> For the complete documentation index, see [llms.txt](https://graygzou.gitbook.io/how-to/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://graygzou.gitbook.io/how-to/others/webgl/webgl_get_started.md).

# WebGL

## Basic facts

WebGL runs on the GPU on your computer. Vertex shader and a fragment shader and they are each written in a very strictly typed C/C++ like language called GLSL (GL Shader Language). Paired together they are called a program.

## Sending data

There are 4 ways a shader can receive data.

* Attributes and Buffers
* Uniforms : Data are passed to the shader that stay the same for all vertices in a draw call.
* Textures : Data from pixels/texels.
* Varyings : Data passed from the vertex shader and interpolated.

A Vertex shader which provides the clipspace coordinates and a fragment shader that provides the color. The majority of the WebGL API is about setting up state to supply data to our GLSL programs

## Rendering

In progress

## Keyswords

* attribute
* uniform
* precision medium
* varying

## Notes

* Clipspace coordinates always go from -1 to +1 no matter what size your canvas is
* Colors in WebGL go from 0 to 1.
* You should always set the size you want a canvas with CSS.

## Acknowledgements

Based on the following websites/blog posts :

* [webglfundamentals.org](https://webglfundamentals.org/webgl/lessons/webgl-fundamentals.html)