I'm facing issues to show shadows consistently for the 3D objects in the large scene.
In my case, objects would be added dynamically to the scene and the scene may grow larger and larger. When I have a single DirectionalLight for casting shadow it becomes blur. So I fixed an optimal settings for the DirectionalLight and thought to dynamically add more sources as and when it is required, so that shadow shows up consistently. Not sure if this is the correct approach, please correct me if I'm wrong.
So, I was experimenting to add a DirectionalLight to top, bottom, left and right of the current DirectionalLight source. I was able to add the DirectionalLight, however, intensity of the shadow become lighter as I add each DirectionalLight and after adding on the third side, shadow becomes invisible. Confused on how to proceed.
https://jsfiddle.net/arundhaj/6zL5tobk/
In the above experiment, you can find, I am getting consistent shadow with only two sources.
addShadowToBottom(shadowCameraPosition);
// addShadowToTop(shadowCameraPosition);
// addShadowToLeft(shadowCameraPosition);
// addShadowToRight(shadowCameraPosition);
shadow effect changes when uncommenting light on each side.
const shadowLight = new THREE.DirectionalLight(0xFFFFFF, 1);
If I change the intensity of light from 1 to 0.5, shadow shows up, however, it is very light and not as dark and crisp as it was at 1.
Is there any other approach to work on my scenario? Please let me know.
Related
I want to render a room with a floor + roof that is open to one side. The room contains a point light and the "outside" it lit by an ambient light (the sun). There is one additional requirement: The user should be able to look inside the room to see whats going on. But I cannot simply remove the roof because then the room is fully lit by the ambient light.
I think my problem could be solved by having 3d objects that are transparent by still are blocking the light.
To give you an idea about my current scene, this is how it looks like:
The grey thing is the wall of my room. The black thing is the floor of the room. The green thing is the ground of the scene. The room contains a point light.
I am currently using two scenes (see Exclude Area from Directional/Ambient Lighting) because I wanted the inside of the room to be unaffected by the ambient light. But now my lights can only affect either the inside of my room (the point light) OR the outside (the ambient light) but not both.
A runnable sample of my scene can be found here:
https://codesandbox.io/s/confident-worker-64kg7m?file=/src/index.js
Again: I think that my problem could be solved by having transparent objects that still block the light. If I had that I would simply have a 3d plane on top of my room (as the roof) and make it transparent... It would block the light that is inside of the (but still let it go outside if the room is open) and it would also block the ambient light (partially - if the room is open)...
Maybe there is also another solution that I am not seeing.
Just use one scene instead of two, then enable shadows across the relevant meshes so a light doesn't cross from inside to outside. Once you're using only one scene, the steps to take in your demo are:
Disable AmbientLight, and use DirectionalLight only, since AmbientLight illuminates everything indiscriminately, and that's not what you want.
Place the directional light above your structure, so it shines from the top-down.
Enable shadow-casting on the walls
Add a ceiling mesh with the material's side set to side: THREE.BackSide. This will only render the back side of the Mesh, which means it won't be visible from above, but it will still cast shadows.
const roomCeilMat = new MeshStandardMaterial({
side: BackSide
});
const roomCeiling = new Mesh(roomFloorGeo, roomCeilMat);
roomCeiling.position.set(0, 0, 1);
roomCeiling.castShadow = true;
scene1.add(roomCeiling);
See here for a working copy of your demo:
https://codesandbox.io/s/stupefied-williams-qd7jmi?file=/src/index.js
I would assign a flat, emissive material to the room. Or a depth gradient if it becomes terrain. Since ambient light doesn't cast shadow. It saves a light and extra geometry or groups. Plus web model viewer(s) would probably render it better. If you're doing a reveal transition, use a clip plane or texture alpha mask.
It depends on the presentation versus the output format. Also it depends on the complexity of the final floorplan. If your process is simple it will run Sims Lite on a Raspberry Voxel.
I'm looking for an way to give specify light for some objects.
I have added new light to object to remove shadow on it, but then, the other objects also affected by additional light, and I don't want it.
I have let the object's castShadow = false; receiveShadow = false, but it doesn't work.
When the camera is positioned with the light directions, camera will see the 'light' meshes, and at the opposite position, camera will see the dark side.
I want both sides to see 'light' meshes.
(I want to remove the shadow.)
