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Ray Tracing - Coggle Diagram
Ray Tracing
Definition
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Viewing frustum - 3D volume that is visible, and thus shows up on the screen
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Pixel - a small region of a monitor, an addressable location in a frame buffer, a small region on the image plane in the 3D virtual world
Foward ray tracing
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Computer implementation:
- Consider one light source, generate rays emitted in all direction
For each ray, trace its path until
Hitting nothing, the ray strikes the eye.
Hitting an object, the ray reflects into the eye. Modify the ray by its intersection point with the object and store its intensity
Hitting a transparent object, the ray reflects and passes into the eye. Modify the ray by its interaction and store its intensity
The ray reflects from a number of objects and hits the eye. Modify the light by each interaction and store the final value
The ray misses the eye, ignore it
Analysis - colour arriving at a square (pixel on a computer screen) is determined by the light arriving at the eye through the corresponding hole in the card
Light comes from
- Light sources
- Reflecting surfaces
- background (ambient light)
Theory
A redering technique that calculates an image of a scene by shooting rays into the scene.
- The scene is built from shapes, light sources, a camera, materials, special features
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A technique for image synthesis, creating a 2D picture of a 3D world
Ray Casting
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Comments :
- Allows for simple illumination;
- No reflections/refractions
- Images look very flat
- Can be very fast
- A very parallel solution
- Can be extended to ray tracing by adding more rays
- Can be specialized for rendering terrain
