* Initialize and get the rendering for WebGL * @param canvas <cavnas> element * @param opt_debug flag to initialize the context for debugging *

* Create a program object and make current * @param gl GL context * @param vshader a vertex shader program (string) * @param fshader a fragment

* Create the linked program object * @param gl GL context * @param vshader a vertex shader program (string) * @param fshader a fragment shader p

* Checks the utils have been initialized.

* Gets an string version of an WebGL enum. * * Example: * var str = WebGLDebugUtil.glEnumToString(ctx.getError()); * * @param {number} val

* Create a shader object * @param gl GL context * @param type the type of the shader object to be created * @param source shader program (string