2022-10-24 11:04:36 -04:00
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---
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title: "Vulkan Deep Dive: Parallax-corrected Reflections and Real-time Image-based Lighting"
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date: 2022-10-05
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draft: true
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tags:
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- Vulkan
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- C++
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- Deep Dive
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---
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You might be wondering why I'm covering reflections and IBLs in this series, as there
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2022-10-26 09:21:14 -04:00
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is tutorials covering these already online.
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<!--more-->
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However, there is two important distinctions in what I'm
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2022-10-24 11:04:36 -04:00
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teaching here:
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_Parallax-corrected_ reflections and _Real-time_ Image-based Lighting. In most tutorials, they might cover
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simple screen space reflections, or if you're lucky - cubemap-based solutions. Most image-based lighting tutorials also
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2022-10-26 08:53:53 -04:00
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limit themselves to existing HDRIs for simplicity, but doing it in real-time or offline when building levels
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2022-10-24 11:04:36 -04:00
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is arguably the more popular option in games, so it's harder to figure out that yourself. As always, let's dig in!
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Although I'm covering two topics this time, I did it because they're tangentially related, but I won't be compromising on
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the details.
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## Parallax-corrected Reflections
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This is something I've been wanting to cover for a long time, because despite still being popular in games, there is very
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little information out there on how to accomplish this. For clarity, this is an extension of cubemap-based realtime (or offline) reflections
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using some kind of probe globally or locally. The main difference is for regular reflections, there is no concept of it occupying
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2022-10-25 17:45:27 -04:00
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any real physical space, it's freestanding and doesn't look correct. For really rough or small reflections, it works okay but
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2022-10-24 11:04:36 -04:00
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look at how it looks in a watery environment:
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And now with parallax-corrected:
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As you can see, it's very convincing at most angles, and doesn't suffer from the downsides of screen-space reflections.
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### Theory
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### Implementation
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## Real-time Image-based Lighting
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This tutorial assumes that you _already_ implemented image-based lighting in your engine, as I won't dig into that here
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(There is much smarter people to tell you how to do that!) This will just cover how to move from existing HDRI to one that is scene-based.
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### Theory
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_Note:_ This isn't really anything to do with any mathematical theory, but it's still a good subsection title ;-)
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### Implementation
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