Lecture #06. Ray tracing. Camera rays

Recall: rasterization pipeline

Cornell box

Rasterizer vs original

Definitions

Shading is how surfaces are “painted” with light

Shadow is a dark area formed by occluded light source [1]

Turner Whitted demo (1979)

Ray tracing idea

Wave–particle duality of light

Mathematical definition of ray

\[ray(t)=\vec{origin}+t*\hat{direction}\]

\[t>0\]

Raytracing pipeline

[5]

Ray generation

Ray generation method generates primary rays (camera rays) and call Trace ray to evaluate the final color of each trace.

Pinehole camera model

Camera ray-casting

[6]

Miss shader

Miss shader is called when Trace ray haven’t found any intersection

[5]

Default scene

Miss sharer is used to generate a scene without geometry. Could be pure color, sky, terrain, etc

by Morgan McGuire

Lab: 2.01 Ray generation

1. Implement set_render_target, set_viewport, and clear_render_target methods of raytracer class
2. Add render_target, camera, and raytracer in ray_tracing_renderer class
3. Implement ray_generation and trace_ray method of raytracer class
4. Implement miss_shader, image clearing, calling ray_generation, and saving in ray_tracing_renderer class