Three.js - Place a dynamic 2D Canvas on a PlaneGeometry - javascript

so I have a school project where I have to remake a GameBoy. For this I wanted to create a GameBoy model with ThreeJS (i'm a beginner) and use a public repo of a GameBoy emulator in JavaScript. So I somewhat finished the GameBoy model (still need some some stuff to be added but i'll make it better later) and I decided to use this repo for the GameBoy emulator https://github.com/alexaladren/jsgameboy. This repo worked perfectly fine when it was given a canvas with an ID "display". But when I tried to change the canvas to the canvas I made in ThreeJS it doesn't display anything, here is the code of when I make the Canvas:
geometry = new THREE.PlaneGeometry( 0.55, 0.45, 0.1 );
for (let index = 0; index < 6; index++) {
let x2 = document.createElement("canvas");
let xc2 = x2.getContext("2d");
x2.width = 320;
x2.height = 288;
xc2.fillStyle = "rgba(0, 0, 200, 0.5)";
x2.style.id = 'display';
screenCanvas = x2;
xc2.fillRect(0, 0, x2.width, x2.height);
let tex2 = new THREE.CanvasTexture(x2);
screen.push(new THREE.MeshBasicMaterial({
map: tex2,
transparent:true,
opacity:0.3
}))
number++;
}
material = new THREE.MeshBasicMaterial({color: 0xA1A935});
mesh = new THREE.Mesh( geometry, screen );
mesh.position.y = 0.25;
mesh.position.z = 0.3;
group.add(mesh);
Here is the code I edited in the emulator where the default "display" canvas was mentioned:
if(window.gb != undefined){
clearInterval(gb.interval);
screenCanvas.getContext("2d").setTransform(1,0,0,1,0,0);
}
gb = new GameBoy(arraybuffer);
gb.displaycanvas = screenCanvas.getContext("2d");
screenCanvas.getContext("2d").scale(2,2);
The PlaneGeometry is correctly displayed (I also tried BoxGeometry but same results) but the game won't display on the Canvas I created.
My thoughts on why it doesn't work:
- Because the Canvas is created in ThreeJS it doesn't seem to be added to the DOM elements and probably to the already existing ThreeJS canvas?
- Maybe the canvas I created isn't updating? But I set it to a CanvasTexture so it should update?
Thank you for your help.
Update: Still looking into it but haven’t found a solution, been trying to find help in 3 different Discord servers that provide threejs Discord but no luck. I might have to make the gameboy static while the game is playing and put the game display ontop of the screen if I don’t find another solution.

Related

Repair normals on possibly bad .stl files

I am new to Three.js and have been assigned the task of trying to repair the normals on files that have been coming in occasionally that appear to be bad. We do not know if they are bad scans or possibly bad uploads. We are looking into the upload function, but also would like to try and repair them if possible. Can anyone provide any ideas or tips to repair the file or find the correct normals?
Below is the code where we grab the normals and how we grab them. NOTE: this code works fine generally, it is only a problem when the normals are bad. I am also attaching one of the files so you can see the types of normals and "bad file" I am dealing with. Get File here
We are also using VTK on the backend with C++, so a solution or idea using either of these is helpful.
my.geometry = geometry;
var front = new THREE.MeshPhongMaterial(
{color: 0xe2e4dc, shininess: 50, side: THREE.DoubleSide});
var mesh = [new THREE.Mesh(geometry, front)];
my.scene.add(mesh[0]);
my.objects.push(mesh[0]);
var rc = new THREE.Raycaster();
var modelData = {'objects': [mesh[0].id], 'id': mesh[0].id};
var normalFound = false;
for (var dy = 80; dy >= -80; dy = dy - 10) {
console.log('finding a normal on', 0, dy, -200);
rc.set(new THREE.Vector3(0, dy, -200), new THREE.Vector3(0, 0, 1));
var hit = rc.intersectObjects([mesh[0]]);
if (hit.length) {
my.normal = hit[0].face.normal.normalize();
console.log('normal', my.normal.z);
modelData['normal'] = my.normal;
if ((my.normal.z > 0.9 && my.normal.z < 1.1)) {
my.requireOrienteering = true;
modelData['arch'] = 'lower';
normalFound = true;
console.log('we have a lower arch');
} else if ((my.normal.z < -0.9 && my.normal.z > -1.1)) {
modelData['arch'] = 'upper';
normalFound = true;
console.log('we have an upper arch');
}
break;
}
}
Calculating the normals is an easy step. If you calculate the cross product of two vectors (geometrical one), you will get a vector, that is orthogonal to the two, you input. All you have to do now is normalize it, since normals should be normalised to not mess up lightning calculations.
For smooth surfaces, you have to calculate all normals on the point and average them. For flat surfaces each vertex has multiple normales (one for each surface).
In pseudo code it will look like this for quads:
foreach quad : mesh
foreach vertex : quad
vector1 = neighborVertex.pos - vertex.pos;
vector2 = otherNeighborVertex.pos - vertex.pos;
vertex.normal = normalize(cross(vector1, vector2));
end foreach;
end foreach;
VTK has a filter named vtkPolyDataNormals that you can run on your file to compute normals. You probably want to call ConsistencyOn(), NonManifoldTraversalOn(), and AutoOrientNormalsOn() before running it.
If you want point-normals (instead of per-cell normals) and your shape has sharp corners, you probably want to provide a feature angle with SetFeatureAngle() and call SplittingOn().

