{"id":120572,"date":"2020-11-12T16:01:00","date_gmt":"2020-11-12T16:01:00","guid":{"rendered":"http:\/\/www.gamasutra.com\/view\/news\/373651"},"modified":"2020-11-12T16:01:00","modified_gmt":"2020-11-12T16:01:00","slug":"the-bright-side-of-ray-traced-global-illumination","status":"publish","type":"post","link":"https:\/\/sickgaming.net\/blog\/2020\/11\/12\/the-bright-side-of-ray-traced-global-illumination\/","title":{"rendered":"The bright side of ray-traced global illumination"},"content":{"rendered":"
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http:\/\/www.gamasutra.com\/blogs\/RubenTorresBonet\/20201110\/373493\/\" target=\"_blank\" rel=\"noopener noreferrer\"><img decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-1.gif\" alt=\"Share on Twitter\" border=\"0\" height=\"20\"><\/a> <span id=\"edit_post_link\"><\/span> <a href=\"https:\/\/www.gamasutra.com\/blogs\/rss\/\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-2.gif\" width=\"15\" height=\"15\" border=\"0\" alt=\"RSS\"><\/a> <\/div>\n<hr>\n<div class=\"item_body mobile_image_transform\"> <strong><i><small> The following blog post, unless otherwise noted, was written by a member of Gamasutra\u0092s community.<br \/>The thoughts and opinions expressed are those of the writer and not Gamasutra or its parent company. <\/small><\/i><\/strong> <\/p>\n<hr>\n<p data-css=\"tve-u-1758046d6be\"><strong>[Recommended: read the original blog post “<a href=\"https:\/\/go.thegamedev.guru\/rt-global-illumination\">Unity ray-traced global illumination<\/a>” for proper interactive content]<\/strong><\/p>\n<p data-css=\"tve-u-1758046d6be\">Let’s get back to ray tracing with global illumination in Unity. Discover what global illumination is and choose the better fit for your game:<\/p>\n<ul>\n<li><strong>Baked GI<\/strong><\/li>\n<li><strong>Screen-space Raster GI<\/strong><\/li>\n<li><strong>Screen-Space Ray-traced GI<\/strong><\/li>\n<\/ul>\n<p><img decoding=\"async\" alt data-height=\"439\" data-id=\"9723\" data-init-height=\"608\" data-init-width=\"1080\" data-width=\"780\" height=\"338\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-3.gif\" title=\"Unity-Ray-Tracing-Global-Illumination-Thumbnail\" width=\"600\"><\/p>\n<p><strong>TABLE OF CONTENTS<\/strong><\/p>\n<p>1 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170145\">Can You Guess What’s Missing in This Scene?<\/a><\/p>\n<p>2 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170146\">What’s Unity Global Illumination?<\/a><\/p>\n<p>3 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170147\">Your Options for Global Illumination in Unity<\/a><\/p>\n<p> 3.1 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170148\">Unity Baked Global Illumination<\/a><\/p>\n<p> 3.2 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170149\">Unity Screen-Space Global Illumination (SSGI)<\/a><\/p>\n<p> 3.3 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170150\">Ray-Traced Global Illumination in Unity<\/a><\/p>\n<p>4 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170151\">The Performance Cost of Ray-Traced Global Illumination in Unity<\/a><\/p>\n<p>5 <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#t-1604169170152\">Next Steps<\/a><\/p>\n<h2 id=\"t-1604169170145\">Can You Guess What’s Missing in This Scene?<\/h2>\n<p>Take a second to have a look at the screenshot below.<\/p>\n<p>Can you guess what is this picture missing to be… visually “appealing”?<\/p>\n<p><img decoding=\"async\" alt data-height=\"439\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-width=\"780\" height=\"338\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-2.png\" width=\"600\"><\/p>\n<p>It’s looking either too bright or too dark. That’s not an easy thing to see in real life.<\/p>\n<p>Why?<\/p>\n<p>Because light bounces between surfaces.