a technique for generating an image by tracing the path of light through pixels in an image plane and simulating the effects of its encounters with virtual objects

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1answer
152 views

C++ Ray Traversing in 3D Voxel game

I'm currently working on a Voxel game in 3D and need a tad bit of help to figure out what Voxel the player is looking at. This is the data I currently have: GRRLIB_Camera3dSettings(Player.x, ...
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1answer
182 views

How to calculate ray polygon intersection? [duplicate]

I'm in a class where we are creating a ray tracer from the ground up in C++. I'm at a point where I can't seem to wrap my head around the math that is required to calculate the point at which a ray ...
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0answers
106 views

Ray-Triangle Intersection Detection using Barycentric Coordinates

I am attempting to convert the algorithm from http://www.cbloom.com/3d/techdocs/fast_ray_tri.txt to java code, but my solution does not function correctly. The only intentional change I made was for ...
8
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1answer
274 views

Specular banding with high specular power

We're having some issues with our ray tracing in DirectX, especially with some serious banding issues with specular. With high specular power (above 8) banding starts. I'm wondering if this is an ...
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1answer
107 views

Degenerate AABB (axis aligned bounding box), does this always intersect?

I'm studying ray-AABB intersections and I'm asking myself: what would happen if one of the dimensions of the axis aligned bounding box was degenerated? For instance: AABB_min = {1,1,1} AABB_max = ...
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1answer
745 views

Rendering lightmaps at runtime

I'm creating a procedural terrain system for Unity. And I'm looking for ways to efficiently cast self-shadows on it. If it wasn't procedural, I could simply bake a lightmap using Beast. But, I can't ...
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1answer
171 views

Overlapping sibling problem in AABB tree

I'm trying to make a real-time GPU (CUDA) ray tracer, and for now I'm tracing single rays, but I've ran into a problem: the BVH. This [PDF]paper has been my inspiration for the theoretical part, and ...
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1answer
428 views

Ray Tracing in 3D - generating a ray

A ray is shot from the camera eye to the camera screen at point (i,j) how do I get the coordinates of that point in 3D world coordinates? The best I could find online is for point S S = Q + au + bv ...
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2answers
400 views

Raytracer texture mapping (to triangle mesh) leaving artifacts

So I am trying to get OBJ loading working in my raytracer. Loading OBJs works fine, but I am having some trouble with getting the texture mapping working. Here is an image of my result. It is ...
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2answers
335 views

What is the state of the art of ray tracing on the GPU?

I think ray trace rendering had to be done on the CPU for a long time. But since we have compute shaders in OpenGL 4.3 now, it might be possible to move the computations on the GPU and perform ...
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2answers
224 views

How does a point squared equal the radius squared?

I am working on a simple ray tracer but I don't understand some of the formulas. One that is bugging me at the moment is this: If a sphere is centred at origin, a point p lies on a sphere of ...
4
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1answer
141 views

Forcing early-z with raytracing

I'm working on a GLSL raytracer, and I need to be able to edit gl_FragDepth in the FS. However, doing so disables early-z culling. The scene is rendered front-to-back and the FS can only push points ...
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1answer
548 views

Ray Tracing Shadows in deferred rendering

Recently I have programmed a raytracer for fun and found it beutifully simple how shadows are created compared to a rasterizer. Now, I couldn't help but I think if it would be possible to implement ...
2
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1answer
205 views

Ray Tracing concers: Efficient Data Structure and Photon Mapping

I'm trying to build a simple ray tracer for specific target scenes. An example of such scene can be seen below. I'm concerned as to what accelerating data structure would be most efficient in this ...
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3answers
647 views

Real-time ray tracing: How is it done?

I wonder what technology applications like Xara3D use to be able to perform real-time ray tracing. How is such good quality rendering done in real-time?
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1answer
474 views

What is an easy way to work subsurface scattering into a raycaster?

I've got some neat effects with path tracing: I want to add in an ability to do subsurface scattering, but I'm unsure of the general algorithm. With path tracing, it's: foreach pixel: trace( ...
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4answers
1k views

Impact of variable-length loops on GPU shaders

Its popular to render procedural content inside the GPU e.g. in the demoscene (drawing a single quad to fill the screen and letting the GPU compute the pixels). Ray marching is popular: This means ...
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1answer
506 views

Intersecting Ray with Extruded 2D Shapes (e.g. Extruded Text)

I'm looking for a way to find intersection between a ray and an extruded 2D shape or text (defied by a Bézier curve). Any ideas?
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3answers
292 views

Why Inverse Transform the Ray when doing Transformation?

I am adding 3D affine transformations to my ray tracer, and it seems all the literature on the web recommend inverse transforming the ray instead of transforming the 3D objects. Why is that? There ...
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1answer
373 views

How to calculate the viewing cone radius at a distance in raymarching?

I'm "raymarching distance fields" (proper lingo: sphere-tracing) in GLSL. To implement cone-marching atop of it (and also to minimize the number of raymarching steps regardless of whether ...
3
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1answer
362 views

Procedural mesh generation from raytracer

I'm interested in applying the following technique: Define game objects using a object definition DSL similar to what you would use for a raytracer (e.g. POVRay) Use a specialised raytracer to ...
1
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1answer
322 views

Realtime rendering using a ray tracing engine

I want to render an object that has a mesh with one million hexagonal elements(100 * 100 * 100). Lights, shadows and textures is not important and each element has a solid color. and finally, the ...
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1answer
221 views

3D Huge mesh rendering

I am writing a program, that as input, I have a huge (10^6 elements) 3d mesh (with hexagonal shaped elements), and I want to realtime render it, but not as real-time as a game. It just can show the ...
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1answer
2k views

Fast pixelshader 2D raytracing

I'd like to do a simple 2D shadow calculation algorithm by rendering my environment into a texture, and then use raytracing to determine what pixels of the texture are not visible to the point light ...
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2answers
234 views

Which optional features would you recommend for a raytracer? [closed]

I'm developing a basic triangle mesh raytracer on a short deadline. This means I can't implement every feature I come across, so I'm looking for some feedback about which features you think are most ...