I want to move blocks with different x-positions without changing their shape by reducing the x-position.
I have tried to run the following code, but it seems like the blocks move to a tow position way to fast (correct potion and other i can't see where).
downBlocks=new Arraylist<Rectangle>;
for (DownBlocks downBlocks:getBlocks()){
if(Gdx.input.isTouched()) {
Vector3 touchPos = new Vector3();
touchPos.set(Gdx.input.getX(), Gdx.input.getY(), 0);
camera.unproject(touchPos);
downBlocks.x = (int) touchPos.x - downBlocks.x;
}
}
To do a drag, you need to remember the point where the finger last touched the screen so you can get a finger delta. And as a side note, avoid putting code inside your loop iteration if it only needs to be called once. It's wasteful to unproject the screen's touch point over and over for every one of your DownBlocks.
static final Vector3 VEC = new Vector3(); // reusuable static member to avoid GC churn
private float lastX; //member variable for tracking finger movement
//In your game logic:
if (Gdx.input.isTouching()){
VEC.set(Gdx.input.getX(), Gdx.input.getY(), 0);
camera.unproject(VEC);
}
if (Gdx.input.justTouched())
lastX = VEC.x; //starting point of drag
else if (Gdx.input.isTouching()){ // dragging
float deltaX = VEC.x - lastX; // how much finger has moved this frame
lastX = VEC.x; // for next frame
// Since you're working with integer units, you can round position
int blockDelta = (int)Math.round(deltaX);
for (DownBlocks downBlock : getBlocks()){
downBlock.x += blockDelta;
}
}
I don't recommend using integer units for your coordinates, though. If you are doing pixel art, then I recommend using floats for storing coordinates, and rounding off the coordinates only when drawing. That will reduce jerky-looking movement. If you are not using pixel art, I would just use float coordinates all the way. Here's a good article to help understand units.
I'm going through this tutorial
Whenever my mouse hovers over the cube created with this code (my version below), the Atmosphere and Stars disappear.
This is how it looks normally:
This is how it looks when I hover over the cube (Look at the atmosphere):
I'm not sure what is going on here.
/*
* Copyright (C) 2012 United States Government as represented by the Administrator of the
* National Aeronautics and Space Administration.
* All Rights Reserved.
*/
package gov.nasa.worldwindx.examples.tutorial;
import gov.nasa.worldwind.Configuration;
import gov.nasa.worldwind.avlist.AVKey;
import gov.nasa.worldwind.geom.*;
import gov.nasa.worldwind.layers.RenderableLayer;
import gov.nasa.worldwind.pick.PickSupport;
import gov.nasa.worldwind.render.*;
import gov.nasa.worldwind.util.OGLUtil;
import gov.nasa.worldwindx.examples.ApplicationTemplate;
import javax.media.opengl.*;
import java.awt.*;
/**
* Example of a custom {#link Renderable} that draws a cube at a geographic position. This class shows the simplest
* possible example of a custom Renderable, while still following World Wind best practices. See
* http://goworldwind.org/developers-guide/how-to-build-a-custom-renderable/ for a complete description of this
* example.
*
* #author pabercrombie
* #version $Id: Cube.java 691 2012-07-12 19:17:17Z pabercrombie $
*/
public class Cube extends ApplicationTemplate implements Renderable
{
/** Geographic position of the cube. */
protected Position position;
/** Length of each face, in meters. */
protected double size;
/** Support object to help with pick resolution. */
protected PickSupport pickSupport = new PickSupport();
// Determined each frame
protected long frameTimestamp = -1L;
protected OrderedCube currentFramesOrderedCube;
/**
* This class holds the Cube's Cartesian coordinates. An instance of it is added to the scene controller's ordered
* renderable queue during picking and rendering.
*/
protected class OrderedCube implements OrderedRenderable
{
/** Cartesian position of the cube, computed from
* {#link gov.nasa.worldwindx.examples.tutorial.Cube#position}. */
protected Vec4 placePoint;
/** Distance from the eye point to the cube. */
protected double eyeDistance;
/**
* The cube's Cartesian bounding extent.
