init method

@override Future<void> init(RenderingContext gl, { Caps? caps, })

Create GL objects, compile shaders, cache uniform locations.

Implementation

@override
Future<void> init(RenderingContext gl, {Caps? caps}) async {
  // Intentionally don't await; draw() will early-return until ready.
  unawaited(_ensureProgram(gl));
  // Loads the skydome texture from a Flutter asset and prepares mipmaps.
  // The shader program is ensured (compiled/linked) in the background; drawing
  // safely no-ops until both the program and texture are available.

  _tex ??= gl.createTexture();

  gl
    ..bindTexture(WebGL.TEXTURE_2D, _tex)
    ..texParameteri(
      WebGL.TEXTURE_2D,
      WebGL.TEXTURE_WRAP_S,
      WebGL.CLAMP_TO_EDGE,
    )
    ..texParameteri(
      WebGL.TEXTURE_2D,
      WebGL.TEXTURE_WRAP_T,
      WebGL.CLAMP_TO_EDGE,
    )
    ..texParameteri(
      WebGL.TEXTURE_2D,
      WebGL.TEXTURE_MIN_FILTER,
      WebGL.LINEAR_MIPMAP_LINEAR,
    )
    ..texParameteri(WebGL.TEXTURE_2D, WebGL.TEXTURE_MAG_FILTER, WebGL.LINEAR)
    ..pixelStorei(WebGL.UNPACK_ALIGNMENT, 1);

  await gl.texImage2DfromAsset(
    WebGL.TEXTURE_2D,
    assetPath,
    internalformat: WebGL.RGBA,
    type: WebGL.UNSIGNED_BYTE,
  );

  gl.generateMipmap(WebGL.TEXTURE_2D);
}