Bootcamp3D ppt feb 21

Advanced 3D Techniques with WPF : Advanced 3D Techniques with WPF David Teitlebaum - Program Manager Jordan Parker - Developer Microsoft Corporation

Talk Outline : Talk Outline Introduction to WPF3D What do you need to do to see something? Interactive 2D on 3D Make VisualBrush work like you expected it to Performance Tips Learn how to avoid common mistakes

Jordan Parker : Jordan Parker basics

The Name Game Warmup Time : The Name Game Warmup Time Pattern: FooBar is a Bar with a Foo Examples: ModelVisual3D is a Visual3D with a Model3D GeometryModel3D is a Model3D with a Geometry3D MeshGeometry3D is a Geometry3D with a mesh ScaleTransform3D is a Transform3D with a scale And so on (generally) DrawingImage vs. ImageDrawing, anyone?

The Minimal Scene : The Minimal Scene Let’s do a simple 3D video example step-by-step

Our Coordinate System : Our Coordinate System Right-handed Notice that +Y is up… opposite of 2D! (Image from http://www.willamette.edu/~gorr/)

MeshGeometry3D : MeshGeometry3D Specifies a mesh of triangles Positions: Triangle vertices TriangleIndices: Optional indices into collections. Used to avoid duplicating vertices. Normals: Per-vertex orientation used in lighting. Generated for you if unspecified. TextureCoordinates: Describes the 2D Brush mapping. NOT generated for you. Not needed for SolidColorBrushes. Triangle vertices should be given in CCW order

TriangleIndices : TriangleIndices If specified: positions[indices[0]] positions[indices[1]] positions[indices[2]]… texcoords[indices[0]] texcoords[indices[1]] texcoords[indices[2]]… normals[indices[0]] normals[indices[1]] normals[indices[2]]… If not specified: positions[0] positions[1] positions[2] … texcoords[0] texcoords[1] texcoords[2] … normals[0] normals[1] normals[1] …

TextureCoordinates : TextureCoordinates (image from blogs.msdn.com/danlehen)

Normals : Normals If you don’t specify normals, we generate them by averaging the “true” surface normals of the triangles that share the vertex. This gives a smooth appearance. If you duplicate a vertex, it will end up with a different normal each time. Triangle specification matters! If you specify too many, we throw out the extras If you specify too few, we generate the rest

NormalsCylinder Cap Duplication Example : NormalsCylinder Cap Duplication Example

Positions: Specifying a Plane : Positions: Specifying a Plane (-1,1,0) 0 (0,0) (-1,-1,0) 1 (0,1) (1,-1,0) 2 (1,1) (1,1,0) 3 (1,0) Key: pos idx tc Looking down -Z, making a 2 x 2 plane on Z = 0

Mesh XAML : Mesh XAML We’ll let WPF compute the normals In general, you’ll be exporting a mesh to XAML from a tool or generating the mesh algorithmically

Materials : Materials Reflection/absorption of light EmissiveMaterial: Surface appears to give off light SpecularMaterial: Shine DiffuseMaterial: Soft scattering Takes a Brush for the base color Combine them with MaterialGroup When in doubt, use DiffuseMaterial

Material Examples : Material Examples

Video DiffuseMaterial XAML : Video DiffuseMaterial XAML

GeometryModel3D : GeometryModel3D Combines the Material and the Geometry3D Allows you to specify a transform (the plane mesh) (the video material)

Lights : Lights Not unlike reality, without light you can’t see anything* AmbientLight: Equal contribution everywhere DirectionalLight: The sun PointLight: Light bulb SpotLight: Self explanatory ? Lights are Model3Ds and thus have transforms We’ll use an AmbientLight in our example for simplicity * Except EmissiveMaterials

Model3DGroup : Model3DGroup (the ambient light) (the plane GeometryModel3D) Group multiple Model3Ds together Is itself a Model3D

Visual3D : Visual3D 3D analog of the 2D Visual class You need at least one just like you need at least one Visual in 2D (FrameworkElements are Visuals) To draw a Model3D, use ModelVisual3D (the Model3DGroup)

Cameras : Cameras Determine what part of the scene you see and project 3D onto a 2D plane OrthographicCamera: parallel lines stay parallel PerspectiveCamera: perspective foreshortening MatrixCamera: Specify your own projection

