Turner Whitted Ray Tracing CS 351-50 No Bounces 1 One Bounce - - PDF document

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Mar 01, 2023 8 likes •70 views

Turner Whitted Ray Tracing CS 351-50 No Bounces 1 One Bounce Two Bounces Reflection Ray n I = incident ray = -d R -I N = normal vector R = reflected ray ( -I . N) N ( -I . N) N N -I + (-I . N) N -I - (-I . N) N R -I

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1 Ray Tracing

CS 351-50

Turner Whitted No Bounces

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2 One Bounce Two Bounces Reflection Ray

R = ( -I . N) N - I + (-I . N) N = -I - 2 (I . N) N N θ θ

n R θ θ

( -I . N) N

I - (-I . N) N

R

( -I . N) N

I + (-I . N) N

I = incident ray = -d N = normal vector R = reflected ray

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3 Adding an object: transparency Refraction

n sin θ = nt sin φ

Index of Refraction > 1

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4 Index of Refraction < 1

total internal reflection

Algorithm

Trace (ray){

For each object in scene

intersect (ray, object) If no intersections

return background_color

Color = c_a * c_r (Ambient * reflected diffuse color of surface) For each light

for each object in scene

intersect(shadowRay, object) Accumulate local illumination

Trace (ReflectionRay) Trace (TransmissionRay) Accumulate global illumination Return illumination }

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5 Sampling Ray Tracing Demos

http://www.siggraph.org/education/materials/HyperGraph/raytrace/rt_java/raytrace.html

http://www.cs.berkeley.edu/~efros/java/tracer/tracer.html

Sampling Demo Texture & Materials

SLIDE 6

1

Ray Tracing