code: public Matrix4f identity() {
          if ((properties & PROPERTY_IDENTITY) != 0)
              return this;
          MemUtil.INSTANCE.identity(this);
          this._properties(PROPERTY_IDENTITY | PROPERTY_AFFINE | PROPERTY_TRANSLATION | PROPERTY_ORTHONORMAL);
          return this;
      }
docs: Reset this matrix to the identity.
  <p>
  Please note that if a call to {@link #identity()} is immediately followed by a call to:
  {@link #translate(float, float, float) translate},
  {@link #rotate(float, float, float, float) rotate},
  {@link #scale(float, float, float) scale},
  {@link #perspective(float, float, float, float) perspective},
  {@link #frustum(float, float, float, float, float, float) frustum},
  {@link #ortho(float, float, float, float, float, float) ortho},
  {@link #ortho2D(float, float, float, float) ortho2D},
  {@link #lookAt(float, float, float, float, float, float, float, float, float) lookAt},
  {@link #lookAlong(float, float, float, float, float, float) lookAlong},
  or any of their overloads, then the call to {@link #identity()} can be omitted and the subsequent call replaced with:
  {@link #translation(float, float, float) translation},
  {@link #rotation(float, float, float, float) rotation},
  {@link #scaling(float, float, float) scaling},
  {@link #setPerspective(float, float, float, float) setPerspective},
  {@link #setFrustum(float, float, float, float, float, float) setFrustum},
  {@link #setOrtho(float, float, float, float, float, float) setOrtho},
  {@link #setOrtho2D(float, float, float, float) setOrtho2D},
  {@link #setLookAt(float, float, float, float, float, float, float, float, float) setLookAt},
  {@link #setLookAlong(float, float, float, float, float, float) setLookAlong},
  or any of their overloads.
  
  @return this