Ghost objects - bulletphysics - bullet

I'm trying to implement a simple ghost object in bulletphysics, this is how I create the ghost objects:
btGhostPairCallback* ghostCall = new btGhostPairCallback();
world->getBroadphase()->getOverlappingPairCache()->setInternalGhostPairCallback(ghostCall);
btGhostObject* ghostObj = new btGhostObject();
btCollisionShape* shape = new btBoxShape(btVector3(ofGetWidth()+1000, ofGetHeight()+1000, 50));
ghostObj->setCollisionShape(shape);
btTransform trans;
trans.setIdentity();
trans.setOrigin(btVector3(0,0,-500));
ghostObj->setWorldTransform(trans);
ghostObj->setCollisionFlags( btCollisionObject::CF_NO_CONTACT_RESPONSE);
world->addCollisionObject(ghostObj,btBroadphaseProxy::SensorTrigger,btBroadphaseProxy::AllFilter & ~btBroadphaseProxy::SensorTrigger);
and this is how to try to find the collision:
btCollisionObject* obj = world->getCollisionObjectArray()[j];
btRigidBody* body = btRigidBody::upcast(obj);
btAlignedObjectArray < btCollisionObject* > objsInsidePairCachingGhostObject;
btAlignedObjectArray < btCollisionObject* >* pObjsInsideGhostObject = NULL;
btGhostObject* ghost = btGhostObject::upcast(obj);
if(ghost){
objsInsidePairCachingGhostObject.resize(0);
pObjsInsideGhostObject = &ghost->getOverlappingPairs();
cout << ghost->getNumOverlappingObjects() << endl;
but I always get a response that all my world objects are in collision with the ghost object.
Anyone can help me to get a functional simple ghost object?
thanks

From what little I understand of the GhostObject, you're overriding its default collision flags. Try changing this line
ghostObj->setCollisionFlags( btCollisionObject::CF_NO_CONTACT_RESPONSE);
to:
ghostObj->setCollisionFlags( ghostObj->getCollisionFlags() | btCollisionObject::CF_NO_CONTACT_RESPONSE);
HTH

While I agree that the collision flags should be set properly by adding the new flag to the existing set of flags I'd also like to point out that the parameter to btBoxShape is a btVector3 that defines the half-extents of the object. That means the width, height, and length are actually twice as large as those parameters.

Related

GMS2 returns instance_create_layer :: specified layer "text_layer" does not exist even though the layer exists how do i fix this?

heres the code
var _obj;
if (instance_exists(obj_text)) _obj = obj_txt_queued; else _obj = obj_text;
with (instance_create_layer(0, 0, "text_layer", _obj))
{
msg = argument[0];
if (instance_exists(other)) originInstance = other.id else originInstance = noone;
if (argument_count > 1) background = argument[1]; else background = 1;
}
with (obj_phae)
{ if (state != scr_player_state_lock)
{
lastState = state;
state = scr_player_state_lock;
}
}
[layers](https://i.stack.imgur.com/9u9tD.png)
I tried removing any extra rooms that were not needed and I tried changing the layer name to something else.
I also tried using var instance_create_layer() but that obviously didn't work
I'm a bit confused at this part:
with (instance_create_layer(0, 0, "text_layer", _obj))
Especially the with(), as that function will go through every object in the room if it sees an object within the parameter, since you suggested to create a new object with it, I'm surprised it doesn't create an infinite loop. Maybe it works, I've never tried it myself, but I think there's a more logical way to assign variables from one object to a newly created object.
Assuming you want to use the With() statement to address the variables within the _obj, I think you can manage something similair through this function:
var object = instance_create_layer(0, 0, "text_layer", _obj)
object.msg = argument[0];
object.originInstance = id
if (argument_count > 1) object.background = argument[1]; else object.background = 1;
It's probably a given at this point, but double-check that this part of code can only run if it's in the same room that has a layer called "text_layer"
In the worst case, you may also try out instance_create_depth() and use the build-in depth variable from the object instead of the layer names. Using depth is more flexible, but less organised than layers.