<\/p>\n<p>These bounces soften the “transitions” between bright and dark areas. And you don’t see that happening in the screenshot above. <\/p>\n<p>Now, let’s see something more realistic.<\/p>\n<p>Have a look below. Use <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi1\">the slider<\/a> to transition to a more “visually correct” scene:<\/p>\n<p data-css=\"tve-u-1757ff0e4e2\"><a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi1\"><strong>Is Global Illumination Overrated? (Answer: NO)<\/strong><\/a><\/p>\n<p><a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi1\"><img decoding=\"async\" height=\"338\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-3.png\" width=\"600\"><\/a><\/p>\n<p>What’s the difference?<\/p>\n<p>Global illumination (GI). To be more specific, indirect illumination.<\/p>\n<p>Let’s quickly explain how GI works.<\/p>\n<h2 id=\"t-1604169170146\">What’s Unity Global Illumination?<\/h2>\n<p>Like I said, light rays bounce off surfaces and lose energy in the process (e.g. brightness, a change in color, etc.). Eventually, light will reach your eyes from different surfaces.<\/p>\n<p>In graphics, we distinguish between:<\/p>\n<ul>\n<li><strong>Direct lighting<\/strong>: the sun light hits the floor and reflects into your eyes. That lets you see that specific fragment on the floor.<\/li>\n<li><strong>Indirect lighting<\/strong>: the sun light hits the floor, bounces to your hand watch <strong>and then<\/strong> bounces towards someone’s eyes. That person becomes temporarily stunned.<\/li>\n<\/ul>\n<p>The difference is that GI takes more bounces into account. Not just one.<\/p>\n<p>Direct lighting is easy and cheap to calculate. Indirect lighting, not so much.<\/p>\n<p>So, how do you do indirect lighting* in Unity?<\/p>\n<p>Here are your options.<\/p>\n<p><em>* I use the words indirect lighting and global illumination interchangeably. In theory, they’re not the same. But in practice, we treat them as if they were.<\/em><\/p>\n<h2 id=\"t-1604169170147\">Your Options for Global Illumination in Unity<\/h2>\n<p>Let’s build an ultra-simple scene to see and compare the different methods you have in Unity to do global illumination.<\/p>\n<p>Here’s the scene we are building:<\/p>\n<p><img decoding=\"async\" alt data-css=\"tve-u-1757ff684c6\" data-height=\"326\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-tcb-events=\"__TCB_EVENT_[{"t":"click","a":"thrive_zoom","config":{"id":"2075","size":"full"}}]_TNEVE_BCT__\" data-width=\"389\" height=\"504\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-4.png\" width=\"600\"><\/p>\n<p><em>Light Bounces Global Illumination Diagram<\/em><\/p>\n<p>First, take a deep breath and enjoy my drawing skills.<\/p>\n<p>Now, let’s explain it.<\/p>\n<p>A wall is covering\/occluding another wall, which in real-life would prevent light from reaching it.<\/p>\n<p>However, there’s a small gap below.<\/p>\n<p>This bottom gap will allow some sun rays to “escape” the big wall and reach the wall behind after these rays bounce off the floor.<\/p>\n<p>The diagram is clear, right?<\/p>\n<p>Here’s how our baseline (just direct lighting + shadows) looks in Unity.<\/p>\n<p><img decoding=\"async\" alt data-height=\"615\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-width=\"780\" height=\"473\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-5.png\" width=\"600\"><\/p>\n<p>Global Illumination Scenario<\/p>\n<p>We won’t use that angle. It’s hard to see the effect of indirect lighting later on.<\/p>\n<p>Here’s a better angle.<\/p>\n<p><img decoding=\"async\" alt data-height=\"615\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-width=\"780\" height=\"473\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-6.png\" width=\"600\"><\/p>\n<p>Global Illumination Baseline (No GI)<\/p>\n<p>The wall behind is quite dark.<\/p>\n<p>No global illumination means light is not bouncing. Our black shadow on that wall remains untouched with no secondary light rays coming in.