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4.21. Adjust the uv coordinates in the UV Editor...
We can use:
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4.23. The "completed" head model
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4.24. The End
5. 5 Character Modelling II. Modelling the body
5.1. Start
• http://cg.iit.bme.hu/gamedev/KIC/02_DevToolsAssets/04/
• Load head.blend into Blender
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5.2. New Cylinder
5.3. Set background image in front view
Set background image in front view: torso_front.jpg Rotate cylinder to look like this:
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5.4. Move vertices to their place
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5.5. Refinement (loop subdivide), vertex position adjustment:
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5.6. Delete cap faces
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5.7. Set background image for side view (torso_side.jpg)
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5.8. Move vertices to their place in side view
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5.9. Extrude the shoulders, adjust vertex positions
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5.10. Extrude the collar (torso.blend)
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5.11. Extrude the arm, adjust vertices
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5.12. Help
Help: Front view image (arms_front.jpg) extrude, scale...
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5.14. Creating legs
Creating legs is similar.
Details are up to you!
We can use: extrude, scale, rotate faces
(cut faces (knife cut), vertex merge, create new faces etc...)
5.15. legs.blend
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5.16. We also need:
• Hands (glove)
• Foot (shoes)
• Accessories (back sack, belt, sunglasses etc..)
• TEXTURING
• Refinement of the whole model
6. 6 Character animation in Blender - Rigging
6.1. Start
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6.2. Create one bone of a skeleton
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6.3. Create new bones
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6.5. Name the bones (_l postfix)
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6.6. Renaming the bones
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6.7. Bind geometry to the skeleton
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6.8. Test (skeleton can be posed in Pose mode)
6.9. Undo transformation of a bone
6.10. Vertex groups
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6.11. Bone weight painting
Red: high influence (1.0) Blue: low influence (0.0)
6.12. Just paint weights until we are satisfied...
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7. 7 Game engine modules
7.1. What is a game engine?
• An extremely complex software package
• A class library
• Additional tools
• level editors
• modeling software plugins
7.2. Tasks of a game engine I
• Multi-threading
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• Rendering
• resource (tesh, texture, shader) management
• material/shader system
• GPU state change management
• geometry instancing
• visibility culling
7.3. Tasks of a game engine II
• Animation
• Physics simulation
• Character animation
• Particle systems
• Camera animation
• Audio
• GUI
7.4. Tasks of a game engine III
• Artificial intelligence
• state management
• pathing
• Scripting
• Procedural content generation
• global illumination
• vegetation generation
• Networking
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7.6. Multi-threading library?
• There are some, e.g.
• Intel Thread Building Blocks
• Microsoft Parallel Patterns Library
• but the challenge is to design engine modularization, parallelism, communication, task granularity
• for garage projects giving their own thread to physics and audio suffices
7.7. Rendering - resource management
• Mesh models, textures, shaders must be loaded from files
• Streamed/removed from CPU/GPU memory
• Game objects can reference these resources
• Intermediate buffers, render targets
7.8. Rendering - material/shader system
• New materials should be editable, changeable without touching the code: a kind of scripting is needed
• e.g. Ogre's material scripts
• e.g. the Effects system of D3D
• Assignment of materials to game objects
• Application of material for rendering
7.9. Rendering - GPU state change management
• GPUs are fast - CPU-GPU communication is the bottleneck
• to minimize this, minimize state changes
• render objects with the same materials, textures contiguously
• render queues
• geometry instancing
7.10. Rendering - Visibility culling
• Do not render hidden geometry
• View frustum culling
• PVS - possibly visible set
• a conservative guess on what is visible
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• if a proxy object inside A fully occludes a proxy object around B, then B is surely not visible
• hierarchies
• GPU support - visibility queries
• when rasterizing proxy of B, did we draw anything?
7.11. Rendering Engine
• Ogre3D
• Crystal Space
• Genesis3D
• Irrlicht
• Truevision3D
7.12. Animation - Physics simulation
• The virtual world should not only look real - it should act real!
• Rigid body mechanics
• Collision detection and response
• Contact forces and joints
• Cloth simulation
• Fluid simulation
7.13. Physics Engine
• Bullet
• open source
• ODE - Open Dynamics Engine
• NVidia PhysX
•
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• input: bone orientations at keyframes
• skinning
8. 8 Rendering pipeline - Ogre3D
8.1. Pipeline stages I.
• Prepare vertex data
• Vertex Shader
• World and View transformation
• Shading
• Projection Transformation
• Make up primitives
• Geometry Shader [sm4, DX10]
• Additional geometry creation
8.2. Pipeline stages II.
• Rasterization
• Backface culling
• Clipping
• Homogeneous division
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• Viewport transformation
• Pixel shader
• Defining pixel color
• z-test
• blending
8.3. Preparing vertex data
• Vertex buffer
• Array of vertex records
8.4. Vertex shader
• Input data
• varying: [position, normal, color, texture coordinates, ...]
• uniform: model, view, projection matrices, light data, ...