Using GraphView Library for functions to display multiple graphs

I'm currently developing an android app for reading out multiple sensor values via Bluetooth and display them in a graph. When I stumbled upon jjoe64's GraphViewLibrary, I knew this would fit my purposes perfectly. But now I'm kind of stuck. Basically, I wrote a little function that would generate and display the values of three sensors in 3 different graphs one under the other. This works just fine when the activity is started first, all three graphs a nicely rendered and displayed. But when I want to update the graphs with different values using the resetData()-method to render the new values in each graph, only the last of the three graphs is updated. Obviously, because it's the last graph generated using this rather simple function. My question is: Is there any other elegant way to use a function like mine for generating and updating all three graphs one after the other? I already tried to set the GraphView variable back to null and different combinations of removing and adding the view. Passing the function a individual GraphView-variable like graphView1, graphView2... does also not work.
Here is the function:
private GraphView graphView;
private GraphViewSeries graphViewSerie;
private Boolean graphExisting = false;
...
public void makeGraphs (float[] valueArray, String heading, int graphId) {
String graphNumber = "graph"+graphId;
int resId = getResources().getIdentifier(graphNumber,"id", getPackageName());
LinearLayout layout = (LinearLayout) findViewById(resId);
int numElements = valueArray.length;
GraphViewData[] data = new GraphViewData[numElements];
for (int c = 0; c<numElements; c++) {
data[c] = new GraphViewData(c+1, valueArray[c]);
Log.i(tag, "GraphView Graph"+graphId+": ["+(c+1)+"] ["+valueArray[c]+"].");
}
if (!graphExisting) {
// init temperature series data
graphView = new LineGraphView(
this // context
, heading // heading
);
graphViewSerie = new GraphViewSeries(data);
graphView.addSeries(graphViewSerie);
((LineGraphView) graphView).setDrawBackground(true);
graphView.getGraphViewStyle().setNumHorizontalLabels(numElements);
graphView.getGraphViewStyle().setNumVerticalLabels(5);
graphView.getGraphViewStyle().setTextSize(10);
layout.addView(graphView);
}
else {
//graphViewSerie = new GraphViewSeries(data);
//graphViewSerie.resetData(data);
graphViewSerie.resetData(new GraphViewData[] {
new GraphViewData(1, 1.2f)
, new GraphViewData(2, 1.4f)
, new GraphViewData(2.5, 1.5f) // another frequency
, new GraphViewData(3, 1.7f)
, new GraphViewData(4, 1.3f)
, new GraphViewData(5, 1.0f)
});
}
And this is the function-call depending on an previously generated array (which is being monitored to be filled with the right values):
makeGraphs(graphData[0], "TempHistory", 1);
makeGraphs(graphData[1], "AirHistory", 2);
makeGraphs(graphData[2], "SensHistory", 3);
graphExisting = true;
Any help and / or any feedback in general is greatly appreciated! Lots of thanks in advance!
EDIT / UPDATE:
Thanks to jjoe64's answer I was able to modify the function to work properly. I was clearly having a mistake in my thinking, since I thought I'd also be changing a GraphViewSeries-object I would handle my function as additional parameter (which I tried before). Of course this does not work. However, with this minor Improvements I managed to make this work using a Graphviewseries Array. To give people struggling with a similar problem an idea of what I had to change, here the quick-and-dirty draft of the solution.
I just changed
private GraphViewSeries graphViewSerie;
to
private GraphViewSeries graphViewSerie[] = new GraphViewSeries[3];
and access the right Series using the already given parameter graphId within the function (if-clause) like this:
int graphIndex = graphId - 1;
graphViewSerie[graphIndex] = new GraphViewSeries(data);
In the else-clause I'm updating the series likewise by calling
graphViewSerie[graphIndex].resetData(data);
So, once again many thanks for your support, jjoe64. I'm sorry I wasn't able to update the question earlier, but I did not find time for it.
of course it is not working correct, because you save always the latest graphseries-object in the member graphViewSerie.
First you have to store the 3 different graphviewseries (maybe via array or map) and then you have to access the correct graphviewseries-object in the else clause.

