when ever I set camera.position anything other than (0,0,0) my rotation with pointer lock controls is all over the place. The whole scene goes crazy.
It seems to work if I change the position of yawObject and not camera.
So I guess that is ok,
How can i change the default rotation of pointer lock controls - I want to start by looking to the right.
Thanks.
controls.getObject().position.set( x, y, z);
Related
I am using Mr Doob's periodic table code in my web app:
https://threejs.org/examples/css3d_periodictable.html
I am using it in Helix view. When I rotate the object left, I shift the camera's Y position by a certain amount too. My desire is to give the impression that the Helix is corkscrewing vertically up and down as you rotate the camera. This is the code I'm using, where angle and panAmount are constants that control how much rotation and vertical pan takes place per second:
let g_RotationMatrix = new THREE.Matrix4();
g_RotationMatrix.makeRotationY(angle);
// Apply matrix like this to rotate the camera.
self.object.position.applyMatrix4(g_RotationMatrix);
// Shift it vertically too.
self.object.position.y += panAmount;
// Make camera look at the target.
self.object.lookAt(self.target);
The problem I'm having is that from the camera's perspective, the object appears to tilt towards you and away from you respectively, depending on the rotation direction, as the camera shifts vertically. This makes sense to me because the I'm guessing that the lookat() function causes the camera to look at the center of the target, and not at point on the target that is closest point to it, so the camera has to tilt to focus on the targe's center of mass. I see the same effect when I use the mouse to pan vertically using the Orbit controls. I believe another way to describe the effect is that the object appears to pitch up and down as the camera shifts vertically.
The effect I want instead is that of a window washer on an automated lift being raised up and down the side of building, with the side of the building appearing perfectly flat to the camera regardless of the camera's current Y position.
How can I achieve this effect with the camera?
Make the camera lookAt the target, but at the same y level as the camera.
Assuming self.target is a vector3 object and self.object is the camera:
If, for example, self.target is the camera's rotation center of the object, you wouldn't want to change the actual self.target vector. Make a copy of it first.
const newTarget = new THREE.Vector3( );
function render( ){
// copy the target vector to newTarget so that the original self.target
// will not change and the camera can still rotate around the original
// target.
newTarget.copy( self.target );
// Set newTarget's Y from the camera Y. So that is looks horizontal.
newTarget.y = self.object.position.y;
// Make the camera look at the objects newTarget
self.object.lookAt( newTarget);
}
I am using ThreeJS's OrbitControls so that when an object in my scene is clicked, the camera travels close to it and and starts orbiting around it. I'm just moving the controls.target position, camera position and setting controls.autoRotate = true.
The clicked object gets centered on screen, which is nice, but sometimes I need to show a text covering up to 50% of the bottom area of the screen, and then the selected objects gets hidden by it. So, I'd need to somehow offset the rotation center up a bit.
Perhaps another way of asking this is that I need to change the center of rotation so that it is NOT the center of the screen (or the center of the renderer canvas)
I've tried moving the target up but, of course, then the camera doesn't orbit around the selected 3D object but around an empty space close to it. Any idea on how to proceed?
Many thanks!
I finally got the desired results following the comments in this other thread:
by using camera.setViewOffset
I need to be able to change rotation pivot without changing camera lookAt on THREE.TrackballControls no mater what I tried I could not succeed. Please give me a direction to solve this problem. What I am actually trying to achieve is Revit like mouse controls.
I was able to solve this problem by creating 2 3D objects named orbit and target, then add target and camera into orbit as child objects... camera always looks at target.position, mousemove on x axis rotates the orbit object around Z axis (hence target and camera rotates around the orbit) and mousemove on y axis rotates the camera arm (camera.position vector) around cameraSideways direction.
I have initialised a perspective camera at a position looking at the origin (0,0,0). Reading around the most common solution to this I've found is the one described here https://stackoverflow.com/a/27412386/1330719.
From my understanding of the project method is, I should get a vector where the x,y coordinates are between -1 and 1. This doesn't seem to be the case at all and I end up getting coordinates that are completely out of bounds.
Furthermore, if the original vector point is at (0,0,0) I seem to get (NaN, NaN) back. If my camera is looking at position (0,0,0) I expect the Vector3 (0,0,0) to return (width/2, height/2).
In case it is needed, this is how I'm initialising my camera:
this.camera = new THREE.PerspectiveCamera(90, window.innerWidth / window.innerHeight, 1, 10E5);
this.camera.position.set(0, 500, -500);
this.camera.lookAt(new THREE.Vector3(0,0,0));
this.camera.updateProjectionMatrix();
Does anyone have a reason why this might not be working? Or alternatively a recommended way of mapping a Vector3 point to the screen space given a camera?
A jsfiddle of what I mean:
https://jsfiddle.net/m78wjLyc/
You should also use camera.updateMatrixWorld(true) before projecting.
Usually this is done automatically by renderer, but you don't use any, so the camera.matrixWorld stays untouched after you change the position, and makes the camera project things as if it was at the world origin.
I'm working on a simple Three.js demo that uses OrbitControls.js.
I'd like to change the behavior of panning in OrbitControls. Currently, when you pan the camera, it moves the camera in a plane that is perpendicular to the viewing direction. I'd like to change it so that the camera stays a constant distance from the ground plane and moves parallel to it. Google Earth uses a similar control setup.
Edit: I should have mentioned this detail in the first place, but I'd also like the point where you click and start dragging to remain directly under the cursor throughout the entire drag. There needs to be that solid connection between the mouse movement and what the user expects to happen on the screen. Otherwise, it feels as though I'm 'slipping' when I try to move around the scene.
Can someone give me a high-level explanation of how this might be done (with or without OrbitControls.js)?
EDIT: OrbitControls now supports panning parallel to the "ground plane", and it is the default.
To pan parallel to screen-space (the legacy behavior), set:
controls.screenSpacePanning = true;
Also available is MapControls, which has an API similar to that of Google Earth.
three.js r.94
Some time ago I was working on exactly this issue, i.e. adaptation of OrbitControls.js to map navigation.
Here's the code of MapControls.js.
Here's the demo of the controls.
I figured it out. Here's the overview:
Store the mousedown event somewhere.
When the mouse moves, get the new mousedown event.
For each of those points, find the points on the plane where those clicks are located (You'll need to put the points into camera space, transform them into world space, then fire a ray from the camera through each point to find their intersections with the plane. This page explains the ray-plane intersection test).
Subtract the world-space start intersection point from the world-space end intersection point to get the offset.
Subtract that offset from the camera's target point and you're done!
In the case of OrbitControl.js, the camera always looks at the target point, and its position is relative to that point. So when you change the target, the camera moves with it. Since the target always lies on the plane, the camera moves parallel to that plane (as long as you're panning).
You should set your camera 'up' to z axe:
camera.up.set(0,0,1)
And then, the main problem with OrbitControl is its panUp() function. It should be fixed.
My pull request : https://github.com/mrdoob/three.js/pull/12727
y axe is relative to camera axes and should be relative to a fixed plan in the world. To define the expected y axe, make a 90° rotation of camera x axe, based on world z axe.
v.setFromMatrixColumn( objectMatrix, 0 ); // get X column of objectMatrix
v.applyAxisAngle( new THREE.Vector3( 0, 0, 1 ), Math.PI / 2 );
v.multiplyScalar( distance );
panOffset.add( v )
Enjoy!