Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Questions tagged [reflection]

41 questions
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Radiosity VS Ray tracing

Radiosity is basically what allows this: In a tutorial of Cornell University about Radiosity it is mentioned that: A ray-traced version of the image shows only the light reaching the viewer by direct reflection -- hence misses the color…
Armfoot
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Choosing Reflection or Refraction in Path Tracing

I am trying to implement refraction and transmission in my path tracer and I'm a bit unsure on how to implement it. First, some background: When light hits a surface, a portion of it will reflect, and a portion will be refracted: How much light…
RichieSams
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Polarising reflection and refraction for a wrap around water surface

I want to render realistic images of water in an orbiting space habitat. The image does not need to be generated in real time, although I wouldn't want it to take weeks either. I'm looking for an approach that can generate realistic images in hours…
trichoplax is on Codidact now
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What is the difference between glossy and specular reflection?

What is the difference between glossy and specular reflection? What is their relations with BRDF?
chaosink
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7
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Fresnel equation with incident angle, n and k as input

I've seen a Fresnel equation for calculating the reflection amount at incidence angle with n and k values defined. This formula usually comes up in relation to computer graphics, but I can't find this equation anywhere in a science context. Here is…
Kristoffer Helander
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6
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fix over exposure in importance sampling in screen space reflections

I am having my first encounter with the rendering of indirect reflections in the form of screen space reflections in a game engine, but i am struggling to get correct looking results. (patterns arise from a bad way of generating noise for…
Sebastián Mestre
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realtime dynamic reflections, which way to go?

I'm working on my own engine and I'm struggling to find any techniques that give okay-ish reflections in realtime on dynamic scene. So far the only technique I found that work in real time on dynamic scene is SSR but it's really heavy and have a lot…
newin
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5
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How to choose which reflection probe to use?

I have multiple reflection cube map that's prebaked before a scene. However I am being confused as to which one to choose. I am told I need to choose "closest cube map" then use it. However it is unclear to me that whether I should do that based off…
Blue Bug
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Mirror Reflections: Ray Tracing or Rasterisation?

Are mirror-like reflections in computer graphics purely handled with ray-tracing/ray-casting techniques or are there some situations where they are achieved through rasterisation?
Will D
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Refraction in a Ray Tracer: What do with an intersection within the medium?

I am currently following a tutorial at Scratchapixel.com on refraction Here is the refract function: Vec3f refract(const Vec3f &I, const Vec3f &N, const float &ior) { float cosi = clamp(-1, 1, dotProduct(I, N)); float etai = 1, etat =…
Arjan Singh
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Should not specular reflection on a rough surface be similar to diffuse reflection?

Different BRDFs are usually used to compute diffuse and specular reflection. Some of the most often used include for example the Lambert BRDF for diffuse reflection and the Cook-Torrance BRDF for specular reflection. Cook-Torrance BRDFs are…
wip
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How to handle specular highlights with reflection / total internal reflection in a ray tracer?

Let's say that I have a raytracer that is rendering a scene that includes a refractive object. When a ray hits the refractive object, I know that I can use the fresnel equation (Schlick's approximation in my case) as well as the object's base…
Alan Wolfe
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Normal mapping for planar reflections

Ok guys, tricky one! I'm trying to modify this Unity script + shader to include normal mapping. The tl;dr is, it uses a single texture rather than a cubemap as it is only for reflecting in a planar surface. So it doesn't use the standard ray bounce…
russ
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What to reproject when doing temporal filtering in stochastic screen space reflection?

I am in the middle of implementing stochastic screen space reflection based on frostbite presentation here. On page number 39, it is stated that we need to reproject the ray intersection location instead of the reflected surface location. I don't…
kevinyu
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3
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Tracing shadow rays in a scene with mirrors

In my real time ray tracer, I shoot primary rays from the eye, and at hit points, I trace to a single light source to determine if the object is shadowed or lit. Pretty straightforward stuff so far. However I have recently added perfect mirrors to…
Bram
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