Increment multidimensional array in Java

I have a file to put in a multidimensional array. I have to put to [0] a date (long) and one of the dimensions must be incremented depending on the value of the second token.
Here's the code :
BufferedReader bufStatsFile = new BufferedReader(new FileReader(statsFile));
String line = null;
List<Long[]> stats = new ArrayList<Long[]>();
stats.add(new Long[11]);
int i = 0; // will be in a loop later
while((line = bufStatsFile.readLine()) != null) {
StringTokenizer st = new StringTokenizer(line,";");
while(st.hasMoreTokens()) {
stats.get(i)[0] = Long.parseLong(st.nextToken());
stats.get(i)[Integer.parseInt(st.nextToken())]++; // Here is the problematic line.
}
}
bufStatsFile.close();
But the incrementation doesn't work. Maybe it is because of my array which is probably not correct, but I didn't found another proper way to do that.
Ok. I have found and it was, of course, stupid.
The problem was in my array declaration. I did it like that :
List<Long[]> stats = new ArrayList<Long[]>();
stats.add(new Long[11]);
And then, I tried to increment an Object and not a long number.
So now, I just do it like this :
List<long[]> stats = new ArrayList<>();
stats.add(new long[11]);
And it's perfectly working.
Check that the elements in your file are numbers from 0 to 10. Why are you having a List if you are only manipulating the row 0?
Which exception are your code throwing away?

How can I pass controls as reference in Bada?

In the big picture I want to create a frame based application in Bada that has a single UI control - a label. So far so good, but I want it to display a number of my choosing and decrement it repeatedly every X seconds. The threading is fine (I think), but I can't pass the label pointer as a class variable.
//MyTask.h
//...
result Construct(Label* pLabel, int seconds);
//...
Label* pLabel;
//MyTask.cpp
//...
result
MyTask::Construct(Label* pLabel, int seconds) {
result r = E_SUCCESS;
r = Thread::Construct(THREAD_TYPE_EVENT_DRIVEN);
AppLog("I'm in da constructor");
this->pLabel = pLabel;
this->seconds = seconds;
return r;
}
//...
bool
Threading::OnAppInitializing(AppRegistry& appRegistry)
{
// ...
Label* pLabel = new Label();
pLabel = static_cast<Label*>(pForm->GetControl(L"IDC_LABEL1"));
MyTask* task = new MyTask();
task->Construct(&pLabel); // HERE IS THE ERROR no matching for Label**
task->Start();
// ...
}
The problem is that I have tried every possible combination of *, &, and just plain pLabel, known in Combinatorics...
It is not extremely important that I get this (it is just for training) but I am dying to understand how to solve the problem.
Have you tried:
task->Construct(pLabel, 0);
And by that I want to point out that you are missing the second parameter for MyTask::Construct.
No, I haven't. I don't know of a second parameter. But this problem is solved. If I declare a variable Object* __pVar, then the constructor should be Init(Object* pVar), and if I want to initialize an instance variable I should write
Object* pVar = new Object();
MyClass* mClass = new MyClass();
mClass->Construct(pVar);

