Chapt 7 3D真实感图形技术——计算机图形学课件PPT

Scene graph Object geometry
Modeling Transforms
Lighting Calculations
Viewing Transform
Objective :
• Scene vertices in 3-D “view” or “camera” coordinate system
Projection Transform
• 2-D screen coordinates of clipped vertices
The Rendering Pipeline: model transforms
Scene graph Object geometry
Objective:
Modeling Transforms
Up direction (ux, uy, uz)
Aperture
Field of view (xfov, yfov)back Film plane
“Look at” point
View plane normal
right
View Plane
Up direction
“Look at” Point
Framebuffer
Display
3D Model
3D Geometric Primitives
Point Line segment Polygon Polyhedron Curved surface Solid object etc.
H&B Figure 10.46
Camera Models
Rendering
Geometric Primitives
Raster Image
Rendering 3D Scenes
Transform Illuminate Transform
Clip Project Rasterize
Model & Camera Parameters
Rendering Pipeline
Camera is as man’s eye:
View plane
Eye position (focal point)
Camera Parameters
Position
Eye position (px, py, pz)
Orientation
View direction (dx, dy, dz)
Lighting Calculations
• All vertices of scene in shared 3-D “world” coordinate system
• Modeling transform
Size, place, scale, and rotate objects and parts of the model
Clipping
Projection Transform
The Rendering Pipeline: Clipping
Scene graph Object geometry
Modeling Transforms
Lighting Calculations
Viewing Transform
ObjectБайду номын сангаасve :
The Rendering Pipeline: scene
Scene graph Object geometry
Result:
Modeling Transforms
• All vertices of scene in shared 3-D “world” coordinate system
Lighting Calculations
• Vertices shaded according to lighting model
Viewing Transform
• Scene vertices in 3-D “view” or “camera” coordinate system
Clipping
• Exactly those vertices & portions of polygons in view frustum
Modeling Transforms
Lighting Calculations
Viewing Transform
Objective :
•All geometric primitives are illuminated
Clipping
Projection Transform
The Rendering Pipeline: viewing transform
3D游戏图形开发
3D Rendering Pipline Excise
华东师范大学软件学院 王长波 博士
真实感场景绘制：
计算机图形输出设备上绘制出能够以假乱真的景象。
纲要
算法原理回顾 D3D程序实现 编程演示 练习题
Rendering
Generate an image from geometric primitives
• Remove geometry that is out of view
Clipping
• Object coordinates -> world coordinates
Viewing Transform
Clipping
Projection Transform
The Rendering Pipeline: lighting calculations
Scene graph Object geometry
Rendering Pipeline
Framebuffer
Display
Rendering: Transformations
3D scene
2D image .
They are used in three ways:
Modeling transforms Viewing transforms Projection transforms
Eye Position
Moving the camera
Up
Back
Towards
Right
View Frustum
The Rendering Pipeline
Transform Illuminate Transform
Clip Project Rasterize
Model & Camera Parameters