H3D.org - Forum

Re: Adding widget to a frame

Tue, 18 Jun 2013 08:07:40 +0200

Did you have a look at the UI toolkit? Comes with full H3D windows package or you can install the debian version on linux or build from source.
Together with the Billboard node and/or some code to calculate the window size you can get some ok code for this.

Re: Adding widget to a frame

Mon, 17 Jun 2013 18:45:53 +0200

A widget with haptic capabilities.

Re: HAPI and Phantom device

Mon, 17 Jun 2013 10:45:49 +0200

Hello,

The problem seems to be that OpenHapticsRenderer expects a normal for the LineSet. I have no idea however what kind of normal to return when the object to intersect with is a line. See the return values of OpenHapticsRenderer::intersectCallback and OpenHapticsRenderer::closestFeaturesCallback which are used for as functions for custom shape in OpenHaptics for HL_SHAPE_INTERSECT_LS and HL_SHAPE_CLOSEST_FEATURES. I would assume that the normal that is calculated and returned does not make any sense for OpenHaptics when it comes to magneticLine calculation. You are welcome to test solutions to this problem by modifying LineSegment::lineIntersect in CollisionObjects.cpp. (I also noticed that this function does not set "result.face" to something, which I assume it should. ) You could for example approximate the line with a small cylinder to get the normal or something like that, however that would also really be "wrong" for the actual function. A better solution would be to use the Cylinder primitive (as with sphere primitive) or perhaps write your own primitive.
The reason for even detecting a collision between two lines (which is what happens in the intersectCallback) is that OpenHaptics defines as input a line from some point in space (probably the proxy position) to the closest point on the object to collide with (calculated in closestFeaturesCallback).

RuspiniRenderer is the only implemented renderer for which lines and points can be felt. The only exception is "magneticSurface" for lines/points using OpenHapticsRenderer, but that is not really a surface, that is some kind of force effect masked as surface. To see an equivalent of this see the MagneticGeometryEffect of H3DAPI or the HapticShapeConstraint of HAPI. HAPIDemo demonstrates the HapticShapeConstraint. Perhaps this is actually all you need in the end, why did I not think of that earlier.

From H3DAPI a HapticLineSet is used. However, a custom shape is not used which basically means that OpenHapticsRenderer uses OpenGL to calculate the magnetic effect and not the HL_SHAPE_INTERSECT_LS and HL_SHAPE_CLOSEST_FEATURES callbacks. That is why it apparently works there.

Re: Adding widget to a frame

Mon, 17 Jun 2013 08:19:42 +0200

A widget with haptics capabilites or just graphics?

Re: paintable texture example

Mon, 17 Jun 2013 08:17:13 +0200

Use the CMake gui to generate a visual studio solution file.

1. In "Where is the source code" put the path to Whereveryouinstalledit/UsefulNodes/build.
2. In "Where to build the binaries" put the path to where you want the solution file to end up.
3. Press "Configure".
4. Press "Generate".
5. Open the solution file and remove the WebCameraTexture.cpp and GraspTransform.cpp node from the project since they seem to not work with the new release. I should probably upload a new version of UsefulNodes that compiles with latest release out of the box.
6. Right click on the INSTALL project and choose "build".

Re: HAPI and Phantom device

Fri, 14 Jun 2013 14:34:33 +0200

Ok maybe I was to fast to exult for success: I am at the second stage of the implementation now.

I succesfully created a magnetic sphere, but my original aim was to create a set of magnetic lines.

so I just replaced the sphere part with a HapticLineSet as in the following code snippet :


#ifdef SPHERE // works

  HapticPrimitive *my_haptic_sphere =  new HapticPrimitive( 

    new Collision::Sphere( Vec3( 0, 0, 0 ), 0.05 ), 

    my_surface, Collision::FRONT ); 



   hd->addShape( my_haptic_sphere ); 

#else   // doesn't 



   vector<Collision::LineSegment> lineSegments;



   lineSegments.push_back(Collision::LineSegment(Vec3(-0.05,0,0),Vec3(0.5,0,0)));



   HapticLineSet *lines = new HapticLineSet(lineSegments,my_surface,Collision::FRONT_AND_BACK);// tried with Collision::FRONT as well 



   // Add the shape to be rendered on the device. 

   hd->addShape( lines );

#endif

But I can only feel a friction effect where the lines are supposed to be, but no magnetic effect.

I read on the manual that "RuspiniRenderer is for example the only implemented renderer for which lines
and points can be felt" but on the other hand the magneticSurface in H3D works perfectly on my computer. So I guess there must be a way.

I have been delving in MagneticSurface.cpp and LineSet.cpp in H3D but it doesn't seem to me that HapticLineSet is used.

Adding widget to a frame

Fri, 14 Jun 2013 03:59:26 +0200

Hi

I need to add a widget at the bottom right corner of frame(a picture in picture display). Can someone please help me with this ? I am not able to find any examples describing how to add a widget to a frame.

