activate method

void activate()

As you can have multiple Texture objects, but WebGL allways draws in the currently active one you have to call this function if you use more than one Textureobject before you can start rendering on it. If you forget it you will render into the wrong Texture.

Implementation

void activate() {
  FlutterAngle.activateTexture(this);
  FlutterAngle._rawOpenGl.glViewport(0, 0, options.width, options.height);
}