WebGL is a Javascript API for rendering interactive 3D / 2D graphics on the HTML5 canvas element. It is based on OpenGL ES 2.0.

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162 views

How do I draw a multi-object mesh at once?

This is a very elementary question. At the moment I am drawing lots of faces separately by setting a location uniform separately for each one of them. This is very slow. As I understand it, the ...
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1answer
943 views

WebGL rendering performance and frustum culling

When I render five boxes in WebGL with one texture for all of them, the app runs at 60 FPS, nice. But when I render 70 boxes the performance decreases to ~40fps... but only 5 of the boxes are visible. ...
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1answer
217 views

Can you have shader variables that vary per primitive?

A shader normally has values that vary per-vertex and values that vary per-fragment. Can you have values that vary only per primitive, such as per-triangle or per-quad?
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1answer
49 views

Custom lookAt function goes wild

I have written a custom lookAt function based on a lot of posts from all over the net, and it works very nice... except when a rotation (which is stored in a quaternion) crosses some 'threshold'. ...
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1answer
158 views

How can I restrict the rotation of an object to a subset of axes using quaternions?

I've got a question about quaternions in my WebGL application. How can I rotate an object only around two axes? For example, how can I exclude/nullify rotation about the Y axis? The problem is that ...
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0answers
67 views

Textures occasionally rendering twice on a particular face [closed]

I am learning how to render 3D objects using webgl (no third-party libraries). I am currently facing a very confusing situation however, where my textures are rendering apparently twice over a ...
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0answers
88 views

Is there an out-of-the-box way to create a custom non-convex polygon in three.js?

Does Three.js offer an out-of-the-box way to create custom non-convex polygon, or do I have to use THREE.Geometry and set faces manually? I'm guessing that ShapeGeometry has something to do with this, ...
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0answers
391 views

shader-based particle systems

I have a classic particle system where each particle is represented by a quad and, each time step, I move each particle. My target is webGL which means I don't have instancing, attribute divisors nor ...
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2answers
4k views

Best physics engine for OpenGL ES (different implementations)? [closed]

Can you recommend a good physics engine which is easily portable between WebGL and other OpenGL ES implementations like in Android and iPhone? I don't want a game engine. Only the physics part.
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105 views

Why are some of my normals facing away from the camera?

I'm trying to use WebGL to render some simple models, and I'm running into issues where pixels near the edge of my model are passing normals to my fragment shader that point away from the camera. This ...
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2answers
77 views

Need to know the origin and coordinates for 2d texture and 2d/3d vertices in webgl

Long story short, I know my coordinates are off and I believe my indices might be off. I'm trying to render a simple 2d rectangle with a texture in webgl here's the code I have for the vbo/ibo: ...
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1answer
189 views

3d immersive Virtual Conference meeting environment development on the web (3d website)-Help required [closed]

I want to develop 3d immersive virtual collaborative conference meeting environment on the web i.e an immersive virtual environment for our university Teachers to attend and address conference ...
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1answer
61 views

Strange quaternion camera streching in WebGL

So after a lot of researching about quaternions I almost got the quaternion camera working. Almost, cause it rotates in a proper way only in a vertical axis. Other rotations stretches and deforms the ...
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1answer
42 views

(WebGL) Point light per-fragment issue

I'm using an FPS-like camera, this is the code: CAMERA mat4.identity(mat.mvMatrix); mat4.rotate(mat.mvMatrix,degToRad(-camera.pitch),[1,0,0]); ...
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1answer
94 views

First person camera world matrix issue (in THREE.js and webGL)

I'm trying to create a Portal-like effect in webGL using THREE.js. I have two scenes connected by a pair of portals. The view of the 2nd scene in rendered inside the 1st portal using stencils and ...
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1answer
37 views

How would one outline an alpha transparency layer in javscript and/or php? [duplicate]

I simply want an outline/edge detection of the character/item/object that is selected or doing something. I'm seeing lots of versions of this question for different languages, but I would appreciate ...
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1answer
251 views

best way of rendering more 3D models in three.js that not slow down page?

I am in the way of creating a 3D web game using threeJS library. This is a multi-player game that players are 3D human models in game, and I need to add a human 3D model for each player that enters ...
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1answer
776 views

How can I implement 3D textures using webgl?

I went through the google I/O video but did not get exactly how to do it. If somebody could point me to a simple 3D texture implementation using webgl, it would be helpful. i basically have a volume, ...
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3answers
1k views

How do I create menu with text in OpenGL?

How would I go about creating a menu system with fonts in OpenGL? I want to make a dungeon crawler and will need a menu for inventory and stats for the weapons. I can draw a world made out of blocks ...
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0answers
71 views

Custom rotateTowards function and rotating only around two axises

I'm building a framework for my WebGL project and at the moment I have a problem with a function which will rotate an object towards a target vector with a given angular speed. In Unity engine it's ...
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0answers
33 views

Is it possible or not to share a geometry among many meshes and applied a different shaderMaterial for each?

I instanciate one PlaneGeometry, then I instanciate 200 meshes sharing this geometry and with their own instance of a given shaderMaterial. Here is a simplified version of the code : ... var geom = ...
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0answers
30 views

Strauss model : no specular component [duplicate]

I implemented the Strauss model with the metalness, transparency and smoothness parameters, taking the formulas from the book "Programming vertex geometry and pixel shaders", this is how I implemented ...
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0answers
56 views

How can I compute spotlight attenuation when I only have a spotlight cutoff angle?

I am trying to compute the spot light attenuation, though I don't have a spotCosCutoff (cosine of the spotlight cutoff angle) predefined variable in the shader so I have to compute it myself. This is ...
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1answer
217 views

Having a problem with texturing vertices in WebGL, think parameters are off in the image?

I'm having a problem texturing a simple rectangle in my WebGL program, I have the parameters set as follows: gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, textureImage); I'm ...
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1answer
116 views

WebGL CORS error loading simple texture in Chrome

Here's my code: function loadTexture() { textureImage = new Image(); textureImage.onload = function() { setupTexture(); } textureImage.src = "jumper2.png"; } function ...
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0answers
57 views

Rotation of a car? [duplicate]

I am working on a game. I want to rotate enemies car so that they face the player car and move to approach it. I tried couples of techniques and algorithm but did not get fruitful results. I want to ...
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0answers
30 views

How do i draw a volume cube and fill it up with a 3D texture in webgl? [duplicate]

Possible Duplicate: How can I implement 3D textures using webgl? I have a set of (x-y) images of the cross-section of an object varying along the z-dimension. From that i have to construct ...
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1answer
715 views

How to draw a circle with WebGL using GL_POINTS [closed]

I'm trying to draw a circle using simple vertices points and a big gl_PointSize value. I found this example and try to reproduce it on WebGL with no success.
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2answers
192 views

enemy shooting towards FPS [closed]

WELL first of all I want you to see my game (its deployed on heroku cloud) : http://still-escarpment-3701.herokuapp.com (It takes almost 10 sec to load so please wait for couple of sec) I have ...
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1answer
435 views

How can I create a WebGL camera based on quaternions?

I am trying to create a WebGL camera based on quaternions. I looked at many tutorials, and none is as simple as it could be or it was not working. How can I create such a camera?