Thank You

Re: paintable texture example

Fri, 14 Jun 2013 02:02:36 +0200

hi Markus,
i dont get how to do this, i open in visual studio 2010 paintableTexture.cpp(put in source) e the paintableTexture.h ( put in header) . But in header file say
cannot open this files, i dont know where are this library

#include
#include
#include

i would like to work with this example, but i dont know how to build it. I download the "useful nodes" file. I search in the site and dont find how to build the cpp nodes. I have to use the Cmake ? i dont know how to use it, i was tryed but dont get work.
thanks for helping me

Re: paintable texture example

Thu, 13 Jun 2013 07:53:57 +0200

Well, yes and no. The x3d/python is correct however you also need the PaintableTexture C++ node. It exists in UsefulNodes (downloadable from the downloads page). You need to download it, build it and then make sure that the file can find it (using ImportLibrary x3d node).

paintable texture example

Wed, 12 Jun 2013 22:04:37 +0200

Hello,
i have a problem with this example, i cant paint in the retangule. I used the novint and touch the retangule, press buttons and touch, but the example dont do nothing.
The only thing i have to create is two files the "paintabletexture.x3d" and the phyton "paintabletexture.py"?

paintabletexture.x3d

and the phyton file

paintabletexture.py

from H3DInterface import *

# This field class just takes the first value of its input MField
# and uses it as output
class FirstTouchTexCoord( TypedField( SFVec3f, MFVec3f ) ):
def update( self, event ):
tex_coords = event.getValue()
if( len(tex_coords) > 0 ):
return tex_coords[0]
else:
return Vec3f( 0, 0, 0 )

firstTexCoord = FirstTouchTexCoord()

Its correct ?

Thanks for helping me.

Re: HAPI and Phantom device

Wed, 12 Jun 2013 16:55:01 +0200

It works! I was running an old version of HAPI, after updating to the last release It did the job.

Thank you Markus

ps: I run windows

Re: Adding support for devices

Wed, 12 Jun 2013 09:27:41 +0200

So obviously I remembered wrong. In the upcoming release 2.0 of Candy, which I'm working on right now, the trackers have X3DChildNode as base. I just forgot that this had changed.

The reason it will be a major revision is because some nodes have been removed and other have changed their interfaces, so an upgrade might not be a simple switch. If you do not need the new filtering functionality, or any other new node, I'd recommend you to stay with the current release.

Re: Adding support for devices

Tue, 11 Jun 2013 20:56:34 +0200

Update:

I ended up modifying the HVRTrackerNode so that it implements X3DChildNode instead of X3DNode.

Re: HAPI and Phantom device

Tue, 11 Jun 2013 08:32:40 +0200

Weird, it works perfectly fine for me.
The proxy should be updated in OpenHapticsRenderer.cpp in a function called transferContactsAndProxy( void *data )

Until I change the second argument of "new OpenHapticsRenderer" to false the reported proxy position is garbage.

Just make sure that void OpenHapticsRenderer::initRenderer is called and that the transferContactsAndProxy callback is created. If it is then print out the value of the proxy in that thread.
If you want to make sure it is not some clash with OpenGL then compile HAPI without OpenGL support (remove the OpenGL library in CMake GUI.

What system are you using? Windows or linux?

Oh, and one more thing, in your example. Add another argument to OpenHapticsSurface if you did not already, and set the value to 10, or disable the magnetic property then move the omni around to feel the sphere.

Re: HAPI and Phantom device

Mon, 10 Jun 2013 19:14:11 +0200

thank you but it doesn't work. The proxy position is not updated, whereas wtih GodObjectRenderer it is.

It looks like it gets updated only if I call clearEffects(), addShape() and transferObjects() at every step of the while cycle.

Re: Adding support for devices

Mon, 10 Jun 2013 18:25:21 +0200

Quote:

karlu wrote:
If I remember correctly all tracker nodes are child nodes so you should be able to put the VRPNTracker node under any grouping node by manually setting container field to children.

VRPNTracker inherits from HVRTrackerNode, which is only an X3DNode. So if I do containerField="children" in the VRPNTracker, an error window pops up stating:


InvalidNodeType: VRPNTracker. Expecting class H3D::X3DChildNode

If I don't set the container field, I get the following error:


XMLParseError: Invalid containerField attribute "tracker". The field does not exist in parent node (Unnamed Group)

So it seems to me like I still have the same issue where I need some kind of node that contains a tracker to put my VRPNTracker node inside of.

Re: Impenetrable surface

Mon, 10 Jun 2013 10:13:28 +0200

Finally, set proxyWeighting to 1. Which basically means that the proxy should be rendered at the proxy position, this might fool some people into believing that the surface is "rigid".

For an Omni the best super-stiff-surface-trick is to calibrated it so the physical device reaches the physical table when you touch the virtual surface :P

Re: HAPI and Phantom device

Mon, 10 Jun 2013 10:09:23 +0200

Hello,
Try this:


hd -> setHapticsRenderer( new OpenHapticsRenderer(OpenHapticsRenderer::OpenHapticsOptions::CUSTOM, false) );

For some reason the use_adaptive_viewport have to be false. I wonder if I should change this default value or something.. hmm. Although changing default values probably not good practice.

Also when you use the magnetic surface remember to set the snap_distance to something good (the last parameter, which you did not provide in your example of the OpenHapticsSurface). It is given in mm so 10 works fine for me.

Re: CMake error (Mac)

Mon, 10 Jun 2013 09:47:35 +0200

Thanks for the reply.

They do have the same parent directory

/my_projects/h3d/H3DAPI
/my_projects/h3d/HAPI
/my_projects/h3d/H3DUtil

(and the HAPI has been built successfully)

Re: Impenetrable surface

Sat, 8 Jun 2013 15:36:28 +0200

You can also cheat by applying event-based haptic feedback, which will give a bit better feel even with an impedance control. It needs some advanced fine-tuning, however, such as device characterization and applying an inverse model transfer function. Check the literature for Kuchenbeckers work on event-based haptics in 2005.