Questions tagged [occlusion]
9 questions
11
votes
2 answers
With modern fillrates and deferred rendering, is occlussion culling still relevant?
For example, while it's the current top-of-the-line GPU, the GTX 980 has a staggering 72.1 gigapixels/second fillrate, which with back-to-front rendering and/or Z buffer checks, seems almost ridiculously large, possibly even at 4k resolutions. As…
Llamageddon
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10
votes
1 answer
Sphere intersection occlusion (for hybrid raytracing)
Thinking about hybrid raytracing, hence the following question:
Suppose I have two solid spheres $s_1$ and $s_2$. We know their centres and radii, and we know that they have some overlapping volume in space.
We have a typical 3D graphics setup:…
occulus
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8
votes
1 answer
What is occlusion?
Occlusion "is the effect of one object in a 3-D space blocking another object from view."
With this definiton in mind I cannot understand sentences like:
The interior of a tube is typically more occluded (and hence darker)
than the exposed outer…
Joey
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5
votes
1 answer
How can I get a spherical visibility mask map for a point on a concave surface?
I encountered this problem doing my project. Suppose there is a 3D mesh model, e.g. a human face, I need the 3D visibility map at each of the vertices of this model. By the "3D visibility map", I mean the binary image covering the spherical surface…
user1692
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3
votes
1 answer
How to deal with light leaks?
I'm struggling with light leaking through meshes (especially thin ones) due to interpolation between probes located on the opposite sides of those.
First approach I took was mapping all static geometry to 1 lightmap, then generating light probes…
Pavlo Muratov
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2
votes
1 answer
A solution to sprite visibility in a raycasting engine with variable wall heights?
I am writing a raycasting engine. At this point, I have added sprites, and I am using a z-buffer, with one stored length to a wall for the x coordinate of each ray. Below is an image of a sprite which is fully visible.
Z-buffering works fine when…
Caspian Ahlberg
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1
vote
2 answers
Techniques for rendering high polycount models
I would like to know what common techniques are used for rendering large models, when using rasterisation within a graphics API, for example OpenGL or Vulkan.
For example if I had a model with >10 million triangles, and it would be too slow to…
tester
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0
votes
1 answer
How to implement falloff control in brute force ambient occlusion?
My AO algorithm is as follows, whith the random vectors just all over the hemisphere:
vec3 ao_ray_position= random_in_hemisphere(gi_rec.normal);
ao_ray = ray(gi_rec.p + gi_rec.normal * 0.001f, ao_ray_position);
ao_hit =…
mrmanet
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0
votes
0 answers
How to sprite cast in a raycasting engine?
I'm trying to render sprites/textures in my raycasting engine, but I don't quite understand the math behind drawing the columns of the texture I intend to project. I've tried looking at several tutorials, e.g., lodev, Wynnliam, and several posts on…
Joshua Crotts
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