Server and Client Based Rendering

The second distinction to make is whether the rendering process is happening locally or remotely. When the image that needs to be rendered is too complex, the render will most likely occur remotely. This is the case for 3D animated movies where dedicated servers with lots of hardware resources render intricate scenes. We call this server-based rendering. The opposite of this approach takes place when rendering occurs locally. We call this client-based rendering. WebGL offers a client-based rendering approach: the elements that are a part of the 3D scene are usually downloaded from a server. However, the processing required to obtain an image is all performed locally using the client's graphics hardware. Although this is not a unique solution, compared to other technologies (such as Java 3D, Flash, and the Unity Web Player Plugin), WebGL presents several advantages:

• JavaScript programming: JavaScript is a language that is natural to both web developers and browsers. Working with JavaScript allows you to access all parts of the DOM and easily integrate WebGL applications with other JavaScript libraries such as jQuery, React, and Angular.
• Automatic memory management: WebGL—unlike other technologies, such as OpenGL, where memory allocation and deallocation are handled manually—follows the rules for JavaScript variable scoping and automatic memory management. This simplifies programming tremendously while reducing the code footprint. Ultimately, this simplification makes it easier to understand the application logic.
• Pervasiveness: Web browsers with JavaScript capabilities are installed in smartphones and tablet devices by default. This means you can leverage WebGL across a vast ecosystem of desktop and mobile devices.
• Performance: Performance of WebGL applications is comparable to equivalent standalone applications (with some exceptions). This is possible due to WebGL's ability to access the local graphics hardware. Until recently, many 3D web rendering technologies used software-based rendering.
• Zero compilation: WebGL is written in JavaScript; therefore, there is no need to compile your code before executing it on the web browser. This empowers you to make changes in real-time and see how those changes affect your 3D web application. Nevertheless, when we cover shader programs, we will understand that some compilation is needed. However, this occurs in your graphics hardware and not in your browser.