Ray tracing is a technique for rendering images that simulates the physical behavior of light. It involves tracing the path of light as it interacts with virtual objects in a simulated scene. The key aspects of ray tracing include modeling reflection, refraction, color intensity and shadows produced by light sources. It produces highly realistic images but can be computationally expensive compared to other rendering methods.

1. RAY TRACING
Presented By
Muhammad Azam Sohu
Farhana Shaikh

2. RAY TRACING
• Ray Tracing is an advanced technique for
adding realism to an image by including
refraction, reflection, color intensity, and
shadows that would be produced by
having one or more light sources.
• This means you can create pictures full of
mirrors, transparent surfaces, and object
shadows, with stunning results.

3. Ibn al-Haytham - The Nature of Light
and Vision
Ibn al-Haytham was the first to explain that we see objects because
the rays of light can reflected from objects into our eyes.
Two interesting remarks can be made based on his observations:
* Firstly, without light we cannot see anything and
* Secondly, without objects in our environment, we cannot see light.

4. Compared to the total
number of rays
reflected by an object,
only a select few of
them will ever reach
the surface of our eye.

5. Nature of light and Ray Traced Image

6. Backward Ray Tracing
A ray tracing program
mathematically identifies and
reproduces the path that each
light ray follows in reverse
direction from the eye back to
its point of origin.

7. Shadow in Ray Tracing
In the figure we see two rays:
a and b, which intersect the purple
sphere.
To determine the color of a, we follow
the new ray a' directly towards the
light source. The color of a will then
depend on several factors.
b will be shadowed because the ray
b' towards the light source is blocked
by the sphere itself.

8. Reflection And Refraction in Ray Tracing
To handle reflection we also consider multiple bounces from
objects, and to handle refraction we consider what happens when
a ray passes through a partially- or fully-transparent object.

9. Basic Ray Tracing Algorithm
For every pixel
{
Cast a ray from the eye for every object in the scene
Find intersections with the ray
Keep it if closest
}
Compute color at the intersection point

10. Advantages Of Ray Tracing
* It provides a realistic simulation of lighting.
* Effects such as reflections and shadows are
a natural result of the ray tracing algorithm.

11. Disadvantages Of Ray Tracing
* A serious disadvantage of
ray tracing is performance
because it treats each eye
ray separately.
* Advanced lighting effects
such as caustics are difficult
to render usin ray tracing.

12. Thank you
Any questions ?