gl-shader-extract

Extracts active uniforms and attributes from a compiled WebGLProgram at runtime and normalizes their types to match GLSL syntax.

For an offline version, see glsl-extract.

Example

var extract = require('gl-shader-extract')

var fragSource = 'void main()'
var vertSource = `
  attribute vec4 position;
  uniform mat4 projection;
  void main() { 
    gl_Position = projection * position;
  }
`

//compile the source into a WebGLProgram object
var program = ...

//get the uniforms and attributes
var data = extract(gl, program)

console.log(data.attributes[0]) 
// { type: "vec4", name: 'position' }

console.log(data.uniforms[0]) 
// { type: "mat4", name: 'projection' }

Usage

Install

npm install gl-shader-extract --save

API

data = extract(gl, program)

Extracts the type and name from each uniform/attribute that was active in the shader. The returned data looks like this:

{
  attributes: [ { name: 'position', type: 'vec4' } ],
  uniforms: [ { name: 'projection', type: 'mat4' } ]
}

uniforms = extract.uniforms(gl, program)

As above, but only extracts the uniforms array.

attributes = extract.attributes(gl, program)

As above, but only extracts the attributes array.

Type Mapping

|getProgramParameter|normalized| |---|---| | FLOAT_VEC2 | vec2 | | FLOAT_VEC3 | vec3 | | FLOAT_VEC4 | vec4 | | INT | int | | INT_VEC2 | ivec2 | | INT_VEC3 | ivec3 | | INT_VEC4 | ivec4 | | BOOL | bool | | BOOL_VEC2 | bvec2 | | BOOL_VEC3 | bvec3 | | BOOL_VEC4 | bvec4 | | FLOAT_MAT2 | mat2 | | FLOAT_MAT3 | mat3 | | FLOAT_MAT4 | mat4 | | SAMPLER_2D | sampler2D | | SAMPLER_CUBE | samplerCube |

WebGL 2.0 Support

The following are also translated in WebGL2.

|getProgramParameter|normalized| |---|---| | FLOAT_MAT2x3 | mat2x3 | | FLOAT_MAT2x4 | mat2x4 | | FLOAT_MAT3x2 | mat3x2 | | FLOAT_MAT3x4 | mat3x4 | | FLOAT_MAT4x2 | mat4x2 | | FLOAT_MAT4x3 | mat4x3 | | UNSIGNED_INT | uint | | UNSIGNED_INT_VEC2 | uvec2 | | UNSIGNED_INT_VEC3 | uvec3 | | UNSIGNED_INT_VEC4 | uvec4 | | UNSIGNED_INT_SAMPLER_2D | usampler2D | | UNSIGNED_INT_SAMPLER_3D | usampler3D | | UNSIGNED_INT_SAMPLER_2D_ARRAY | usampler2DArray | | UNSIGNED_INT_SAMPLER_CUBE | usamplerCube | | INT_SAMPLER_2D | isampler2D | | INT_SAMPLER_3D | isampler3D | | INT_SAMPLER_2D_ARRAY | isampler2DArray | | INT_SAMPLER_CUBE | isamplerCube |

Credits

This was pulled out from @mikolalysenko's gl-shader for use in other engines/frameworks.

License

MIT, see LICENSE.md for details.