Thanks for your help. :)
I have added new light to object to remove shadow on it, but then, the other objects also affected by additional light, and I don't want it.
What you are looking for is called "selective lighting" which is not yet supported by three.js. Check out the following issue for more information:
https://github.com/mrdoob/three.js/issues/5180
The only workaround right now is to work with multiple scenes and render passes.
When the camera is positioned with the light directions, camera will see the 'light' meshes, and at the opposite position, camera will see the dark side.
When using a single directional, point or spot light, it's normal that this setup produces a lit and unlit side of a sphere mesh. You can only avoid this by adding an additional light on the other side of the mesh, by using unlit materials or again by using different scenes with different lighting setups.
three.js R112
I need to get the camera up direction and i've tried many ways with no luck, i'm not an expert of quaternions so i'm doubting i did it right.
I've tried:
camera.up
camera.up.applyMatrix4(camera.matrixWorld);
new THREE.Vertex3(0,1,0).applyMatrix4(camera.matrixWorld);
camera.up.normalize().applyMatrix4(camera.matrixWorld);
after this i create two planes passing by two points of my interest, and add the plane helper to the scene and i can see they are very far from where i was expecting them. (i'm expecting two planes that looks like the top and bottom of the camera frustum).
P.s. the camera is a shadow camera of a directional light so an orthographic camera, and i manipulate the directional light position and target before doing this operation, but i've called updateMatrixWorld on the light, on it's target and the camera, on the camera i've called also updateProjectionMatrix... still no results
I've made a sandbox to see what i've tried till now, and better visualize what i want to achieve:
https://codesandbox.io/embed/throbbing-cache-j5yse
once i manage to get the green arrow to point to the top of the blue triangle of the camera helper i'm good to go
In the normal render flow, shadow camera matrices are updated as part of rendering the shadow map (WebGLShadowMap.render).
However, if you want the updated matrix values before the render, then you'll need to update them manually (you already understand this part).
The shadow camera is a property of (not a child of) the DirectionalLight. As such, it doesn't follow the same rules as other scene objects when it comes to updating its matrices (because it's not really a child of the scene). Instead, you need to call the shadow property's updateMatrices method (inherited from LightShadow.updateMatrices).
const dl = new THREE.DirectionalLight(0xffffff, 1)
dl.shadow.updateMatrices(dl) // <<------------------------ Updates the shadow camera
This updates the shadow camera with information from the DirectionalLight's own matrix, and its target's matrix, to properly orient the shadow camera.
Finally, it looks like you're trying to get the "world up" of the camera. Personally, I'd use the convenience function localToWorld:
let up = new THREE.Vector3(0, 1, 0)
dl.shadow.camera.localToWorld(up) // destructively converts "up" from local-to-camera into world coordinates
via trial and errors i've figured out that what gave me the correct result was:
calling
directionalLight.shadow.updateMatrices(...)
and then
new THREE.Vector3(0,1,0).applyQuaternion(directionalLight.shadow.camera.quaternion)
I'm trying to create a shadow in my orthographic scene in three.js. I'd like to have a directional light so the shadow is offset from all objects equally in the scene. I am however having problems using DirectionalLight.
My first problem is that I can't get the shado to cover the entire scene, only part of it ever has a shadow. I played with the light's frustum settings, but can't figure out how to get it to cover the scene. Ideally I'd want the frustrum to match that of the camera.
The second problem is that the shadows aren't "clean". If I use a SpotLight the shadows have nice crisp borders (but obviously not the universal directionality I want). When I use a DirectionalLight the borders are misshappen and blurry.
In the samples the tile is a simply box created with CubeGeometry.
How can I create an ortographic directional light source for my scene?
When I add to the scene two objects and set their transparency as true with some opacity and using TrackballControls I rotate the scene by mouse, the object which was initially further from camera loses its transparency.
I read that this is Z-buffer problem and further objects from camera will be displayed first. But when I rotate the scene using TrackballControls, camera changes its position, so transparent objects should be displayed correctly. But it is not like that.
Here in this picture - on the right is frontview, on the left is backview which is not displayed correctly:
http://www.foto-ondruskova.cz/Experiment/lenses.jpg
Please, any solutions?
I have come across this problem and setting alphaTest: 0.5 to the material as suggested here solved my problem. But it is hit and miss. Give it a try. Hopefully it works!