I have a model in Blender 2.8 ( and 2.79 ) with a grass texture on a plane. It's a field. No matter what I set the metalness and roughness to, when viewing it in ThreeJS there's always a whitish sheen on the field when looking at it from certain angles according to the sun position.
I think setting the specular color to black would remove that sheen, but I'm guessing this isn't currently possible to do because ThreeJS StandardMaterial doesn't control specular color..
So, basically, is there anyway to control the specular color on a ThreeJS StandardMaterial?
Use an environment map? Or change the color of your directional light?
Related
I am new to three.js and I created a classic sphere, wrapped with a world color map & bump map and an alpha map for clouds, and directional sunlight. How can I now add an earth at night texture only on the shadow side of the globe? The globe is rotating, so I couldn't just create 2 half-spheres.
I tried adding this grayscale mask to the texture, but it is also visible in daytime. I then tried illuminating the map with a different light aimed at the dark side, but couldn't selectively target only one material. I didn't quite understand if I need to use "emissiveMap".
Could I shine a light through a semi-transparent map/mask from the center of the earth to make the cities visible, or is there some type of "black light" to only make selected color/map areas shine in the dark?
I don't need any glowing effects, I just want it to be visible. Will I have to create individual light points or learn to use fragment shaders?
I've been baking textures (and shadows) in Cinema4D, and exporting as GLTF to import into Three.js. However, I'd like to animate some of these objects. Is there an equivalent to baking textures for moving objects, or a best way to do this?
three.js (as of r125) supports three types of lighting that could be pre-baked in Blender:
Diffuse / Base Color (material.map)
Lightmap (material.lightMap)
Ambient Occlusion (material.aoMap)
Of these, only ambient occlusion is usually baked for dynamic objects. This represents the "soft shadows" in corners, holes, and insets that would receive less light from diffuse (widely spread) sources. Directional sources (like THREE.PointLight) can still modify the effect of .aoMap as the object moves: for example, shining a light into a dark corner could hide all ambient occlusion. So this method remains useful for dynamic objects, more so than baked diffuse textures and light maps.
If you need additional "hard shadows" that depend on the direction of the light, those would need to be computed at runtime in three.js.
Distortion, color replacement on glb (gltf) models. Blue changes to green, and yellow changes to orange.
v106 three.js
v97 GLTFLoader.js
You're using an environment map in your preview in blender. That env map has a dominant color that will affect the coloring of your model. To compare these references, you want to make sure you're using the same envmap in both blender and webgl. If you are only using lights in your threejs scene, you'll want to make sure they are colored to match.
Another thing that can affect the coloring is the gamma output settings in your THREE.Renderer, and textures.
You can go through a lot of heroics to get the outputs of both renderers to match. Read this: https://discourse.threejs.org/t/whats-this-about-gammafactor/4264
If you just want a quicker fix.. tweak your lighting/envmaps, or tweak the colors/intensity of the lights you have set up in your threejs scene.
If this behavior is something that has changed between versions of THREE.. it may be something to file a bug report on.
There are now gamma related settings on both the threejs renderer and textures.
If this isn't enough info, let me know and I may know someone else who can help set you straight :) Hi Don!
Old question but for the record what caused it for me was the vertex colors under Object Data Properties:
Deleting the Col fixed the texture colors.
i am trying to cast an shadow on an totally transparent plane in SceneKit on OSX. I am struggling with this problem since several hours and do not come to any solution.
My Purpose is to generate an Screenshot of several objects with an transparent background and just the shadow on an invisible Plane.
Do you have any suggestions for me how i can make this with apples SceneKit?
Do i have to program my own shader, can i make this work with shadermodifiers or can i use built in functionallity?
UPDATE:
I find an alternative solution for anyone who needs:
create a white plane under 3D model, note that the color of plane must be pure white.
set blend mode of plane's material to SCNBlendModeMultiply.
set light model of plane's material to SCNLightingModelLambert.
This works because any color multiply white color (1, ,1, 1) return itself And lambert light model will not take account of directional light, So the plane will always be background color which look like transparent. Another benefit of this solution is you don't need change light‘s shadow rendering mode.
For people who used to inspector of Xcode.
According to SceneKit: What's New.
First, add a plane under you model. Then prevent it from writing to colorBuffer.
Second, change your light model's shadow rendering mode to deferred. Notice that you must use light which can cast shadows.
Oily Guo, your solution works. Here the solution is in code:
Configuration of the light source:
light.shadowColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.4)
light.shadowMode = .deferred
And for the floor (ie. SCNFloor underneath your objects):
material.diffuse.contents = UIColor.white
material.colorBufferWriteMask = SCNColorMask(rawValue: 0)
I do not have an answer to your question, however I have a workaround:
Render your scene and keep the image in memory
Change all the materials in your object for pure black, no specular
Change the plane and the sky to a fully white material, lights to white
Render the scene to another image
On the second image, apply the CIColorInvertand CIMaskToAlpha Core Image filters
Using Core Image apply the Alpha Mask to the first render.
You'll get an image with a correct Alpha channel, and transparent shadows. You will need to tweak the materials and lights to get the results you want.
The shadow may become lighter on the edges, and the only way around that is rendering it as yet another image, and filling it with black after the Mask to Alpha step.
I'm trying to use CanvasRenderer (three.js) as a fallback for devices not supporting WebGL. Is there some comparison page with explanation what is different and cannot be used with CanvasRenderer?
I'm experiencing two main issues:
flat shading, lights are completely missing (is MeshPhongMaterial supported?), I don't see any lighting nor shadows (are shadows supported in CanvasRenderer)? All I see is the diffuse texture without any lighting. In WebGL my current setup is PointLight, DirectionalLight, softShadows, antialiasing and MeshPhongMaterial (with diffuse, bump, spec and env map)
this.materialM = new THREE.MeshPhongMaterial({
ambient : 0x050505,
color : this.model.color,
specular : 0xcccccc,
shininess : 100,
bumpScale : BUMP_SCALE,
reflectivity : REFLECTIVITY,
});
transparent polygon edges (I know it can be tweaked with material.overdraw = 0.5 yet it produces other artifacts (as it probably does only some scaling of polys along the normal?), but I can do with this one
Any help on 1. or some general overview of what is not possible in CanvasRenderer when comparing to WebGLRenderer is greatly appreciated!
three.js r68
CanvasRenderer has limitations.
MeshPhongMaterial is not supported in CanvasRenderer -- it falls back to MeshLambertMaterial.
MeshLambertMaterial is supported, but not when the material has a texture -- it falls back to MeshBasicMaterial. ( MeshBasicMaterial is rendered without regards to scene lights. )
Shadows are not supported.
material.overdraw = 0.5 is helpful in hiding polygon edges when the material is opaque. It may still leave artifacts if the material is transparent.
three.js r.68