + degrees, 180 - ( 2 * degrees));
g.drawArc(smallX, smallY1, 2 * (int)Math.round(smallRadius), 2 * (int)Math.round(smallRadius),
270 - degrees, 180 - ( 2 * (90 - degrees)));
g.drawArc(smallX, smallY2, 2 * (int)Math.round(smallRadius), 2 * (int)Math.round(smallRadius),
90 - degrees, 180 - ( 2 * (90 - degrees)));
}
}
public static int getRadius(){
return radius;
}
public static int getX(){
return centreX;
}
public static int getY(){
return centreY;
}