light seems to be coming from different directions per objec

[ChrisC]

I have created a light like this

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    scene::ILightSceneNode* l = smgr->addLightSceneNode(0, core::vector3df(100.f,100.f,100.f),
                            video::SColorf(1.f, 1.f, 1.f, 1.0f), 600.0f);
    l->setLightType(video::ELT_POINT);
    smgr->setAmbientLight(video::SColorf(.4f, .4f, .4f, 1.0f));
 

When creating each object I do this

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        scene::IMesh* cylinderMesh = smgr->getGeometryCreator()->createCylinderMesh(
                size.X, /*radius*/   size.Y/2.f, /*length*/   64, // tesselation
                video::SColor(255, 255, 255, 255), /*color*/  true, /*closeTop*/  0.0f  /*oblique*/);        
        node = smgr->addMeshSceneNode(cylinderMesh,
                0, /*parent*/  -1, // id
                core::vector3df(0, 0, 0), /*position*/   core::vector3df(0, 0, 0), //rotation
                core::vector3df(1.f,1.f,1.f) /*scale*/);
        node->setMaterialTexture(0, driver->getTexture("./data/metal.jpg"));
        smgr->getMeshManipulator()->recalculateNormals(cylinderMesh);
        node->setMaterialFlag(video::EMF_NORMALIZE_NORMALS, true);
 

As the cylinders are being moved around the light direction stays consistent for a particular object, but it looks like different objects have light coming from different directions

I don't know if it makes a difference but I'm moving the nodes like this

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                bodypos = dBodyGetPosition(p->body);
                p->node->setPosition(core::vector3df(bodypos[0],bodypos[1],bodypos[2]));
                q = dBodyGetQuaternion(p->body);
 
                dReal w=q[0];
                x=q[1];
                y=q[2];
                z=q[3];
 
                sx = x*x;
                sy = y*y;
                sz = z*z;
                sw = w*w;
 
                rot.X = (atan2(2.0 * (x*w + y*z ),(-sx - sy + sz + sw)) * irr::core::RADTODEG);
                rot.Y = (asin(-2.0 * (x*z - y*w)) * irr::core::RADTODEG);
                rot.Z = (atan2(2.0 * (x*y + z*w),(sx - sy - sz + sw)) * irr::core::RADTODEG);
                if (p->shape==physObj::ShapeType::cylinder) rot.X+=90;
                p->node->setRotation(rot);
 

NB its not different shapes have different light directions but examples of the smae shape (ie cylinders)

any clues as to what I might be doing wrong would be gratefully received

[Mel]

Unless otherwise specified, the nodes are lit by the closest light by default.

[ChrisC]

there is only 1 light - additionally touching cylinders that are at different angles, often don't have constant shading

[REDDemon]

A screenshot?

[ChrisC]

I can throw the same 3d objects at libgdx and get nice shading so I'll probably just stick with that...

[CuteAlien]

Hm, ok. Thought if we had a screenshot we might see what's going on and give hints.

[ChrisC]

http://bedroomcoders.co.uk/tmp/2017-02- ... _scrot.png
I've changed to a loaded obj - notice the shading is at 90 degrees to some of the other objects, and also its not interpolated between vertexes as I'd expect and see with the same model in libgdx

I'm now loading the scene node like this

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        scene::IMesh* cylinderMesh = smgr->getMesh("data/drum.obj");
        node = smgr->addMeshSceneNode(cylinderMesh,
                0, /*parent*/  -1, // id
                core::vector3df(0, 0, 0), /*position*/   core::vector3df(0, 0, 0), //rotation
                core::vector3df(size.X,size.X,size.Y) /*scale*/);
        node->setDebugDataVisible(scene::EDS_NORMALS );
 

I wouldn't waste too much time on this, I'm getting much better visuals and roughly the same performance with libgdx...

[kornwaretm]

have you try recalculating normals?

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yourNode->getMaterial(0).setFlag(video::EMF_NORMALIZE_NORMALS, true);
 

or

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yourNode->setMaterialFlag(video::EMF_NORMALIZE_NORMALS, true);
 

[CuteAlien]

Hm, guess I'd have to code a test - can't really tell from the image (it's pretty hard as that stuff depends on the angle between light and normal and I don't even see the light here - somehwere to the left I guess). Also long thin triangles like those are somewhat tricky for per-vertex lighting (small regular triangles work best with that).

@kornwaretm: he did ;-) (code in first post)

[ChrisC]

have you try recalculating normals?

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yourNode->getMaterial(0).setFlag(video::EMF_NORMALIZE_NORMALS, true);
 

or

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yourNode->setMaterialFlag(video::EMF_NORMALIZE_NORMALS, true);
 

already tried that without change

[ChrisC]

Hm, guess I'd have to code a test - can't really tell from the image (it's pretty hard as that stuff depends on the angle between light and normal and I don't even see the light here - somehwere to the left I guess). Also long thin triangles like those are somewhat tricky for per-vertex lighting (small regular triangles work best with that).

PM me with your email, I can send you the code, its just irrlicht used as a visualisation for ode so there isn't massive amounts of code

Tried with irrlichts mesh builder and loaded OBJ with identical results, the per vertex lighting seem to work fine elsewhere with the same models...

[CuteAlien]

Which videodriver are you using in Irrlicht? And on which OS is this?

[ChrisC]

Void Linux, Intel HD5500

[CuteAlien]

Thanks. Still wondering which videodriver - I mean the EDT_.... thing like EDT_OPENGL you set on createDevice. Just checking if you maybe did just set a software driver.

[ChrisC]

video::EDT_OPENGL