99 lines
2.5 KiB
Markdown
99 lines
2.5 KiB
Markdown
# glsl-token-descope
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[](http://github.com/badges/stability-badges)
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"Descope" an array of GLSL tokens such that they can be safely inlined alongside
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within another shader without causing any global variable conflicts.
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Useful for modularising GLSL source files, e.g. as is done in
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[glslify](http://github.com/stackgl/glslify), but should be useful in other
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tools too.
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Written with WebGL's GLSL syntax in mind – all the same, pull requests to
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support other variants would be much appreciated :)
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## Usage
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[](https://nodei.co/npm/glsl-token-descope/)
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### `descope(tokens, [rename(name)])`
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Takes an array of GLSL `tokens` produced by
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[glsl-tokenizer](http://github.com/stackgl/glsl-tokenizer) and renames variables
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to avoid global conflicts by modifying their "data" property in-place.
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For example:
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``` javascript
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var tokenize = require('glsl-tokenizer/string')
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var descope = require('glsl-token-descope')
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var stringify = require('glsl-token-string')
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var src = `
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precision mediump float;
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uniform mat4 top1;
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uniform float top2;
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void main() {
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float x = 1.0;
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gl_FragColor = vec4(vec3(x), top2);
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}
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`.trim()
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var tokens = tokenize(src)
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console.log(stringify(descope(tokens)))
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```
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Which should rename `main`, `top1` and `top2` to result in this output:
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``` glsl
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precision mediump float;
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uniform mat4 top1_0;
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uniform float top2_1;
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void main_2() {
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float x = 1.0;
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gl_FragColor = vec4(vec3(x), top2_1);
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}
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```
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Optionally, you may pass in a custom `rename` function as `descope`'s second
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argument to choose how you rename your variables. For example, adding a custom
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`rename` function to the previous function:
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``` javascript
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descope(tokens, function(name) {
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return 'a_' + name
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})
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```
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Would result in the following shader:
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``` glsl
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precision mediump float;
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uniform mat4 a_top1;
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uniform float a_top2;
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void a_main() {
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float x = 1.0;
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gl_FragColor = vec4(vec3(x), a_top2);
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}
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```
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## See Also
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* [glslify](http://github.com/stackgl/glslify)
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* [glsl-token-scope](http://github.com/stackgl/glsl-token-scope)
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* [glsl-token-depth](http://github.com/stackgl/glsl-token-depth)
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* [glsl-token-properties](http://github.com/stackgl/glsl-token-properties)
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* [glsl-token-assignments](http://github.com/stackgl/glsl-token-assignments)
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* [glsl-token-string](http://github.com/stackgl/glsl-token-string)
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## License
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MIT. See [LICENSE.md](http://github.com/stackgl/glsl-token-descope/blob/master/LICENSE.md) for details.
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