TouchDown

[gamecreator]

I have the following code:

 

context->DrawText("Touch down index 0: " + String(window->TouchDown(0)),5,0);
context->DrawText("Touch down index 1: " + String(window->TouchDown(1)),5,30);

 

It works mostly as I expect except for one situation.

 

If I hold one finger down and then a second, they both return one. If I lift my second finger and then the first, they both return to 0.

 

But

 

If after holding both fingers down I lift my first finger and then the second, index 0 returns 0 but index 1 is stuck at 1. If there are no fingers touching the device, shouldn't they both be 0?

[gamecreator]

More, when I update the code as this:

 

context->DrawText("Touch down index 0: " + String(window->TouchDown(0)) + "  pos: " + window->GetTouchPosition(0).ToString(),5,70);
context->DrawText("Touch down index 1: " + String(window->TouchDown(1)) + "  pos: " + window->GetTouchPosition(1).ToString(),5,100);

 

while holding down the both fingers and moving both, only index 0 updates continuously. Index 1 only updates when I put my finger down after having it up, but not while dragging it across the screen. Am I doing anything wrong or are these bugs?

[Josh]

Thank you. It is possible something is funky here.

[Admin]

This is on Android, right?

[gamecreator]

Yes (that's where the original thread was posted before it was moved to this forum).

[Admin]

Trying to charge a Nexus 7 to test this...

[Admin]

I can reproduce this behavior on a Nexus 7. That's a first step.

[Josh]

It appears the touch API is more complicated than I thought...

http://developer.android.com/reference/android/view/MotionEvent.html

[gamecreator]

Whoa. That's a lot of options. I hope that makes a ton more sense to you than it does to me. In any case, thank you for looking into it.

[Josh]

Makes absolutely no sense to me, but I will mess around with it and see what I get. Just bad design built on top of bad design.

[Josh]

Of course, their provided example code doesn't print anything out

 

The reason Android is free is because they could never charge for this.

 

void printSamples(MotionEvent ev) {
    final int historySize = ev.getHistorySize();
    final int pointerCount = ev.getPointerCount();
    for (int h = 0; h < historySize; h++) {
        System.out.printf("At time %d:", ev.getHistoricalEventTime(h));
        for (int p = 0; p < pointerCount; p++) {
            System.out.printf("  pointer %d: (%f,%f)",
                ev.getPointerId(p), ev.getHistoricalX(p, h), ev.getHistoricalY(p, h));
        }
    }
    System.out.printf("At time %d:", ev.getEventTime());
    for (int p = 0; p < pointerCount; p++) {
        System.out.printf("  pointer %d: (%f,%f)",
            ev.getPointerId(p), ev.getX(p), ev.getY(p));
    }
}

[Josh]

This is the program I am using to test:

#include "App.h"

using namespace Leadwerks;

App::App() : window(NULL), context(NULL), world(NULL), camera(NULL) {}

App::~App() { delete world; delete window; }

float angle=25;
Joint* joint;

bool App::Start()
{
       window = Window::Create();
       context = Context::Create(window);
       world = World::Create();
       camera = Camera::Create();
       camera->Move(0,0,-4);

       Font* font = Font::Load("Fonts/arial.ttf",36);
       context->SetFont(font);

       return true;
}

bool App::Loop()
{
       if (window->Closed() || window->KeyDown(Key::Escape)) return false;

       Time::Update();
       world->Update();

       context->SetColor(0,0,0,0);
       context->Clear();

       context->SetColor(1,1,1,1);
       context->SetBlendMode(Blend::Alpha);
       context->DrawText("Touch down index 0: " + String(window->TouchDown(0)),5,0);
       context->DrawText("Touch down index 1: " + String(window->TouchDown(1)),5,60);
       context->SetBlendMode(Blend::Solid);

       context->Sync();

       return true;
}

 

And I am using this code in AndroidActivity.Java:

	@Override
public boolean onTouchEvent(MotionEvent event) {
	//Integer activePointer = (event.getAction() >> MotionEvent.ACTION_POINTER_ID_SHIFT);
	//Integer activePointer = event.getActionIndex();

	for (int i=0; i<event.getPointerCount(); ++i)
	{
		//Integer activePointer = event.getPointerId(0);
		Integer mActivePointerId = event.getPointerId(i);
		Integer activePointer = event.findPointerIndex(mActivePointerId);

		Float x = event.getX(i);
		Float y = event.getY(i);

		switch (event.getAction() & MotionEvent.ACTION_MASK) {
		case MotionEvent.ACTION_DOWN:
		case MotionEvent.ACTION_POINTER_DOWN:
			// Log.i("touchtest", "action_down " + activePointer.toString() +
			// "(" + x + "," + y + ")");
			androidRenderer.touch(x, y, activePointer);
			break;
		case MotionEvent.ACTION_MOVE:
			// Log.i("touchtest", "action_move " + activePointer.toString() +
			// "(" + x + "," + y + ")");
			androidRenderer.move(x, y, activePointer);
			break;
		case MotionEvent.ACTION_UP:
		case MotionEvent.ACTION_POINTER_UP:
			// Log.i("touchtest", "action_up " + activePointer.toString() + "("
			// + x + "," + y + ")");
			androidRenderer.up(x, y, activePointer);
			break;
		}
	}
	return true;
}

[Josh]

More info here:

http://android-developers.blogspot.com/2010/06/making-sense-of-multitouch.html

 

I've decided to move on to PC graphics card compatibility testing and am not investing more time in this, for now. Sorry.