*/
protected Extent extent;
public double getDistanceFromEye()
{
return this.eyeDistance;
}
public void pick(DrawContext dc, Point pickPoint)
{
// Use same code for rendering and picking.
this.render(dc);
}
public void render(DrawContext dc)
{
Cube.this.drawOrderedRenderable(dc, Cube.this.pickSupport);
}
}
public Cube(Position position, double sizeInMeters)
{
this.position = position;
this.size = sizeInMeters;
}
public void render(DrawContext dc)
{
// Render is called twice, once for picking and once for rendering. In both cases an OrderedCube is added to
// the ordered renderable queue.
OrderedCube orderedCube = this.makeOrderedRenderable(dc);
if (orderedCube.extent != null)
{
if (!this.intersectsFrustum(dc, orderedCube))
return;
// If the shape is less that a pixel in size, don't render it.
if (dc.isSmall(orderedCube.extent, 1))
return;
}
// Add the cube to the ordered renderable queue. The SceneController sorts the ordered renderables by eye
// distance, and then renders them back to front.
dc.addOrderedRenderable(orderedCube);
}
/**
* Determines whether the cube intersects the view frustum.
*
* #param dc the current draw context.
*
* #return true if this cube intersects the frustum, otherwise false.
*/
protected boolean intersectsFrustum(DrawContext dc, OrderedCube orderedCube)
{
if (dc.isPickingMode())
return dc.getPickFrustums().intersectsAny(orderedCube.extent);
return dc.getView().getFrustumInModelCoordinates().intersects(orderedCube.extent);
}
/**
* Compute per-frame attributes, and add the ordered renderable to the ordered renderable list.
*
* #param dc Current draw context.
*/
protected OrderedCube makeOrderedRenderable(DrawContext dc)
{
// This method is called twice each frame: once during picking and once during rendering. We only need to
// compute the placePoint, eye distance and extent once per frame, so check the frame timestamp to see if
// this is a new frame. However, we can't use this optimization for 2D continuous globes because the
// Cartesian coordinates of the cube are different for each 2D globe drawn during the current frame.
if (dc.getFrameTimeStamp() != this.frameTimestamp || dc.isContinuous2DGlobe())
{
OrderedCube orderedCube = new OrderedCube();
// Convert the cube's geographic position to a position in Cartesian coordinates. If drawing to a 2D
// globe ignore the shape's altitude.
if (dc.is2DGlobe())
{
orderedCube.placePoint = dc.getGlobe().computePointFromPosition(this.position.getLatitude(),
this.position.getLongitude(), 0);
}
else
{
orderedCube.placePoint = dc.getGlobe().computePointFromPosition(this.position);
}
// Compute the distance from the eye to the cube's position.
orderedCube.eyeDistance = dc.getView().getEyePoint().distanceTo3(orderedCube.placePoint);
// Compute a sphere that encloses the cube. We'll use this sphere for intersection calculations to determine
// if the cube is actually visible.
orderedCube.extent = new Sphere(orderedCube.placePoint, Math.sqrt(3.0) * this.size / 2.0);
// Keep track of the timestamp we used to compute the ordered renderable.
this.frameTimestamp = dc.getFrameTimeStamp();
this.currentFramesOrderedCube = orderedCube;
return orderedCube;
}
else
{
return this.currentFramesOrderedCube;
}
}
/**
* Set up drawing state, and draw the cube. This method is called when the cube is rendered in ordered rendering
* mode.
*
* #param dc Current draw context.
*/
protected void drawOrderedRenderable(DrawContext dc, PickSupport pickCandidates)
{
this.beginDrawing(dc);
try
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
if (dc.isPickingMode())
{
Color pickColor = dc.getUniquePickColor();
pickCandidates.addPickableObject(pickColor.getRGB(), this, this.position);
gl.glColor3ub((byte) pickColor.getRed(), (byte) pickColor.getGreen(), (byte) pickColor.getBlue());
}
// Render a unit cube and apply a scaling factor to scale the cube to the appropriate size.
gl.glScaled(this.size, this.size, this.size);
this.drawUnitCube(dc);
}
finally
{
this.endDrawing(dc);
}
}
/**
* Setup drawing state in preparation for drawing the cube. State changed by this method must be restored in
* endDrawing.
*
* #param dc Active draw context.
