Problem with picking in 1.7.1

[kulesz]

Hi,

I'm new to Irrlicht (just a few days). I've managed to do some mesh rendering, terrain and mouse/keyboard input. Now I have a problem with mouse picking.
What I do is (skipped some texture code, camera and so on):

Init all the stuff

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device=createDevice( video::EDT_DIRECT3D9, dimension2d<u32>(SCREEN_W, SCREEN_H), 16, true, true, true, 0);
if (!(device))  return 1;
driver = device->getVideoDriver();
smgr = device->getSceneManager();
guienv = device->getGUIEnvironment();
device->setEventReceiver(&eventReciever);

Load mesh and add the node

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IAnimatedMesh* kobita_mesh = smgr->getMesh("media\\models\\kaplica.obj");
        IAnimatedMeshSceneNode* kobita_node = smgr->addAnimatedMeshSceneNode( kobita_mesh);

Set up the terrain

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scene::ITerrainSceneNode* terrain = smgr->addTerrainSceneNode(
                "MWM-CraterIsleHight.png",
                0,                                      // parent node
                -1,                                     // node id
                core::vector3df(0.f, 0.f, 0.f),         // position
                core::vector3df(0.f, 0.f, 0.f),         // rotation
                core::vector3df(60.f, 4.0f, 60.f),      // scale
                video::SColor ( 255, 255, 255, 255 ),   // vertexColor
                3,                                      // maxLOD
                scene::ETPS_17,                         // patchSize
                4                                      // smoothFactor
                );

Do some collision stuff

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ITriangleSelector* s = smgr->createOctreeTriangleSelector(kobita_mesh,
                                kobita_node, 32);
                kobita_node->setTriangleSelector(s);
                s->drop();

		scene::ISceneCollisionManager* collMan = smgr->getSceneCollisionManager();

And in render loop

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irr::scene::ISceneNode* selectedSceneNode = collMan->getSceneNodeFromScreenCoordinatesBB(irr::core::position2di(eventReciever.mouseX(),eventReciever.mouseX()), 0, false, 0);

x=selectedSceneNode->getPosition().X;
y=selectedSceneNode->getPosition().Y;
z=selectedSceneNode->getPosition().Z;

While I'm moving over the terrain and hovering mouse over the mesh, nothing happens. The x,y,z variables should show the node's position, but they don't. It works only sometimes, in a very close range to the node, but not always and only in certain positions/orientations. Also, x,y,x shows some random, 100+ numbers in certain areas of terrain.
Could anyone can help me with it? I can upload a full code, if someone have some time to look at.
Thanks in advance...

Kulesz

[Bate]

you used mouse X for x and y

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collMan->getSceneNodeFromScreenCoordinatesBB(irr::core::position2di(eventReciever.mouseX(),eventReciever.mouseX()), 0, false, 0);

try this:

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collMan->getSceneNodeFromScreenCoordinatesBB(device->getCursorControl()->getPosition(), 0, false, 0);

maybe that's already enough

[kulesz]

Thanks for quick reply... Tried your help, but it's still the same effect :-/
Tutorial example 7 compiles and works ok.

[blAaarg]

I don't know that this will solve your problem as your description of it seems like some other things may be going on. But if you're trying to find where on your node your mouse is hovering,

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getSceneNodeFromScreenCoordinatesBB()

will only get you the scene node itself, and it only has one position it can return: it's own. You may want to try

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getCollisionPoint()

or

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getSceneNodeAndCollisionPointFromRay()

[scarypajamas]

I don't know that this will solve your problem as your description of it seems like some other things may be going on.

I just wanted to say, I had the exact same problem as kulesz did. My code, WITHOUT ANY CHANGES, worked fine when I compiled and linked with irrlicht 1.6.1, but BROKE when I compiled and linked with irrlicht 1.7.1. So I'm not sure it's a problem with our code per-say, unless its a bug we are exploiting with irrlicht that was patched with 1.7.1...

In any case, I fixed the problem by ripping the following 2 functions from irrlicht 1.6.1 getSceneNodeAndCollisionPointFromRay and getPickedNodeBB in CSceneCollisionManager.cpp and pasted them over the new one's in 1.7.1