[gamecreator]

Thank you for spending time trying to fix this. As the lack of this feature breaks the most basic mechanic - running and jumping or moving/turning and attacking/shooting - I hope this will eventually be fixed, for most Android customers' sake.

[Admin]

http://developer.android.com/training/gestures/multi.html

 

Unlike the older getAction() method, getActionMasked() is designed to work with multiple pointers.

That might be the cause of the trouble I had. Layer on top of layer of bad design.

[Josh]

This will get fixed from 3.0 but I may need to pull in some outside expertise.

[Josh]

I posted here, but new users are moderated and Google appears to have abandon their own forum:

https://groups.google.com/forum/#!forum/android-developers

 

I posted another topic about three months back and I guess they haven't gotten around to approving me yet.

 

Ah, here is where the Android developers hang out:

http://www.anddev.org/post2256233.html#p2256233

 

I think I will get an answer there.

[Josh]

Oh wow, I just started reading the other posts. That board is totally overtaken by spam.

 

StackOverflow to the rescue:

http://stackoverflow.com/questions/19528046/android-multitouch-event-indexes

[beo6]

I haven't played with it yet. But as far as i read in the android documentation you should use

MotionEventCompat.getActionMasked(event)

for the action to work with multiple pointers and

MotionEventCompat.getActionIndex(event)

to get the pointer index for that action.

 

But i haven't played much with the NDK myself but it reads pretty clear. Not sure why you are bitshifting there.

[Josh]

Working off of this code now:

http://stackoverflow.com/questions/14201130/how-does-the-ontouch-event-behave

 

It appears that touch indexes are not persistent. In other words, when touch index zero is lifted, the touches "shift" to the left, and touch index 1 becomes touch index 0.

 

Motion events always indicate touch index 0, so I tried looping through from 0 to event.getPointerCount(), but I get a crash on getEventX():

   		 for (int i = 0; i < event.getPointerCount(); i++)
  		 {
  	         Log.i("touchtest", "begin_move ");
  	         pointerIndex=event.getPointerId(i);
               x = event.getX(pointerIndex);
               y = event.getY(pointerIndex);	        
               Log.i("touchtest", "action_move " + pointerIndex.toString() +
                    "(" + x + "," + y + ")");                                
               androidRenderer.move(x, y, pointerIndex);
  		 }

[Josh]

I believe I have the solution.

 

In AndroidActivity.java, replace onTouchEvent with this code:

    @Override
   public boolean onTouchEvent(MotionEvent event) {
       Integer action,pointerIndex,pointerId;
       Float x,y;

       action = event.getAction();
       pointerIndex = event.getActionIndex();//(action & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT; //index of this pointer        
       x = event.getX(pointerIndex);
       y = event.getY(pointerIndex);
       pointerId = event.getPointerId(pointerIndex);

       switch (action & MotionEvent.ACTION_MASK){
       case MotionEvent.ACTION_DOWN:
       case MotionEvent.ACTION_POINTER_DOWN:
           // Log.i("touchtest", "action_down " + pointerId.toString() +
           // "(" + x + "," + y + ")");
           androidRenderer.touch(x, y, pointerId);
           break;
       case MotionEvent.ACTION_MOVE:
  		 for (int i = 0; i < event.getPointerCount(); i++)
  		 {
  	         Log.i("touchtest", "begin_move ");
  	         pointerId=event.getPointerId(i);
               x = event.getX(i);
               y = event.getY(i);	        
               //Log.i("touchtest", "action_move " + pointerId.toString() +
               //     "(" + x + "," + y + ")");                                
               androidRenderer.move(x, y, pointerIndex);
  		 }                
           break;
       case MotionEvent.ACTION_UP:
       case MotionEvent.ACTION_POINTER_UP:
           //Log.i("touchtest", "action_up " + pointerId.toString() + "("
           // + x + "," + y + ")");
           androidRenderer.up(x, y, pointerId);
           break;
       }
       return true;
   }

 

In main.cpp replace the Java_com_leadwerks_leandroidb_AndroidRenderer_move function with this code:

    JNIEXPORT void JNICALL Java_com_leadwerks_leandroidb_AndroidRenderer_move(JNIEnv * env, jobject obj, jfloat x, jfloat y, jint touchId)
   {
       if(touchId < 0) return;
       if (Leadwerks::Window::_TouchPosition[pointerIndex].x!=x || Leadwerks::Window::_TouchPosition[pointerIndex].y!=y)
       {
           Leadwerks3D::_TouchPosition[touchId].x = x;
           Leadwerks3D::_TouchPosition[touchId].y = y;
           Leadwerks3D::Event(EVENT_TOUCH_MOVE,NULL,touchId,x,y).Emit();
           //Leadwerks3D::Print("Move! "+Leadwerks3D::String(x)+", "+Leadwerks3D::String(y));
       }
   }

 

I will upload the fix now.

[Josh]

The fix is uploaded. I will leave this topic open for a day or two before closing it. Thanks for being patient.

[gamecreator]

Thank you. It looks like the touch detection is fixed but position issue isn't yet.

[Josh]

My tests indicated touch move events were working correctly. (I printed out the events and could see the numbers corresponding to my input.) Do you have a test that proves otherwise? Drawing some squares on the screen under the touch positions would be a good way to demonstrate it.

[gamecreator]

I use this code in my existing, updated project but I'll try creating a new project later and retest

 

context->DrawText("Touch down index 0: " + String(window->TouchDown(0)) + "  pos: " + window->GetTouchPosition(0).ToString(),5,100);
context->DrawText("Touch down index 1: " + String(window->TouchDown(1)) + "  pos: " + window->GetTouchPosition(1).ToString(),5,130);