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3D Modelling

3D Modelling. Week 3 Advanced modelling. Aims of today. Discuss your presentation Advanced modelling. Last week. Software Modelling concepts Polygon Spline Patch Parametric 3D parametric modelling Primitives Transformations Aligning Cloning Modifying primitives Boolean.

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3D Modelling

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  1. 3D Modelling Week 3 Advanced modelling

  2. Aims of today • Discuss your presentation • Advanced modelling 3D Modelling

  3. Last week • Software • Modelling concepts • Polygon • Spline • Patch • Parametric • 3D parametric modelling • Primitives • Transformations • Aligning • Cloning • Modifying primitives • Boolean 3D Modelling

  4. Plan your model • Massing model? • Use a graphic or scan? • Set up your grid • Set up a file/folder system 3D Modelling

  5. Sketch or Storyboard Adventure Gamers : Dreamfall: from sketch to 3D model (2005) 3D Modelling

  6. Accuracy • Imagine a pen • How would you model it? • Now look at a real pen • Details make a big difference • Practice to be imperfect • Why? 3D Modelling

  7. References • Using reference materials will improve the quality of your model • Build a reference library • The object itself • Photographs • Drawings • Video 3D Modelling

  8. 2D • One method of creating a complex 3D object • Convert the lines into 3D objects • Visualise and define cross-sections • Proper scale 3D Modelling

  9. 2D to 3D - Extrusion 3ds max v7 3D Modelling

  10. 2D to 3D - Lathing • Create a path • Choose an axis 3ds max v7 3D Modelling

  11. 2D to 3D – Sweep or Loft • Create a 2D shape • Create a path • Cap or close the ends? 3ds max v7 3D Modelling

  12. 2D to 3D - Skin • Create a number of cross-sections • Skin them 3ds max v7 3D Modelling

  13. Activity • Draw a 2D shape and extrude it • Create another 2D shape and lath it • Create a 2D shape, a path and create a loft • Find out how to do a skin 3D Modelling

  14. File formats for modelling • Portable or universal file format • DXF .dxf • Drawing Interchange Format • Widely used in CAD (Computer Aided Design) • OBJ .obj • Computer animation an visual effects • Native • May be converted • 3ds max .max 3D Modelling

  15. Exporting/importing files • File conversion • 3D Studio (3DS) • Adobe Illustrator (AI) • ASC Scene Export (ASE) • AutoCAD (DWG) • AutoCAD (DXF) • Shockwave 3D • FiLMBOX (FBX) • Initial Graphics Exchange Standard (IGES) • Lightscape Material (ATR) • Lightscape Blocks (BLK) • Lightscape Parameter (DF) • Lightscape Layers (LAY) • Lightscape View (VW) • Lightscape Preparation File (LP) • Stereolithography (STL) • VRML97 (WRL) 3D Modelling

  16. Edges • Real objects rarely have a sharp edge • Bevel or chamfer • Radius • Fillet 3ds max v7 3D Modelling

  17. Surface Modelling • More free form than geometric (parametric) modelling. • A subdivision surface is a surface that has been divided into more faces while retaining the object's general shape • Subdivision adds more detail to an object, or to smooth it out • Use modifier stack to “collapse” a parametric model to some form of editable surface. 3D Modelling

  18. Why surface modelling? • Great flexibility in modelling • Game engines expect a mesh • Default model type • During rendering polygons are ‘smoothed out’ • Meshes allow the optimisation of models • Reduce the number of faces • Low polygon modelling • Reduce rendering time • Key part of successful production 3D Modelling

  19. Mesh objects • Early versions of Max used triangles • All faces were coplanar • Good for the rendering engine • Over time rendering engines have been modified • Polygon modelling without subdivision • More efficient • Eliminated extra edges • More control over the polygon object 3D Modelling

  20. Meshes • Triangles • Vertex • Edge • Face • Polygons • Vertex • Edge • Border • Polygon • Element 3ds max v7 3D Modelling

  21. Mesh or poly - which to use? History lesson • Initially Max only supported mesh objects • Subdividing the mesh into triangular faces ensured that all faces were coplanar • Guaranteed to render well • Over time rendering engines have been modified to handle polygons • Makes the model more efficient • Eliminates all the extra edges required to triangulate the mesh Murdock K.L. (2005) 3D Modelling

  22. Tessellation • Subdivides the faces of the object into two or more: • Polygons or • Triangles 3ds max v7 3D Modelling

  23. Converting to editable objects • Use the Quad menu • Or • Right click the object in the Modifier Stack 3ds max v7 3D Modelling

