anchor.diff:                  match renderAsset with
                   | FontAsset (_, font) ->
                   
  -                    // construct sdl color
  -                    let mutable colorSdl = SDL.SDL_Color ()
  -                    colorSdl.r <- color.R8
  -                    colorSdl.g <- color.G8
  -                    colorSdl.b <- color.B8
  -                    colorSdl.a <- color.A8
  -
  +                    // 
                       // NOTE: the resource implications (throughput and fragmentation?) of creating and destroying a
                       // texture one or more times a frame must be understood!
                       let (offset, textSurface) =
  +                        let mutable colorSdl = SDL.SDL_Color ()
  +                        colorSdl.r <- color.R8
  +                        colorSdl.g <- color.G8
  +                        colorSdl.b <- color.B8
  +                        colorSdl.a <- color.A8
                           match justification with
                           | Unjustified wrapped ->
                               let textSurface =
  
positive.code:             let position = perimeter.Position.V2 * Constants.Render.VirtualScalar2
              let size = perimeter.Size.V2 * Constants.Render.VirtualScalar2
              let viewport = GlRenderer2d.computeViewport renderer
              let viewAbsolute = GlRenderer2d.computeViewAbsolute eyePosition eyeSize eyeMargin
              let viewRelative = GlRenderer2d.computeViewRelative eyePosition eyeSize eyeMargin
              let projection = GlRenderer2d.computeProjection viewport renderer
              let viewProjection = if absolute then viewAbsolute * projection else viewRelative * projection
              let font = AssetTag.generalize font
  
negative.code:             // begin frame
              let viewport = GlRenderer2d.computeViewport renderer
              let projection = GlRenderer2d.computeProjection viewport renderer
              let viewProjectionAbsolute = GlRenderer2d.computeViewAbsolute eyePosition eyeSize eyeMargin renderer * projection
              let viewProjectionRelative = GlRenderer2d.computeViewRelative eyePosition eyeSize eyeMargin renderer * projection
              OpenGL.Hl.BeginFrame viewport
              OpenGL.SpriteBatch.BeginFrame (&viewProjectionAbsolute, &viewProjectionRelative, renderer.RenderSpriteBatchEnv)
              OpenGL.Hl.Assert ()
  