I used three's SplineCurve3 to drive the locomotive dynamically, but I wanted to put a camera in the cab. At the same time, the position of the camera changes with the locomotive to achieve the actual effect of the locomotive. How to control the position of the camera on the curved path?
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Implementing a three.js webxr web app and trying to get the real-world compass orientation relative to the three.js scene so that I can place objects oriented to north in the AR. e.g. Place an arrow on the floor pointing north.
Webxr sets y rotation to zero relative to the initial launch orientation of the device. i.e. 0 rotation is forwards when you start the app rather than, say, north.
I can get the webxr camera rotation with:
var XRCameraDirectionVector = new THREE.Vector3();
xrCamera.getWorldDirection(XRCameraDirectionVector);
let XRCameraDirectionDegrees = THREE.MathUtils.radToDeg(XRCameraDirectionVector.x);
I can get the compass per this article.
I know that I could take the compass bearing at the time that the zero is first set and use that as an offset, but I want to keep taking readings from the compass to improve the accuracy as the user moves around, so that would be fiddly.
I'm sure I'm missing something obvious, but how do I find where north is within the scene, please? Thanks.
I am trying to do a navigation system like google cloud infrastructure like this:
google cloud infrastructure.
I want to do this using aframe rather than threejs. So I am now customising aframe orbit control by keven ngo:
aframe orbit control.
The problem is that, I succeeded in limiting the auto rotation in a certain angle, so as pan. But I have some following problem that I do not know how to do after searching every posiblities and tried my self:
how to achieve the same effect of bouncing back smoothly after reaching out the pan limit;
for some reason if I pan and after mouseup then when mouse moves, it still pans rather than rotate. Why is that?
how to make camera rotates slightly like in google's example(I modified the original library to rotate camera when mousemove rahter than mousedown)?
Below is the glitch link of my experiment:
aframe customized orbit control
what I customized(I notated my change with slashes and ADDITION text):
autorotates between set angle;
mouse click only pans; when mouse move, camera rotates and autorotate stops;
pan can be limited.
This is a long question, very appreciated if anyone can help!!
how to achieve the same effect of bouncing back smoothly after reaching out the pan limit?
One idea: on mouseup (ie release of pan mode), check if the camera target is outside of the camera's viewing frustrum. If so, calculate a new target position, say half way between current target position, and a point in line with the camera z axis( ie, the center of the screen). Then make an animation, that moves the camera target from current location, to new location.
for some reason if I pan and after mouseup then when mouse moves, it still pans rather than rotate. Why is that?
It seems that the navigation mode (panning, orbitting,or zooming), does not change on mouse up. Make a new (mouseup) listener, that forces orbit mode back to a default mode (orbit?).
how to make camera rotates slightly like in google's example(I modified the original library to rotate camera when mousemove rahter than mousedown)?
It looks like in the google example, orbit direction is determined by which side of center the cursor is in. Left side makes autorotate go clockwise, and right side counterclockwise. You will need to use the cursor component to detect this, and change the orbit direction accordingly.
Also, it appears that in the google version, orbitting is not determined by mousedown (ie dragging), but by cursor distance to center, and this is added to the auto rotate. It appears to be a buffer system, where distance to center initially creates a value to alter the auto orbit (by adding or subtracting to the orbit amount), but that value is a buffer, meaning that it degrades to 0 over time (each frame the value is reduced slowly to 0).
I'm using THREE.OrbitControls to dolly a THREE.OrthographicCamera. But, even thought the ortho camera renders correctly as repositioned, all that is updating on the orthographic camera is the 'zoom' property. Even after calling camera.updateProjectionMatrix(). Do I need to manually update the 'position' property of the camera based on the updated 'zoom' property? I want to display its position in my UI after dollying it.
(Note, this is a rewrite of my other question,THREE.js Orthographic camera position not updating after zoom with OrbitControl, in which I thought I was zooming with the OrbitControl but was actually dollying. Sorry about this).
Dollying in/out with an ortho cam would have an unnoticeable effect. With ortho cams there is no perception of proximity because it has no perspective. All objects appear the same in size regardless of distance from the lens because the projection rays are all parallel. The only difference you'd notice is when the objects get clipped because they're past the near or far plane.
So, the decision was made that scrolling with OrbitControls would change the zoom of the camera, narrowing in/out of the center.
If you want to force the camera to move further/closer of its focus point, you could just translate it back/forth in the z-axis with:
camera.translateZ(distance); A (-) distance would move it closer, and a (+) distance would move it further from its focus point.
I am developing a WebVR application using Three.js. In it I am trying to get the standing position relative to the room.
How can I use the VRStageParameters.sittingToStandingTransform matrix in Three.js to transform my camera from sitting to standing space?
First of all, sorry for my english
I have two 3d viewport, the first one for editing and the other for live render. The problem is i need to orbit again so they have same viewing angle. So is there any other way to do it more easily?
If you have both 3D viewports showing the camera view numpad 0 you can enable Lock Camera to View and both viewports will show the same movement. You can find the lock to view option in the View panel in the properties region N. You only need to lock the one viewport that you will be using to move around in.
As this will actually move the location of the camera, you may want to have a second camera to use for this and switch the active camera between your viewport and rendering camera in the scene properties.