public void Apply(EffectPass pass)
        {
            Using(this);

            int passIndex = pass.Index;

            if (passIndex > 0)
            {
                EffectPass previusPass = _techniques[_currentTech][passIndex - 1];
                previusPass.Clear(this, _device);
            }

            pass.Apply(_currentTech, _device);
            _lastPass = passIndex;
        }
        public void Apply(int passIndex)
        {
            EffectPass pass = _techniques[_currentTech][passIndex];

            Apply(pass);
        }