Questions tagged [shadow]

Shadows cast by objects in front of lights, whether raytraced, shadow maps, shadow volumes, or any other technique

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How to implement PCSS correctly?

I'm trying to implement PCSS in OpenGL/GLSL, but I have problems understanding the details especially the conversions between the coordinate spaces. The existing implementations are so different from ...
racz16's user avatar
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5 votes
0 answers
1k views

Cascaded shadow maps. Seams between cascades

I implemented cascaded shadow maps, where shadow maps for each cascade is rendered to one canvas: The light projections for each cascade are calculated from the bounding spheres of camera sub-...
Zheden's user avatar
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5 votes
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Dual paraboloid shadow texture edge seams

I implemented dual paraboloid shadows for point lights. The goal was to reduce the number of shadow passes. Also the target is GLES3.0 so no layered rendering is available. The shadows work, and ...
Michael IV's user avatar
5 votes
0 answers
1k views

Percentage-closer Soft Shadows implementation

I am trying to implement the Percentage-closer Soft Shadows (PCSS) from NVidia inside Unity but I am facing some issue and I don't know where they come from and then, I do not know how to solve them......
MaT's user avatar
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3 votes
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ray racing (Whitted) bad shadow on far objects (artifact)

situation: I've implemented a Whitted style ray tracing in C. Everything appear to works except the shadow cast by small object on big far objects The problem : red sphere have radius 0.5 orange ...
LesChats's user avatar
3 votes
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140 views

Shadow Mapping Errors

I recently started to create a shadow mapping system in OpenTK. I ran into a problem: The depthtexture is always completly white -> no depth. Even if the color from the shader is changed (I know it ...
Flamy's user avatar
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2 votes
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How can you efficiently get the last element occluding light when rendering shadows?

A long time ago I made an application that used volumetric rendering and I developed some shadowing equations that I felt very happy with, since they have pretty good results. For these equations to ...
Makogan's user avatar
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1 vote
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50 views

Variance Shadow Mapping (Shadow occurs when normal vector is close to light direction)

I am implementing Variance Shadow Mapping from Nvidia GPU Gems 3 Chapter 8: Summed-Area Variance Shadow Maps There they are talking about clamping the minimum variance to a very small value. I did ...
Thomas's user avatar
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1 vote
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117 views

Shadow Bug when Raytracing Triangles

Spheres with shadows work fine. But when I try to include triangles with shadows, they are shaded incorrectly (i.e completely black): But when I disable shadows Blinn shading on triangles work fine (...
fakhir's user avatar
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1 vote
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321 views

Voxel cone tracing artifacts (what causes them and how to solve them)?

I am trying to generate soft shadows using voxel cone tracing. Which gives me the next images: In the first image you can see an artifact of a sequence of horizontal shadows alternating with ...
Makogan's user avatar
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1 vote
0 answers
339 views

Handling shadow acne for dynamic surfaces

My path-tracer is generally fine and gives good output for regular test scenes, but I've noticed dense fireflies and dark speckles over fractal surfaces. The noise disappears if I render without light ...
Paul Ferris's user avatar
1 vote
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What could cause realtime lighting within a viewport to be calculated on the wrong part of the screen?

(I initially posted this in a section that is less suited for the particular issue, oops) I'm having this issue on some of my client's computers (this is for a Unity asset) that I cannot reproduce on ...
Phygon's user avatar
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262 views

Changing coordinate system from texelFetch to textureLod is breaking the algebra

I have a scene rendered using texelFetch() and I am trying to modify the shader to use textureLod() instead. This is the image generated with texelFetch: When I try to change the shader to use ...
Makogan's user avatar
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