Viewport3D : Viewport3D The bridge from the 2D -> 3D It is a FrameworkElement Takes a Camera and the root of your Visual3D tree (the PerspectiveCamera) (the ModelVisual3D)

3D Video : 3D Video demo

Slide 24 : Interactivity

3.0: How Do I Know If I Selected a Mesh? : 3.0: How Do I Know If I Selected a Mesh? Issue a hit test on mouse move/click on the Viewport3D public void HitTest(object sender, System.Windows.Input.MouseButtonEventArgs args) { Point mouseposition = args.GetPosition(myViewport); PointHitTestParameters pointparams = new PointHitTestParameters(mouseposition); VisualTreeHelper.HitTest(myViewport, null, HTResult, pointparams); } public HitTestResultBehavior HTResult(System.Windows.Media.HitTestResult rawresult) { RayHitTestResult rayResult = rawresult as RayHitTestResult; if (rayResult != null) { RayMeshGeometry3DHitTestResult rayMeshResult = rayResult as RayMeshGeometry3DHitTestResult; if (rayMeshResult != null) { // HIT!!!! } } return HitTestResultBehavior.Continue; }

New in 3.5: UIElement3D : New in 3.5: UIElement3D Has everything you know and love from UIElement Derives from Visual3D Temporary concrete implementations: ContainerUIElement3D: only a collection of Visual3Ds ModelUIElement3D: only a Model property

3.5: Interactive 2D on 3D : 3.5: Interactive 2D on 3D Viewport2DVisual3D Bridge from 3D -> 2D Funny name, we know, but it mostly makes sense Three important properties: Visual: The Visual to be interactive on Geometry Material: The appearance of Geometry Set “IsVisualHostMaterial” attached property to “true” on the Material you want Visual to appear on. The Brush property will ignored on that Material. Geometry: The 3D geometry Note: Geometry and Material are separated (no Model3D) Perf tip: RenderOptions caching properties work on this

Our Scene Before : Our Scene Before ModelVisual3D DiffuseMaterial MeshGeometry3D GeometryModel3D VisualBrush “Media Panel”

Now with Interactive 2D on 3D : Now with Interactive 2D on 3D Viewport2DVisual3D DiffuseMaterial MeshGeometry3D “Media Panel” IsVisualHostMaterial = “true”

Interactive 2D on 3D Video : Interactive 2D on 3D Video demo

David Teitlebaum : David Teitlebaum performance

WPF3D PerformanceDo more with less : WPF3D PerformanceDo more with less Performance must be a priority throughout app construction Test early, test often Do not assume you can easily fix performance problems after your application is functionally complete Test on the hardware you care about Old Desktops, New Desktops, Laptops Most Dev machines are not “Old Desktops”

Potential Bottlenecks : Potential Bottlenecks CPU Easy to measure with task manager, profilers, etc. Many potential causes of CPU load GPU Hard to measure – there are few public tools to measure GPU load Can degrade frame rates without taxing CPU Few potential causes – typically the result of insufficient fill rate on the GPU or background video decode GPUs are optimized for video games with few state changes

WPF Hardware TiersKnow your limits : WPF Hardware TiersKnow your limits Coarse indicator of maximum machine capabilities Queryable via: (RenderCapability.Tier >> 16) Tier resides in the high word so don’t forget the shift! Indicates static capabilities An upper bound on what can be expected Does not account for dynamically consumed machine resources Value is read only (unfortunately! ?)

WPF Hardware Tiers Continued : WPF Hardware Tiers Continued

Useful Performance Tools : Useful Performance Tools Performance tools WPFPerf.exe Profilers Microsoft F1 AMD Code Analyst Intel Vtune

WPFPerf : WPFPerf demo

Best Practices Common Pitfalls : Best Practices Common Pitfalls #1 Brush Selection Persistence vs. Nonpersistence of realizations Intermediate Render Targets Texture memory swizzling Texture size Smaller is better Watch out for automatic texture sizing RenderTargetBitmap - best of both worlds?