*/
protected void beginDrawing(DrawContext dc)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
int attrMask = GL2.GL_CURRENT_BIT | GL2.GL_COLOR_BUFFER_BIT;
gl.glPushAttrib(attrMask);
if (!dc.isPickingMode())
{
dc.beginStandardLighting();
gl.glEnable(GL.GL_BLEND);
OGLUtil.applyBlending(gl, false);
// Were applying a scale transform on the modelview matrix, so the normal vectors must be re-normalized
// before lighting is computed.
gl.glEnable(GL2.GL_NORMALIZE);
}
// Multiply the modelview matrix by a surface orientation matrix to set up a local coordinate system with the
// origin at the cube's center position, the Y axis pointing North, the X axis pointing East, and the Z axis
// normal to the globe.
gl.glMatrixMode(GL2.GL_MODELVIEW);
Matrix matrix = dc.getGlobe().computeSurfaceOrientationAtPosition(this.position);
matrix = dc.getView().getModelviewMatrix().multiply(matrix);
double[] matrixArray = new double[16];
matrix.toArray(matrixArray, 0, false);
gl.glLoadMatrixd(matrixArray, 0);
}
/**
* Restore drawing state changed in beginDrawing to the default.
*
* #param dc Active draw context.
*/
protected void endDrawing(DrawContext dc)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
if (!dc.isPickingMode())
dc.endStandardLighting();
gl.glPopAttrib();
}
/**
* Draw a unit cube, using the active modelview matrix to orient the shape.
*
* #param dc Current draw context.
*/
protected void drawUnitCube(DrawContext dc)
{
// Vertices of a unit cube, centered on the origin.
float[][] v = {{-0.5f, 0.5f, -0.5f}, {-0.5f, 0.5f, 0.5f}, {0.5f, 0.5f, 0.5f}, {0.5f, 0.5f, -0.5f},
{-0.5f, -0.5f, 0.5f}, {0.5f, -0.5f, 0.5f}, {0.5f, -0.5f, -0.5f}, {-0.5f, -0.5f, -0.5f}};
// Array to group vertices into faces
int[][] faces = {{0, 1, 2, 3}, {2, 5, 6, 3}, {1, 4, 5, 2}, {0, 7, 4, 1}, {0, 7, 6, 3}, {4, 7, 6, 5}};
// Normal vectors for each face
float[][] n = {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}, {-1, 0, 0}, {0, 0, -1}, {0, -1, 0}};
// Note: draw the cube in OpenGL immediate mode for simplicity. Real applications should use vertex arrays
// or vertex buffer objects to achieve better performance.
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
gl.glBegin(GL2.GL_QUADS);
try
{
for (int i = 0; i < faces.length; i++)
{
gl.glNormal3f(n[i][0], n[i][1], n[i][2]);
for (int j = 0; j < faces[0].length; j++)
{
gl.glVertex3f(v[faces[i][j]][0], v[faces[i][j]][1], v[faces[i][j]][2]);
}
}
}
finally
{
gl.glEnd();
}
}
protected static class AppFrame extends ApplicationTemplate.AppFrame
{
public AppFrame()
{
super(true, true, false);
RenderableLayer layer = new RenderableLayer();
Cube cube = new Cube(Position.fromDegrees(35.0, -120.0, 3000), 100000);
layer.addRenderable(cube);
getWwd().getModel().getLayers().add(layer);
}
}
public static void main(String[] args)
{
Configuration.setValue(AVKey.INITIAL_LATITUDE, 35.0);
Configuration.setValue(AVKey.INITIAL_LONGITUDE, -120.0);
Configuration.setValue(AVKey.INITIAL_ALTITUDE, 2550000);
Configuration.setValue(AVKey.INITIAL_PITCH, 45);
Configuration.setValue(AVKey.INITIAL_HEADING, 45);
ApplicationTemplate.start("World Wind Custom Renderable Tutorial", AppFrame.class);
}
}
I have reproduced the problem, both with the tutorial Cube class that is included in worldwind.jar and your Cube class that draws a helpfully larger cube.
I have traced the point at which the atmosphere disappears is when the hidden buffer for the GLCanvas is swapped within the WorldWind render code, so the problem is that for some reason the atmosphere and stars layers are not drawn on the hidden buffer during rendering in picking mode using your code.
I then found that the example with Cylinders included as gov.nasa.worldwindx.examples.Cylinders.class draws pickable 3D shapes (cylinders) on the globe and does not exhibit this problem (there are others - Boxes for example is extremely close to this tutorial).