Create very soft shadows in three.js?

is it possible to create a very soft / very subtle shadow in three.js?
like on this pic?
everything I managed to do so far is this:
My Lights:
hemisphereLight = new THREE.HemisphereLight(0xaaaaaa,0x000000, 0.9);
ambientLight = new THREE.AmbientLight(0xdc8874, 0.5);
shadowLight = new THREE.DirectionalLight(0xffffff, 1);
shadowLight.position.set(5, 20, -5);
shadowLight.castShadow = true;
shadowLight.shadowCameraVisible = true;
shadowLight.shadowDarkness = 0.5;
shadowLight.shadow.camera.left = -500;
shadowLight.shadow.camera.right = 500;
shadowLight.shadow.camera.top = 500;
shadowLight.shadow.camera.bottom = -500;
shadowLight.shadow.camera.near = 1;
shadowLight.shadow.camera.far = 1000;
shadowLight.shadowCameraVisible = true;
shadowLight.shadow.mapSize.width = 4096; // default is 512
shadowLight.shadow.mapSize.height = 4096; // default is 512
and render:
renderer.shadowMapEnabled = true;
renderer.shadowMapSoft = true;
renderer.shadowMapType = THREE.PCFSoftShadowMap;
thanks you
You can soften shadows by setting radius like this:
var light = new THREE.PointLight(0xffffff, 0.2);
light.castShadow = true;
light.shadow.radius = 8;
I was curious about this too, so i played around with all possible vars i found. The first real change made this one at init:
shadowLight.shadow.mapSize.width = 2048; // You have there 4K no need to go over 2K
shadowLight.shadow.mapSize.height = 2048; // - || -
Then i tested something other and when i've set:
shadowLight = new THREE.DirectionalLight(0xffffff(COLOR), 1.75(NEAR should in this case under 2), 1000 (FAR should just be the range between light/floor)); the Shadows smothing more out when i set also my directional lights position the 250 with:
shadowLight.position.set( 100(X just for some side effects), 250(Y over the scene), 0(Z) );
!!!!!!!!!!!!!!!!!Delete the (VAR) parts before using!!!!!!!!!!
Then i change this value to the value of my floor width.
d = 1000;
shadowLight.shadow.camera.left = -d;
shadowLight.shadow.camera.right = d;
shadowLight.shadow.camera.top = d;
shadowLight.shadow.camera.bottom = -d;
because if you use this:
var helper = new THREE.CameraHelper( shadowLight.shadow.camera );
and put it also in render:
scenes.add( shadowLight, helper );
...you see the box of your light and it should be maxed to your scene width itself i think. Hope it helps someone out.
What you're looking at is called Ambient Occlusion. There are a few things already available to look at, and you can probably find more now that you know what to search for. For example: Ambient occlusion in threejs
Actually that is not Ambient Occlusion. AO is only the contact shadow between 2 meshes which are very close one to each other.
What you are looking for, those soft shadows, you can get them in 2 ways:
First one, the easier: creating lightmaps in the 3D software that you use to create your models. That is: baking the shadows (and ambient occlusion too, if you want, and even textures and materials) into 1 texture that you can use later in ThreeJS. BUT: you will not be able to move those objects later... or better said, you will be able to move them, but their shadows will remain in the objects where they were being projected when you baked the lightmap.
The other way is doing something as it is done in this example, but unfortunately I haven't been able to go through it yet and I don't know much about it:
http://helloracer.com/webgl/
Good luck with it! Regards.
EDIT: Sorry... the 2nd option, the one with the F1 car, is still a lightmap :( But that shadow is made to follow the car, so the effect is quite nice at the end. Here you have the shadow being used, it is all baked, not real-time calculated:
http://helloracer.com/webgl/obj/textures/Shadow.jpg
I think drei is a good solution of soft shadow
https://github.com/pmndrs/drei#softshadows