Best Practices Common Pitfalls : Best Practices Common Pitfalls #1 Continued - RenderTargetBitmap Rectangle r = new Rectangle(); r.Width = 50; r.Height = 50; r.Fill = new LinearGradientBrush(Colors.CornflowerBlue, Colors.PeachPuff, 13.37); r.Measure(new Size(50, 50)); r.Arrange(new Rect(new Size(50, 50))); r.UpdateLayout(); RenderTargetBitmap rtb = new RenderTargetBitmap((int)r.ActualWidth, (int)r.ActualHeight, 96.0, 96.0, PixelFormats.Pbgra32); rtb.Render(r);

Best Practices Common Pitfalls : Best Practices Common Pitfalls #1 Continued - Brush Speed on Tier-2 Hardware in 3D ONLY

Best Practices Common Pitfalls : Best Practices Common Pitfalls #2 Disable Viewport3D.ClipToBounds WPF uses complex antialised clipping When Viewport3D.ClipToBounds == False, 3D content can exceed 2D region of Viewport3D Implementation of clipping is slow enough that it should be disabled when it is not needed

Best Practices Common Pitfalls : Best Practices Common Pitfalls #3 Disable Viewport3D.IsHitTestVisible WPF3D performs mouse-over hit testing on the CPU Mouse cursor is projected into object space and intersected with GeometryModel3D’s axis-aligned bounding box If bounding box is intersected, ray of projected mouse cursor must be intersection-tested against every triangle in GeometryModel3D, all on the CPU If you don’t need hit testing, disable it.

Best Practices Common Pitfalls : Best Practices Common Pitfalls #4 GeometryModel3D Coalescence Each Model3D requires a change of GPU state Each requires the projection of its axis-aligned bounding box to device coordinates A few complex GeometryModel3Ds is vastly preferable to many simple GeometryModel3Ds

Performance Impact of Model Coalescence : Performance Impact of Model Coalescence demo

Best Practices Common Pitfalls : Best Practices Common Pitfalls #5 Minimize Mesh Animations They do not scale well due to platform architecture Entire Collections are remarshalled rather than collection deltas Disconnect meshes from 3D scene before modifying to minimize change notifications Keep animated meshes small (a few thousand vertices at the most)

Best Practices Common Pitfalls : Best Practices Common Pitfalls #6 Disable 3D Antialiasing On Vista, WPF3D will try to render with 4 samples/pixel multisampling On XP, WPF3D will not try to multisample To prevent WPF3D from attempting to render with multisampling on Vista, add the attached property RenderOptions.EdgeMode=“Aliased” to your Viewport3D

Best Practices Common Pitfalls : Best Practices Common Pitfalls #7 Text in 3D Text is expensive Glyphs are abstractly defined by Beziers Glyphs are generated and cached according to scale Small glyphs – Bitmaps / Large glyphs - Polygons scale changes cause glyph cache invalidation, glyph regeneration, and glyph cache repopulation RenderTargetBitmap / ImageBrush is strongly recommended for static text

Best Practices Common Pitfalls : Best Practices Common Pitfalls #8 Caching of VisualBrush and DrawingBrush Attached Property - RenderOptions.CachingHint Use when ImageBrush is not sufficient Still slower than ImageBrush due to less aggressive texture memory swizzling on D3D’s RenderTargetTextures Frequency of cache regeneration can be controlled by RenderOptions.CacheInvalidationThresholdMinimum and RenderOptions.CacheInvalidationThresholdMaximum

Best PracticesCommon Pitfalls : Best PracticesCommon Pitfalls #9 BitmapEffects Should only be used on static 3D content Implemented on the CPU Forces affected content to also be rendered on the CPU Great for static content, otherwise don’t use them

Performance Impact of BitmapEffects : Performance Impact of BitmapEffects demo

Resources : Resources WPF3D http://blogs.msdn.com/wpf3d http://blogs.msdn.com/danlehen http://blogs.msdn.com/wpfsdk/archive/2007/01/15/maximizing-wpf-3d-performance-on-tier-2-hardware.aspx http://www.codeplex.com/3dtools WPF Perf http://blogs.msdn.com/timothyc http://blogs.msdn.com/kiranku Ask Questions http://forums.microsoft.com/MSDN/ShowForum.aspx?ForumID=119 news://microsoft.public.windows.developer.winfx.avalon Books Windows Presentation Foundation Unleashed by Nathan 3D Programming for Windows by Petzold

Slide 52 : © 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.