I am using ThreeJS r67
I have a static room with lighting baked so lights do not need to affect it, but I also have a person in the room that does need the lighting. Is there a way to set all the materials in the room to ignore the lights?
According to the ColladaLoader.js (in three.js r67) lines 3550-3572 you can specify in the collada model file what type of material to create. You are probably using blinn or phong and you need to change that to constant.
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I’m having a hard time getting an aoMap working in three.js…
I have a glb asset with an aoMap on the red channel or something. When I bring it into to the babylon viewer, I can see the ao just fine, but it wont show up in the three.js viewer or my project. I think this has something to do with a second set of uvs, but I can't find a resource that involves doing that on top of using the gltf loader… I really don't know what to do here. Any response would be greatly appreciated!
Here is my code (I’m using a html-canvas as the texture)
And I get the model’s geometry and diffuse texture (all white) as desired, but the aomap isnt showing…
code
babylon viewer
three.js viewer
working application with shadows included in diffuse
not working, diffuse is just white, and aoMap is not showing
You're right about needing a second set of UVs. The reason behind this is that diffuse textures often repeat (think of a brick wall, or checkered t-shirt). AO shading, however, is more likely to be unique on each part of the geometry, so it's almost never repetitive. Since this often would need an alternative UV mapping method, the default is to use a second set of UVs.
You could do 2 things:
Re-export your GLTF asset with a duplicate set of UVs.
Duplicate existing UVs in Three.js by creating a new BufferAttribute in your geometry:
// Get existing `uv` data array
const uv1Array = mesh.geometry.getAttribute("uv").array;
// Use this array to create new attribute named `uv2`
mesh.geometry.setAttribute( 'uv2', new THREE.BufferAttribute( uv1Array, 2 ) );
.getAttribute and .setAttribute are methods of BufferGeometry, if you want to read more about them.
In Three.js I am looking closely at the glsl source for MeshPhongMaterial. I notice the fragment shader relies on a uniform named diffuse. However there does not appear to be any way to set it. There is also an uniform named color that can be set and does indeed alter what looks like the diffuse color. Huh?
Is color copied to diffuse under the hood somehow? Can someone untangle this mystery for me.
If you look or search though the source you'll find it's set based on the color of the material
For example here
MeshPhongMaterial is not a subclass of ShaderMaterial even though they both extend Material.
Internally WebGLRenderer keeps track of / knows how to deal with two different things:
Any ShaderMaterial with any uniform. This means that you can make an exact copy of MeshPhongMaterial using ShaderMaterial and instead of myMaterial.color you'd have myMaterial.uniforms.color.
"Built-in" materials and their properties. For these, WebGLRenderer is aware of all the possible properties these materials expose. Gman has pointed out where in the code this happens (one of the places). For each material WebGLRenderer internally creates a ShaderMaterial but instead of handling it's uniforms like it would with any other such material, it manually keeps track and updates everything.
The built-in materials make little sense, since you can easily pipe foo.bar to foo.uniforms.bar using getters and setters leaving the renderer to only deal with shader materials.
If you really really want a uniform created for a built in material, you have to wait until the renderer creates them, and you can tap into this process with material.onBeforeCompile = shader=>{} (the shader object will contain the uniforms).
Blender has the ability to set a material to Flat or Smooth.
In the Blender exporter for three.js, when I check "Export Normals" to JS model, I always export all materials as Smooth. The exported file is twice bigger.
Is there a way to export models with Flat Shaded and Smooth shaded faces without need to set it manually in three.js ?
There is no flatshading/noshading/smoothshading equivalent in blender. However as few other features (blending, depthwrite, depthtest) it could be proposed in the 'threejs' part of the material pannel.
You could do it yourself by editing the following files in the addon :
constants.py,
__init__.py,
exporter/material.py,
exporter/api/material.py
(copy the way blending types work for example)
You would just pay attention that the blender io-three addon yet has a shading field for materials, used to define phong or lambert materials. You would just have to chose an other name.
Finally you would also have to edit threejs so the JSONLoader can parse the new property you add.
That said, it is a bit longer than setting your materials properties in your code, since you will always need to write material=new THREE.Mesh****Material(properties)...
I'm currently working on something along the lines of a plugin for another program to add 3D capability to it, so I'm trying to put all the functionality i can from three.js into it, with the added goal of this being a good way to learn all the functionality of three.js firsthand.
I'm running into an issue now as i implement textures and materials that with mesh basic material, setting some things which the documentation on the main threejs.org site shows are features, doesn't actually do anything.
when i set a texture for either specularmap or lightmap nothing is actually showing up. Im pretty sure its not a mistake im making because setting the texture of the map works, but trying to set this same texture for the specularMap or lightMap is doing nothing. Does a regular texture work for these, or do i have to do something different?
I'd also like to know what the shading property does for mesh basic, because as far as i can see setting it to smoothshading/flatshading/noshading is doing nothing aswell.
MeshBasicMaterial does not respond to lights. Change your material to MeshLamberMaterial or MeshPhongMaterial, for example.
For MeshBasicMaterial and MeshLambertMaterial, the specularMap is used only to modulate the reflection when an environment map is used.
For any material, lightmaps require a second set of UVs. geometry.faceVertexUvs[ 0 ] contains the usual set of UVs; for a lightmap, you need to add geometry.faceVertexUvs[ 1 ], a second set of UVs.
For MeshBasicMaterial, the shading property only applies when an environment map is used. SmoothShading will yield smooth reflections; FlatShading will yield faceted reflections.
three.js r.66
I am trying to simulate the OpenGL flat shading model using Three.js. My idea is creating an example like http://en.wikipedia.org/wiki/File:Phong-shading-sample.jpg. I was trying to change some different shading models but I cannot obtain the desired result.
Is it possible to create this scene in three.js?
Thanks in advance
Materials e.g. the MeshBasicMaterial have an option called "shading". It can be set to THREE.None, THREE.FlatShading, THREE.SmoothShading.
I am not sure if you need a light source in the first place or wether you have to enable shading for a the whole scene. Look at the demos at the Three.js website for something with shading.