The shader had the JS code 'window.__flightDir.dx' baked into the GLSL string, which GLSL can't parse. Added a uFlightDir uniform (vec2) and pass the dx/dz from JS via gl.uniform2f. Shader reads uFlightDir.x and uFlightDir.y.
The shader had the JS code 'window.__flightDir.dx' baked into the GLSL string, which GLSL can't parse. Added a uFlightDir uniform (vec2) and pass the dx/dz from JS via gl.uniform2f. Shader reads uFlightDir.x and uFlightDir.y.