<\/p>\n<p>Not what you want in your game. Nope.<\/p>\n<p>So let’s improve this scenario and add some GI with our first method: <strong>baked global illumination<\/strong>(Unity Lightmapper).<\/p>\n<h3 id=\"t-1604169170148\">Unity Baked Global Illumination<\/h3>\n<p>Baking global illumination is the <strong>cheapest way<\/strong> to do global illumination.<\/p>\n<p>We do all these expensive calculations offline (in the editor). That process produces textures that we later “<strong>paint on top<\/strong>” of our scene.<\/p>\n<p>It takes some effort to get the results you want with this method, as there are many settings to play with. And <strong>baking takes time<\/strong>.<\/p>\n<p>But once you get it right, it looks great.<\/p>\n<p>In fact, it’s probably the best-looking method out there to do (static) global illumination.<\/p>\n<p>The downsides?<\/p>\n<p>Well, it only works with static geometry.<\/p>\n<p>I mean, you can use light probes to add some indirect illumination to dynamic (moving) elements. But that also goes with many downsides.<\/p>\n<p>Anyway, let’s see how it looks.<\/p>\n<p>Use <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi2\">the slider<\/a> to see the evolution from no GI to baked GI.<\/p>\n<p><a href=\"https:\/\/www.gamasutra.com\/blogs\/RubenTorresBonet\/20201110\/373493\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi2\"><img decoding=\"async\" height=\"473\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-7.png\" width=\"600\"><\/a>Just like I promised you, it looks more… <em>correct<\/em>*.<\/p>\n<p><em>* You know what I mean. Not the simplified scene per se, but the indirect lighting.<\/em><\/p>\n<p>However, did you ever play an <em>interactive<\/em> game with just <em>static <\/em>elements?<\/p>\n<p>No, you say?<\/p>\n<p>That’s why we need more options.<\/p>\n<p>One is to use <a href=\"https:\/\/docs.unity3d.com\/Manual\/LightProbes.html\" target=\"_blank\" rel=\"noopener noreferrer\">light probes<\/a> together with <a href=\"https:\/\/docs.unity3d.com\/Manual\/lighting-window.html\" target=\"_blank\" rel=\"noopener noreferrer\">baked GI<\/a>. The issue with light probes is that you need many of them to have smooth indirect lighting transitions. And guess what? That’s going to break batching for good.<\/p>\n<p>Let’s consider instead something else: <strong>Screen-space (Raster) Global Illumination<\/strong>.<\/p>\n<h3 id=\"t-1604169170149\">Unity Screen-Space Global Illumination (SSGI)<\/h3>\n<p>The idea with SSGI is simple. It’s execution is not.<\/p>\n<p>We analyze the rendered frame (G-buffer) and guesstimate the way light should bounce between surfaces that are within that frame.<\/p>\n<p>Again, we don’t do that for the whole scene. Just for the current rendered image.<\/p>\n<p>Doing this effect in screen-space makes this option affordable in terms of performance.<\/p>\n<p>Use <a href=\"http:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi3\">the slider below<\/a> to find out what <em>SSGI <\/em>paints on top of our baseline.<\/p>\n<p data-css=\"tve-u-1757ff0e4e2\"><strong>Screen-Space Global Illumination (SSGI)<\/strong><\/p>\n<p><a href=\"https:\/\/www.gamasutra.com\/blogs\/RubenTorresBonet\/20201110\/373493\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi3\"><img decoding=\"async\" height=\"473\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-8.png\" width=\"600\"><\/a><\/p>\n<p>A small tint of red.<\/p>\n<p>Not much else.<\/p>\n<p>Here is in detail the indirect lighting that we are adding to our baseline:<\/p>\n<p><img decoding=\"async\" alt data-height=\"438\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-width=\"780\" height=\"337\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-9.png\" width=\"600\"><\/p>\n<p>Unity Global Illumination: Screen-Space Effect<\/p>\n<p>That’s a very shy effect. Quite different from baked GI, isn’t it?