• Output data
• Position in homogenous screen coordinates
• Shaded color
• Other data [normal, texture coordinates]
8.5. Primitive assembler
• non-indexed / indexed
• Adjacent vertices define a triangle
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8.6. Backface culling
• Based on vertex order (clockwise, counter clockwise)
• If the model has a consistent vertex ordering (preferable)
• The model should be a closed shell
8.7. Clipping
• Offscreen triangle parts are cut
• normalized screen coordinates[-1, -1, 0] [1, 1, 1] [Cartesian]
• Wrap-around problem
• Clipping in homogeneous coordinates
8.8. Rasterization
• Homogeneous division
• Viewport transformation: pixel coordinates
• Linear interpolation
• Interpolation of vertex output data for each covered pixels
• Execute pixel shader for each covered pixel
8.9. Pixel shader
• Input data
• vertex shader output data, linearly interpolated
• pixel coordinates
• Output data
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• pixel color [RGBA]
• Pixel depth
• Optional, interpolated values can be overriden
• If not overriden: early test
8.10. Output merger
• buffers
• target: frame buffer or texture
• depth-stencil buffer
• operations
• Depth test
• Stencil test
• Alfa blending
8.11. Z-test
• Solution for visibility problems
8.12. Blending
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8.13. "Standard" vertex shader (Cg)
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8.14. "Standard" pixel shader
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8.16. Phong shading
8.17. Ogre3D
8.18. Object-Oriented Graphics Rendering Engine
• www.ogre3d.org
• Manual
• API reference
• SDK
• Demos
• Tools (exporter)
• Wiki
• Forum
8.19. Object Oriented
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• Main interfaces are independent from:
• 3D API
• Scene type
• Platform
• Extendable
• plugins
• Clear design
8.20. Features
• Multi platform
• Various scene graph management
• Resource management
• Dedicated model format
• Level of detail
• Skinning
• Morphing
• Material scripting system (XML)
• Render state
• Textures(2D,3D,CUBE,animated)
• Shaders
• Particle system (scripts)
• Common shadow computation methods
• Render to texture
• Post processing framework (scripts)
• Overlay framework (scripts)
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8.21. Basic Ogre usage
OgreRoot root = new Root(...);
root.loadPlugin("RenderSystem_Direct3D9");
RenderSystemList list = root.getAvailableRenderers();
root.setRenderSystem(list.at(0));
root.initialise(...);
RenderWindow renderWindow = root.createRenderWindow(...);
SceneManager sceneManager = root.createSceneManager(...);
ResourceGroupManager.getSingleton().addResourceLocation(...);
ResourceGroupManager.getSingleton().initialiseAllResourceGroups();
setupScene();
setupListeners();
root.startRendering(); //main loop ( )
8.22. setupScene
SceneNode rootSceneNode = sceneManager.getRootSceneNode();
camera = sceneManager.createCamera("Main Camera");
camera.setPosition(0, 10, 20);
Viewport viewport = renderWindow.addViewport(camera, ...);
renderWindow.setActive(true);
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Entity entity = sceneManager.createEntity("cake", "zuh.mesh");
SceneNode cakeNode = rootSceneNode.createChildSceneNode();
cakeNode.attachObject(entity);
cakeNode.setPosition(-3.5f, 0, 0);
8.23. setupListeners
8.24. Material script (.material)
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8.26. Shader program definitions (.program)
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8.27. The End
9. 9 Ogre3D
9.2. Media files
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Win32 Console Application
9.4. Settings for all configurations
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9.6. Required dlls (files ending with _d are from the debug folder, others are from the release folder)
9.7. OgreLab1.cpp
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9.8. Test: build and run
9.9. Log file
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9.10. Camera / viewport
9.11. Test
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9.12. Exported Ogre meshes
9.13. Test
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9.14. Several copies of the model
9.15. Test
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9.16. Lightsource!
9.17. Test
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9.18. Animated light
9.19. Test
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9.20. Ground
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9.21. Test
9.22. Tessellated ground
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9.23. Test
Don't forget to set segmentation back to 1!!
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9.25. Test
9.26. Shaders / Phong shading
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9.27. Shaders / Phong shading
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9.28. Test
Yes, this is our shader!!!
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9.29. Test
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9.30. Test
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9.31. Test
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9.32. The End
10. 10 Billboard, Particle System
10.1. Basics
• http://cg.iit.bme.hu/gamedev/KIC/04_GraphicsEngine/
• 04_03_Ogre3D_BillboardsParticles_Base.zip
• Extract
• Run: OgreBillboardParticles.sln
• Set include and library paths (if not correct)
• Set working directory (if not (SolutionDir)/bin)
• Compile
• Run
10.2. Run
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10.3. New file: Tree.h
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10.5. OgreBillboardParticles.cpp
10.6. Test
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10.7. Blending
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10.9. Several trees
10.10. Test
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10.11. No depth buffer write
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10.13. Sorted rendering of transparent objects
• Individual work: Rewrite the code to contain only one billboard set which should contain all billboards
• Take care of:
• Ordering
• Culling
• Pool (maximal size of the billboardset)
10.14. Solution
10.15. Test
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10.16. A more realistic approach: Billboard Clouds
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10.17. A more realistic tree
10.18. Tree.material: new material
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10.19. Test
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10.20. Tree.material: new material
10.21. Test
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10.22. Particle systems
10.23. New file: Particles.h
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10.24. New file in media folder: example.particle
10.25. New material file: Particles.material
10.26. OgreBillboardParticles.cpp
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10.27. Test
10.28. Individual Work
Explore the scripts, play with them, try several:
• Emitters
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