  24. Editing a polygon model • Convert an object into a editable polygon • Removes all parametric controls, including the creation parameters • If a modifier has been applied to an object you need to use the Collapse All command first • Combines the stack operations • Cannot undo, save a backup file 3D Modelling

  25. Editable Mesh Surface • Polygon mesh 3ds max v7 3D Modelling

  26. Edit face • Faces provide the renderable surface of an object. 3ds max v7 3D Modelling

  27. Extrude • Soft selection • Extrude • Bevel 3ds max v7 3D Modelling

  28. Activity • Make a crown • Create a tube • Convert to an editable mesh • Extrude polygons 3D Modelling

  29. Soft selection • The Soft Selection controls allow you to partially select sub-objects in the vicinity of an explicit selection • This causes the explicit selection to behave as if surrounded by a "magnetic field" 3ds max v7 3D Modelling

  30. Working with vertices • Select one or more vertices • Magnetic of soft selection • Use for transforms of vertices • The program applies a spline curve deformation to unselected vertices surrounding the transformed selected sub-object • A magnet-like effect with a sphere of influence around the transformation 3ds max v7 3D Modelling

  31. Activity • Create a sphere • Convert to an editible polygon • Push and pull vertices to make a face • Not easy! 3D Modelling

  32. Edit Edge • An edge is a line, visible or invisible, forming the side of a face and connecting two vertices • Two faces can share a single edge 3ds max v7 3D Modelling

  33. Optimization • Simplifies a smooth model with a high number of faces • Does not greatly change the model’s appearance 3ds max v7 3D Modelling

  34. Building Organic Forms • Humans are really hard to do • Working with Meshes and Vertices • Skinning • Working with cross-sections • Can be provided by a scan • Magnetic Resonance (MR) • 3D laser • Metaballs or Blobby surfaces 3D Modelling

  35. Metaballs or Blobby surfaces • Build a form from various sized objects • Blend the surfaces together into a single mass 3D Modelling

  36. Terrains • Terrain objects can be created from contour line data • Editable splines are selected • a mesh surface created over the contours 3ds max v7 3D Modelling

  37. Low polygon modelling • What happens to a game if the polycount in a model is too high? • Too slow to play • May crash the system • Overlapping meshes or undeleted faces may affect the appearance • Planning of low polygon models is important 3D Modelling

  38. Spec-ing a low polygon model • File format • Number and type of polygons • Use of texture maps • Particular type? • Colour depth? • Specific size? • Transparency? • Examine any sample models 3D Modelling

  39. Poly counts • Total number of polygons that make up a given object • 3D engines have limits • Number they can move around in a given scene • Software has a Polygon Counter utility • You can set a budget fop elected objects • Unnecessary polygons can be removed • Use MultiRes • Polygons can be made to look softer • Use MeshSmooth 3D Modelling

  40. Level of Detail • Models are created in two or more levels of detail • Use high polygon model when the object is large in the scene • Swap for the low polygon version when zoomed out • Used in VRML or X3D 3D Modelling

  41. Billboard • Define a flat surface which is camera aligned • Apply a texture • Renders faster than if a 3D object is used 3ds max v7 3D Modelling

  42. Box models and textures • Simple way to add detail • Keeps model simple • Box with a texture added • More later with materials 3ds max v7 3D Modelling

  43. Low poly techniques • No new skills • Greater precision • Decisions on where to invest detail • Decisions on where to simplify 3ds max v7 3D Modelling

  44. Mesh structure • Several meshes are attached to make a single object • Either • Weld the meshes together to form one mesh • Or separate them by a fractional amount • Do not intersect meshes • Delete any hidden faces 3D Modelling

  45. Game engines • Real time 3D engines may use rendering which smoothes out your model • You may need to take special steps to avoid this • Detaching groups to make them sharp 3D Modelling

  46. Self assessment • What are the four types of modelling concepts used by modelling software? • What is the most useful for gaming? • Why is this used for gaming? • Why does it not work well for • Rendered views? • Organic shapes? • Discuss the four methods of converting 2D shapes to 3D • Give an example of each for constructing everyday objects 3D Modelling

  47. References • Adventure Gamers : Dreamfall: from sketch to 3D model http://www.adventuregamers.com/article/id,477/p,2, accessed 23/09/2005 Giambruno M, (2002) 3D Graphics & Animation, 2nd Edition, New Riders, ISBN: 0-7357-1243-3 • Kerlow I. V., (2003) The Art of 3-D Computer Animation and Effects , 3rd Edition, John Wiley & Sons Inc; ISBN: 0471430366 • Murdock K. L., 3ds max7 Bible, Wiley Publishing; ISBN: 0-7645-7971-1 • Screen shots taken from 3ds max 7 User Reference and tutorials 3D Modelling

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