WebGL is an API for rendering graphics in web browsers, which is based on the functionality of the OpenGL ES graphics library. WebGLA JavaScript API that renders 2D and 3D graphics in a web browser. The Unity Web build option allows Unity to publish content as JavaScript programs which use HTML5 technologies and the WebGL rendering API to run Unity content in a web browser. More info
See in Glossary 2.0 (WebGL2) is the version of WebGL that Unity supports. WebGL2 almost matches with the OpenGL ES 3.0 functionality.
WebGL2 is widely accepted by most browsers and is the default Web graphics API in Unity.
There are best practice recommendations and restrictions for working with WebGL2:
By default, Unity Web clears the drawing buffer after each frame, which means the content of the frame buffer clears regardless of the Camera.clearFlags setting. However, you can change this behavior at instantiation time. To do this, set webglContextAttributes.preserveDrawingBuffer to true in the index.html file of your Web template.
Note : If you set any WebGL context attributes, you must also add a line to preserve the Power Preference Player setting.
script.onload = () => {
config['webglContextAttributes'] = {
preserveDrawingBuffer: true, //Add this line to preserve the Camera.clearFlags setting
powerPreference: {{{ WEBGL_POWER_PREFERENCE }}} //Add this line to preserve the Power Preference Player setting
};
createUnityInstance(canvas, config, (progress) => {
WebGL supports anti-aliasing on most (but not on all) combinations of browsers and GPUs. Anti-aliasing softens jagged edges in your sceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary.
To enable anti-aliasing:
Go to the Quality Settings (menu: Edit > Project Settings, then select the Quality category).
In the Rendering section, make sure Anti Aliasing isn’t set to Disabled.
For more information about anti-aliasing, refer to the Anti-aliasing documentation and Quality Settings.
The WebGL 2.0 specification imposes some limitations on OpenGL Shading Language (GLSL) shaderA program that runs on the GPU. More info
See in Glossary code. This is mainly relevant if you write your own shaders.
Precision qualifiers
WebGL 2.0 requires you to specify the precision of all variables in the shader. You can use highp, mediump, or lowp to specify the precision of the variable. If you don’t specify the precision, the shader will use the default precision, which is mediump. You can also use precision to specify the precision of a block of variables.
Unity Web supports dynamic font rendering similar to other Unity platforms. However, Unity Web doesn’t have access to the fonts installed on the user’s machine, so if you want to use any fonts, include them in the project folder (including any fallback fonts for international characters, or bold/italic versions of fonts), and set as fallback font names.
Unity Web only supports Baked Global Illumination. Realtime Global IlluminationA group of techniques that model both direct and indirect lighting to provide realistic lighting results.
See in Glossary isn’t currently supported in Web. Also, Unity Web supports non-directional lightmapsA pre-rendered texture that contains the effects of light sources on static objects in the scene. Lightmaps are overlaid on top of scene geometry to create the effect of lighting. More info
See in Glossary only.
You can’t use VideoClipImporter to import video clips to your Unity project because it might increase the initial asset data download size and prevent network streaming. To use video playback in Web:
URL option in the VideoPlayer component.StreamingAssets directory to use the built-in network streaming of your browser.Due to limited available memory in Web, don’t include unwanted shader variants because it can lead to unnecessary memory usage. Therefore, it’s recommended to familiarize yourself with shader variantsA verion of a shader program that Unity generates according to a specific combination of shader keywords and their status. A Shader object can contain multiple shader variants. More info
See in Glossary and shader stripping. Also, take extra care to ensure that you don’t add shaders with too many variants (for example, Unity’s Standard Shader) to the Always-included Shaders section in Graphics Settings.