Rendering

• Rendering: The process of generating an image from a model, by means of a computer program

  Model -> Rendering -> Image -> Display

  • image + model - comp = painting, photography
  • model + comp - image = 3D printing, hydrographic printing, sound rendering
  • image + comp - model = abstract graphics

• Realism

  • Shadows
  • Reflections
  • Transparency
  • Translucency
  • Textures
  • Complex illumination
  • Realistic Materials

• Components

  • Scene geometry
  • Camera
  • Light sources
  • Materials
  • Light propagation

• Application

  • 影视特效
  • 动画
  • 三维游戏（Performance，速度要快）
  • 工业设计
  • 文化遗产保护
  • 虚拟现实（Performance）

Ray Casting (Appel, 1968)

• a simple version version of ray tracing
• 发射光线 -> 获得交点 -> 计算光源贡献

ray = rayThruPixel(cam, i, j)
hit = Intersect(ray, scene) //瓶颈
image[i][j] = findColor(hit)

• 不考虑阴影，反射
• 只考虑 direct illumination

前沿进展

GradNet (2019 SIGGRAPH)

• 去噪
• Gradient-domain Rendering: Off-path 计算梯度
• 主图+两张梯度图去噪：优化方程
• 增加约束项：速度慢 -> 用网络模拟过程
• Deep learning based, unsupervised, fast to reconstruct high-quality image

Deep Shading (EGST 2007)

• Convolutional Neural Networks
• U-net

Deep Illumination (arXiv)

• GAN

2019 年图灵奖

• Edwin Catmull
  • Z-buffering
  • Texture mapping
  • Catmull-Clark subdivision
• Patrick Hanrahan
  • Volume rendering
  • Subsurface scattering
  • Light Field rendering
  • Tableau
• 1995 玩具总动员
• RenderMan