Mystery coordinate offset on getCharBoundaries

I've ran into a weird problem with getCharBoundaries, I could not figure out what coordinate space the coordinates returned from the function was in. What ever I tried I could not get it to match up with what I expected.
So I made a new project and and added simple code to highlight the last charater in a textfield, and all of a sudden it worked fine. I then tried to copy over the TextField that had been causing me problems, into the new project. And now the same weird offset appeared 50px on the x axis. Everything else was spot on.
So after some headscracthing comparing the two TextFields, I simply can not see a difference in their properties or transformation.
So I was hoping that someone might now what property might affect the coordinates returned by getCharBoundaries.
I am using Flash CS4.
I've just had exactly the same problem and thought I'd help out by offering what my findings are. With a help from this thread, I tried to find everything that wasn't 'default' about the textfield I was using. I found that when I had switched my TextFormatAlign (or 'align' in the IDE) and TextFieldAutoSize properties to 'LEFT' as opposed to 'CENTER', it solved the problem.
A little late in the game perhaps, but worth knowing for anyone running into the same problem. This was the only thread I could find that raised the right flag...
Well the getCharBoundaries returns the boundaries in the textfield coordinate system. Where the origin is topleft corner of the textfield.
getCharBoundaries does not take into consideration the scrolling. you need to check if there are scrollbars on its parent (textarea) and if so relocate. One quick way of doing it is using localtoglobal and globaltolocal. Use the first to translate from the textfield coordinate system to the application coordinate system and then use the second to translate from the app coordinate system to the coordinate system of the parent of the textfield which is the textarea. I'm fine tuning a my method to get char boundaries i will publish it today on my blog
http://flexbuzz.blogspot.com/
Works For Me(tm) (Flex Builder AS3 project):
[Embed(systemFont="Segoe UI", fontWeight="bold", fontName="emb",
mimeType="application/x-font")]
private var EmbeddedFont:Class;
public function ScratchAs3()
{
stage.scaleMode = 'noScale';
stage.align = 'tl';
var m:Matrix = new Matrix(.8, .1, -.1, 1.1, 26, 78);
var t:TextField = new TextField();
t.autoSize = 'left';
t.wordWrap = false;
t.embedFonts = true;
t.defaultTextFormat = new TextFormat("emb", 100, 0, true);
t.transform.matrix = m;
t.text = "TEST STRING.";
addChild(t);
var r:Rectangle = t.getCharBoundaries(8);
var tl:Point = m.transformPoint(r.topLeft);
var tr:Point = m.transformPoint(new Point(r.right, r.top));
var bl:Point = m.transformPoint(new Point(r.left, r.bottom));
var br:Point = m.transformPoint(r.bottomRight);
graphics.beginFill(0xFF, .6);
graphics.moveTo(tl.x, tl.y);
graphics.lineTo(tr.x, tr.y);
graphics.lineTo(br.x, br.y);
graphics.lineTo(bl.x, bl.y);
graphics.lineTo(tl.x, tl.y);
}
To literally answer your question, it returns the coordinates in the TextField's coordinate system, not it's parent, and it is affected by DisplayObject.transform.matrix, which is the backing for the .x, .y, .scaleX, .scaleY, .width, .height, and .rotation properties.
What ever it was the solution was simple to add a new TextField, never found out what property screwed everything up.
The first answer is correct in most cases. However if your field is parented to another movie clip it may still return the wrong y coordinate. try this code:
//if this doesn't work:
myTextFormat = new TextFormat();
myTextFormat.align = TextFormatAlign.LEFT;
myFieldsParent.myField.autoSize = TextFieldAutoSize.LEFT;
myFieldsParent.myField.setTextFormat( myTextFormat);
//try this:
var x = myFieldsParent.myField.getCharBoundaries(o).x;
var y = myFieldsParent.myField.getCharBoundaries(o).y;
var myPoint:Point = new Point(myField.getCharBoundaries(o).x,myField.getCharBoundaries(o).y);
var pt:Point = new Point(myFieldsParent.myField.getCharBoundaries(o).x, myFieldsParent.myField.getCharBoundaries(o).y);
pt = myFieldsParent.myField.localToGlobal(pt);
//pt is the variable containing the coordinates of the char in the stage's coordinate space. You may still need to offset it with a fixed value but it should be constant.
I didn't test this code as I have adapted this example from code that is embedded into my project so I apologize if I'm missing something...

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