updated docs

Author: ojack

README.md

@@ -135,7 +135,7 @@ s0.clear()
 ```
 
 
-#### Non-global mode
+#### Non-global mode [in progress]
 If makeGlobal is set to false, buffers and functions can be accessed via the hydra instance. Note that sources and buffers are contained in an array and accessed by index. E.g.:
 ```
 hydra.s[0].initCam()
@@ -149,6 +149,13 @@ hydra.tick(dt)
 ```
 where dt is the time elapsed in milliseconds since the last update
 
+### Directly using shader code
+You can get access to the hydra shader code without rendering using hydra. For example,
+```
+osc().rotate().glsl()
+```
+returns a fragment shader string and list of uniforms. For vertex shader and attribute implentation, see https://github.com/ojack/hydra-synth/blob/master/src/output.js.
+
 #### Adding/editing transformation functions
 
 All of the available functions for transforming coordinates and color, as well as compositing textures, correspond directly to a snippet of fragment shader code. These transformations are defined in the file hydra/hydra-server/app/src/composable-glsl-transforms.js. When running locally, you can edit this file to change the available functions, and refresh the page to see changes.