I think that that the issue is with the implementation of OrderedRenderable in this tutorial example - in the Cylinders example, the actual Cylinder class extends RigidShape which in turn extends AbstractShape, which is the class that actually implements OrderedRenderable. It's definitely a bug. Maybe you can work from the Boxes example to get the functionality you need.
I ended up getting an answer on the worldwind forums: http://forum.worldwindcentral.com/showthread.php?46115-Worldwind-Custom-Renderable-Picking-Issue&p=125173
Add a gl push matrix call in the begin drawing method:
protected void beginDrawing(DrawContext dc)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
int attrMask = GL2.GL_CURRENT_BIT | GL2.GL_COLOR_BUFFER_BIT;
gl.glPushAttrib(attrMask);
if (!dc.isPickingMode())
{
dc.beginStandardLighting();
gl.glEnable(GL.GL_BLEND);
OGLUtil.applyBlending(gl, false);
// Were applying a scale transform on the modelview matrix, so the normal vectors must be re-normalized
// before lighting is computed.
gl.glEnable(GL2.GL_NORMALIZE);
}
// Multiply the modelview matrix by a surface orientation matrix to set up a local coordinate system with the
// origin at the cube's center position, the Y axis pointing North, the X axis pointing East, and the Z axis
// normal to the globe.
gl.glPushMatrix();
gl.glMatrixMode(GL2.GL_MODELVIEW);
Matrix matrix = dc.getGlobe().computeSurfaceOrientationAtPosition(this.position);
matrix = dc.getView().getModelviewMatrix().multiply(matrix);
double[] matrixArray = new double[16];
matrix.toArray(matrixArray, 0, false);
gl.glLoadMatrixd(matrixArray, 0);
}
And additionally, add a gl pop matrix call in the end drawing:
protected void endDrawing(DrawContext dc)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
if (!dc.isPickingMode())
dc.endStandardLighting();
gl.glPopMatrix();
gl.glPopAttrib();
}
move
if (!dc.isPickingMode())
dc.endStandardLighting();
from
protected void endDrawing(DrawContext dc)
after
gl.glLoadMatrixd(matrixArray, 0);
in
protected void beginDrawing(DrawContext dc)
I do a Mario like game with the libgdx library.
All works fine but sometime (especially when the camera goes fast) my TileMap has a little bug during the render.
A picture worth thousand word, so here it is : http://postimg.org/image/4tudtwewn/
I have tried to increment FPS, but there is no change. I have no idea where that is come from.
Here is my code :
public void show() {
TmxMapLoader loader = new TmxMapLoader();
this.plan = loader.load("maps/level-"+this.world+"-"+this.level+".tmx");
this.renderer = new OrthogonalTiledMapRenderer(this.plan);
...
public void render(float delta) {
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
this.renderer.render();// rendu de la carte
Batch batch = this.renderer.getSpriteBatch();
...
This happens when your Camera's position is not perfectly aligned with screen-space coordinates (pixels).
This results in some sprites being rounded to the next pixel while some other (that were connected to those) being rounded to the previous one, resulting in visible ugly glitches.
The easiest fix I could come up with is making sure that the Camera position is always perfectly aligned with screen-space coordinates.
public class TileMapCamera extends OrthographicCamera {
// Map tile size to round to
private int tileSize;
/**
* Create a pixel-perfect camera for a map with the specified tile size
* #param tileSize
*/
public TileMapCamera(int tileSize){
this.tileSize = tileSize;
}
#Override
public void update(){
// Round position to avoid glitches
float prevx = position.x;
float prevy = position.y;
position.x = (int)(position.x * tileSize) / (float)tileSize;
position.y = (int)(position.y * tileSize) / (float)tileSize;
super.update();
position.set(prevx, prevy, 0);
}
}
This works for a tile-based coordinate viewport:
mapViewport = new FitViewport(16, 15, new TileMapCamera(map.getProperties().get("tilewidth", Integer.class)));
If you're working with pixel-based coordinate viewports, you should round the camera position to the nearest integer instead.
I think its about the filtering.
This will help:
TiledMapRenderer Artifact
If the problem you are referring to, is the spacing you can fix when you import the tileset as it says Tenfour04
add or change pixel padding.
