anchor.diff:      (:max-texture-lod-bias :float 1)
       (:max-cube-map-texture-size :integer 1)
       (:max-renderbuffer-size :integer 1)
  +    ;; 6.62
       (:max-pixel-map-table :integer 1)
       (:max-name-stack-depth :integer 1)
       (:max-list-nesting :integer 1)
       (:max-eval-order :integer 1)
  -    (:max-viewport-dims :integer 2)
  +    (:max-viewport-dims :float 2)
  +    (:max-viewports :integer 1)
  +    (:viewport-subpixel-bits :integer 1)
  +    (:viewport-bounds-range :float 2)
  +    (:layer-provoking-vertex :enum 1)
  +    (:viewport-index-provoking-vertex :enum 1)
       (:max-attrib-stack-depth :integer 1)
       (:max-client-attrib-stack-depth :integer 1)
       (:aliased-point-size-range :float 2)
       (:point-size-range :float 2)
       (:point-size-granularity :float 1)
  -    (:smooth-point-size-range :float 2)
  +    ;; ?
  +    (:smooth-point-size-range :float 2) ;?
       (:smooth-point-size-granularity :float 1)
  -    (:aliased-line-width-range :float 2)
       (:line-width-range :float 2)
       (:line-width-granularity :float 1)
  +    ;; 6.63
  +    (:aliased-line-width-range :float 2)
       (:smooth-line-width-range :float 2)
       (:smooth-line-width-granularity :float 1)
  +    ;; get-convolution-parameter
       (:max-elements-indices :integer 1)
       (:max-elements-vertices :integer 1)
       (:compressed-texture-formats :enum :num-compressed-texture-formats)
       (:num-compressed-texture-formats :integer 1)
       (:max-texture-buffer-size :integer 1)
       (:max-rectangle-texture-size :integer 1)
  -    (:extensions :string 1)
  +    (:program-binary-formats :enum :num-program-binary-formats)
  +    (:num-program-binary-formats :integer 1)
  +    (:shader-binary-formats :enum :num-shader-binary-formats)
  +    (:num-shader-binary-formats :integer 1)
  +    (:shader-compiler :boolean 1)
  +    (:min-map-buffer-alignment :integer 1)
  +    ;; 6.64
  +    (:extensions :extensions/i 1 :num-extensions)
       (:num-extensions :integer 1)
       (:major-version :integer 1)
       (:minor-version :integer 1)
  
positive.code:     (:feedback-buffer-size :integer 1)
      (:feedback-buffer-type :enum 1)
      (:error :error 1)
      ;;
      (:alpha-test :boolean 1)
      (:auto-normal :boolean 1)
      (:blend :boolean 1)
      (:clip-plane0 :boolean 1)
      (:clip-plane1 :boolean 1)
      (:clip-plane2 :boolean 1)
      (:clip-plane3 :boolean 1)
      (:clip-plane4 :boolean 1)
      (:clip-plane5 :boolean 1)
      (:color-logic-op :boolean 1)
      (:color-table :boolean 1)
      (:convolution-1d :boolean 1)
      (:convolution-2d :boolean 1)
      (:cull-face :boolean 1)
      (:depth-test :boolean 1)
      (:dither :boolean 1)
      (:histogram :boolean 1)
      (:index-logic-op :boolean 1)
      (:light0 :boolean 1)
      (:light1 :boolean 1)
      (:light2 :boolean 1)
      (:light3 :boolean 1)
      (:light4 :boolean 1)
      (:light5 :boolean 1)
      (:light6 :boolean 1)
      (:light7 :boolean 1)
      (:line-smooth :boolean 1)
      (:line-stipple :boolean 1)
      (:minmax :boolean 1)
      (:point-smooth :boolean 1)
      (:polygon-offset-fill :boolean 1)
      (:polygon-offset-line :boolean 1)
      (:polygon-offset-point :boolean 1)
      (:polygon-smooth :boolean 1)
      (:polygon-stipple :boolean 1)
      (:post-color-matrix-color-table :boolean 1)
      (:post-convolution-color-table :boolean 1)
      (:scissor-test :boolean 1)
      (:separable-2d :boolean 1)
      (:stencil-test :boolean 1)
      (:texture-1d :boolean 1)
      (:texture-2d :boolean 1)
      (:texture-3d :boolean 1)
      (:texture-cube-map :boolean 1)
      (:texture-gen-q :boolean 1)
      (:texture-gen-r :boolean 1)
      (:texture-gen-s :boolean 1)
      (:texture-gen-t :boolean 1)
      ))
  
  ;;; Return the default array size for a state query enum.
  (defun query-enum-size (value)
  
negative.code:     (:stencil-back-fail :enum 1)
      (:stencil-back-pass-depth-fail :enum 1)
      (:stencil-back-pass-depth-pass :enum 1)
      (:depth-test :enable 1)
      (:depth-func :enum 1)
      ;; 6.30
      (:blend :enable/i 1 :max-draw-buffers)
      ;; ? (:blend-src :enum 1)
      (:blend-src-rgb :enum/i 1 :max-draw-buffers)
      (:blend-src-alpha :enum/i 1 :max-draw-buffers)
      ;; ? (:blend-dst :enum 1)
      (:blend-dst-rgb :enum/i 1 :max-draw-buffers)
      (:blend-dst-alpha :enum/i 1 :max-draw-buffers)
      (:blend-equation-rgb :enum/i 1 :max-draw-buffers)
      (:blend-equation-alpha :enum/i 1 :max-draw-buffers)
      (:blend-color :float 4)
      (:framebuffer-srgb :enable 1)
      (:dither :enable 1)
      (:index-logic-op :enable 1)
      (:color-logic-op :enable 1)
      (:logic-op-mode :enum 1)
      ;; 6.31
      (:index-writemask :integer 1)
      (:color-writemask :boolean/i 4 :max-draw-buffers)
      (:depth-writemask :boolean 1)
      (:stencil-writemask :integer 1)
      (:stencil-back-writemask :integer 1)
  