OpenGL ES Shading Language (ESSL)

The OpenGL ES Shading Language (ESSL) is the language we'll use to write our shaders. Its syntax and semantics are very similar to C/C++. However, it has types and built-in functions that make it easier to manipulate vectors and matrices. In this section, we will cover the basics of ESSL so that we can start using it right away.

GLSL and ESSL

It’s quite common for developers to refer to the shading language used in WebGL as GLSL. However, it is technically ESSL. WebGl2 is built on the OpenGL ES 3.0 spec and therefore uses ESSL, which is a subset of GLSL (the shading language for OpenGL).

This section summarizes the official GLSL ES specifications. You can find the complete reference at https://www.khronos.org/registry/OpenGL/specs/es/3.0/GLSL_ES_Specification_3.00.pdf.

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