I want to rotate an Image in java, initialized with
playerimage = Toolkit.getDefaultToolkit().getImage("C:/Game/player.png"); //Load Player Image
drawed with:
Graphics2D g = buffer.createGraphics();
g.drawImage(playerimage, player.getX(), player.getY(), null); // Draw Player
Now, I want my playerimage, to rotate to my mouse, so it's basically looking to my mouse. How would I do this?
The first thing you'll need to do is get both the mouse pos and the player pos in the same coord system. When you get our mouse pos it will normally be in Screen Coords while your player maybe in your own 'World Coords' space. If the players position is tied directly to pixels then you can skip ahead.
Convert the Mouse Position to World coords..
mouseWorld.X = (mouseScreen.X / screenWidth) * worldWidth;
Once you are in the same coord system you need to find the angle required to rotate. This equation will change based on which way your Player art is facing, lets assume it is facing up the position X axis. Then you can just use the dot product to find the angle between where your player is facing and where the point is pointing.
The dot product is A(dot)B = mag(A) * mag(B) * cos (theta)
mag = magnitude of the vector
theta = angle between the two vectors
So if you normalize the vectors (make them length 1) then..
A(dot)B = 1 * 1 * cos(theta)
A(dot)B = cos(theta)
acos(A(dot)B) = theta
So lets do code...
Vector mouseVec(mouseWorld.X, mouseWorld.Y);
Vector playerVec(playerWorld.X, playerWorld.Y);
//You want to find the angle the player must turn, so pretend the player pos it the origin
mouseVec -= playerVec;
//Create a vector that represents which way your player art is facing
Vector facingVec(1, 0);
mouseVec.Normalize(); //Make their length 1
facingVec.Normalize();
double dotProd = mouseVec.dot(facing);
double angBetween = acos(dotProd);
then call 'rotate' and pass in the angBetween!
Double check that the units are correct, often acos will return 'radians' and the rotate function will take 'degrees' so you need to convert.
More vector info:
Vector Info
I'm building a 2D physics engine in Java using OpenGL (from LWJGL) to display the objects. The problem I am having is that the transformation matrices I apply to the frame seem to be getting applied in a different order to what it says that are.
/**
* Render the current frame
*/
private void render() {
GL11.glMatrixMode(GL11.GL_PROJECTION);
GL11.glLoadIdentity();
GL11.glOrtho(0, Display.getDisplayMode().getWidth(), 0, Display
.getDisplayMode().getHeight(), -1, 1);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_STENCIL_BUFFER_BIT);
GL11.glPushMatrix();
GL11.glTranslatef(Display.getDisplayMode().getWidth() / 2, Display
.getDisplayMode().getHeight() / 2, 0.0f);
renderFrameObjects();
GL11.glPopMatrix();
}
public void renderFrameObjects() {
Vector<ReactiveObject> objects = frame.getObjects();
for (int i = 0; i < objects.size(); i++) {
ReactiveObject currentObject = objects.get(i);
Mesh2D mesh = currentObject.getMesh();
GL11.glRotatef((float)(currentObject.getR() / Math.PI * 180), 0, 0, 1.0f);
GL11.glTranslated(currentObject.getX(), currentObject.getY(), 0);
GL11.glBegin(GL11.GL_POLYGON);
for (int j = 0; j < mesh.size(); j++) {
GL11.glVertex2d(mesh.get(j).x, mesh.get(j).y);
}
GL11.glEnd();
GL11.glTranslated(-currentObject.getX(), -currentObject.getY(), 0);
GL11.glRotatef((float)(-currentObject.getR() / Math.PI * 180), 0, 0, 1.0f);
}
}
In renderFrameObjects() I apply a rotation, a translation, draw the object (mesh coordinates are relative to the object's x, y), reverse the translation, and reverse the rotation. Yet the effect it gives when an object rotates (on collision) is similar to when one would apply a translation then a rotation (ie. rotates around a point at a radius). I can't seem to be able to figure this one out having tried various combinations of transformations.
Any help would be appreciated.
That is beacause they are applied to the local coordinate system of the object, not the object itself.
So the rotate rotates the coordinate system and the translation is applied within that rotated coordinate system.
BTW: Don't undo your matrix changes by applying negative transformations. Roundoff error's will accumulate and it probably is also less efficient then using glPushMatrix and glPopMatrix