Updating Terrain Geometry with Three.js

I'm experimenting with Bjørn Sandvik's really great process for importing terrain data into a scene.
Check it out:
http://blog.thematicmapping.org/2013/10/terrain-building-with-threejs.html
var terrainLoader = new THREE.TerrainLoader();
terrainLoader.load('../assets/jotunheimen.bin', function(data) {
var geometry = new THREE.PlaneGeometry(60, 60, 199, 199);
for (var i = 0, l = geometry.vertices.length; i < l; i++) {
geometry.vertices[i].z = data[i] / 65535 * 10;
}
var material = new THREE.MeshPhongMaterial({
color: 0xdddddd,
wireframe: true
});
var plane = new THREE.Mesh(geometry, material);
scene.add(plane);
});
My intent is to use this to display elevation data from a time series, so multiple .bin files will be loaded to provide data representing a period of several years to show change over time.
I am having difficulties updating the geometry with new data. I think that my difficulties stem from the plane and geometry variables being defined inside of a function, meaning that they are undefined in the global context. So later when I call those variables they don't have any value associated with them.
Does anyone have an idea of how I can update this geometry with new data loaded using the TerrainLoader?
anything you .add() to the scene object is visible as an element of the scene.children array -- to you can still reference your plane and the geometry of it as plane.geometry -- the the plane is the only object in the scene, it will probably be scene.children[0].geometry
See this page: https://github.com/mrdoob/three.js/wiki/Updates for hints on how to let THREE know the geometry is changing

three.js transparent png texture strange border webgl

I am having a strange problem when using pngs as a texture in three.js. The pngs get strange borders at the area between visible and transparent. I allready tried to play around with alphatest value but then sometimes the image disapears completly in areas where are really thin 1px lines. Is there a solution how to solve this?
var explosionTexture = new THREE.ImageUtils.loadTexture( 'explosion.png' );
boomer = new TextureAnimator( explosionTexture, 4, 4, 16, 55 ); // texture, #horiz, #vert, #total, duration.
var explosionMaterial = new THREE.MeshBasicMaterial( { map: explosionTexture } );
explosionMaterial.transparent = true;
var cube2Geometry = new THREE.PlaneGeometry( 64, 64, 1, 1 );
cube2 = new THREE.Mesh( cube2Geometry, explosionMaterial );
cube2.position.set(100,26,0);
scene.add(cube2);
// renderer
//renderer = new THREE.WebGLRenderer( { antialias: false, premultipliedAlpha: true } );
renderer = new THREE.WebGLRenderer( { antialias: false } );
Just try this:
explosionTexture.anisotropy = 0;
explosionTexture.magFilter = THREE.NearestFilter;
explosionTexture.minFilter = THREE.NearestFilter;
Also you should not use antialaising when constructing the renderer:
renderer = new THREE.WebGLRenderer({antialias: false});
Did this to preview minecraft texture packs, works great :-)
Use material blending, the following configuration worked for me:
material.blending = THREE.CustomBlending
material.blendSrc = THREE.OneFactor
material.blendDst = THREE.OneMinusSrcAlphaFactor
See this example:
http://threejs.org/examples/#webgl_materials_blending_custom
Congratulations, you've run directly into the Texel-to-Pixel-mapping-trap. :)
This should help you out of there, although it's not WebGL the basics still apply.
Ok, so I tried all the solutions on this page. They all failed.
What worked for me was to use the correct Texture.wrapS (horizontal wrapping) and Texture.wrapT (vertical wrapping) for the sprite texture.
I personally was finding this ugly edge on the top of my sprite. I just had to make sure my Texture.wrapT setting was THREE.ClampToEdgeWrapping instead of THREE.RepeatWrapping.
Solved the issue perfectly without messing with alpha test values, texture filters, vertices or antialiasing.
i solved it like this:
var c2GVertices = cube2Geometry.vertices;
for (var i = 0; i < c2GVertices.length; i++) {
c2GVertices[i].x = c2GVertices[i].x - 0.5;
c2GVertices[i].y = c2GVertices[i].y - 0.5;
}
is there an easier way to move all vertices a half pixel?

Three.js - Shape disappears on flip side

I've made a circle as follows:
material = new THREE.MeshBasicMaterial({ color: 0x00ff00 });
arcShape = new THREE.Shape();
arcShape.absarc( 0, 0, 20, 0, -Math.PI*2, true );
geometry = arcShape.makeGeometry();
circle = new THREE.Mesh(geometry, material);
scene.add(circle);
Like that, it is visible. But rotate it, and it disappears.
shadow.rotation.x = Math.PI / 2;
I've seen several other posts where this problem has not been solved. (So unless someone has a solution, I'll resort to making a flat cylinder instead. It's just a niggling problem).
I've set mesh.doubleSided = true and mesh.flipSided = false. I've also tried all 4 combinations of toggling the renderer's depthTest and the material's depthWrite properties.
Is there anything else I could try? If not, I'm guessing the code is sensitive to the order of some of my calls, in which case, I've had a long day so I'll stick with the cylinder!!
material.side = THREE.DoubleSide;

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