<\/p>\n<p>That’s one of the limitations of <em>SSGI<\/em>: accuracy. Two reasons for this:<\/p>\n<ul>\n<li>We have <strong>incomplete information<\/strong> (the G Buffer, information about our lights and that’s about it).<\/li>\n<li>We have a <strong>low performance budget<\/strong>: we need to keep this effect cheap.<\/li>\n<\/ul>\n<p>But hey, it works with dynamic elements. And in real-time <img loading=\"lazy\" decoding=\"async\" alt height=\"32\" role=\"img\" src=\"https:\/\/s.w.org\/images\/core\/emoji\/13.0.0\/svg\/1f642.svg\" width=\"32\"><\/p>\n<p>Can we do better?<\/p>\n<p>Yes!<\/p>\n<p>What if we used <strong>ray-tracing<\/strong> for global illumination?<\/p>\n<p>After all, with ray-tracing we have <strong>access to off-screen data<\/strong>. And that removes a limitation of this method.<\/p>\n<p>Let’s check out <strong>ray-traced SSGI<\/strong>.<\/p>\n<h3 id=\"t-1604169170150\">Ray-Traced Global Illumination in Unity<\/h3>\n<p>This is getting exciting.<\/p>\n<p>If your project is ray-tracing-ready, you just need to click a checkbox in your screen-space global illumination effect: <em>enable ray-tracing<\/em>.<\/p>\n<p>The result?<\/p>\n<p>Use <a href=\"http:\/\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi4\">the slider below<\/a> to discover it.<\/p>\n<p data-css=\"tve-u-1757ff0e4e2\"><strong>Ray-Traced Global Illumination<\/strong><\/p>\n<p><a href=\"https:\/\/www.gamasutra.com\/blogs\/RubenTorresBonet\/20201110\/373493\/thegamedev.guru\/unity-ray-tracing\/global-illumination\/#gi4\"><img decoding=\"async\" height=\"473\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-10.png\" width=\"600\"><\/a>Juicy.<\/p>\n<p>Here’s the singled-out effect that ray-tracing GI is adding to our baseline:<\/p>\n<p><img decoding=\"async\" alt data-height=\"444\" data-id=\"2075\" data-init-height=\"312\" data-init-width=\"300\" data-width=\"780\" height=\"341\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-11.png\" width=\"600\"><\/p>\n<p>Unity Global Illumination: Ray Traced Effect<\/p>\n<p>Indeed, ray-tracing gets you good-looking indirect lighting. And it works with <strong>dynamic elements<\/strong>… in real-time.<\/p>\n<p>Huge deal.<\/p>\n<p>The question is, <strong>can you really afford ray-traced global illumination<\/strong> in Unity?<\/p>\n<p>Let’s analyze the performance cost of these effects.<\/p>\n<h2 id=\"t-1604169170151\">The Performance Cost of Ray-Traced Global Illumination in Unity<\/h2>\n<p>Here are some quick tests I ran with:<\/p>\n<ul>\n<li><strong>CPU<\/strong>: AMD Ryzen 2700X<\/li>\n<li><strong>GPU<\/strong>: TITAN RTX beefy edition<\/li>\n<li><strong>Dataset<\/strong>: 3000 frames taken on the editor<\/li>\n<li><strong>Scene<\/strong>: HDRP template<\/li>\n<li data-css=\"tve-u-1758049c76b\"><strong>Versions<\/strong>: Unity 2020.2.0b7 + HDRP 10.0.1<\/li>\n<\/ul>\n<p><img decoding=\"async\" alt data-height=\"439\" data-id=\"9711\" data-init-height=\"770\" data-init-width=\"1368\" data-width=\"780\" height=\"338\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-12.png\" width=\"600\"><\/p>\n<p data-css=\"tve-u-1758049d5fa\">Here are the average frame times at full-HD resolution:<\/p>\n<ul>\n<li>Baked GI: 27.64ms<\/li>\n<li>Baked GI + SSGI (low quality): 28.19 ms<\/li>\n<li>Baked GI + SSGI (medium quality): 30.36 ms<\/li>\n<li>Baked GI + SSGI (high quality): 32.96 ms<\/li>\n<li>Baked GI + Ray-Traced SSGI (performance mode \u2014 low quality): 32.07 ms<\/li>\n<li>Baked GI + Ray-Traced SSGI (performance mode \u2014 medium quality): 32.88 ms<\/li>\n<li>Baked GI + Ray-Traced SSGI (performance mode \u2014 high quality): 34.81 ms<\/li>\n<li>Baked GI + Ray-Traced SSGI (quality mode): <strong>107.91 ms<\/strong> (ouch)<\/li>\n<\/ul>\n<p>And here are some of these numbers at 4K resolution:<\/p>\n<ul>\n<li>Baked GI: 106.21ms<\/li>\n<li>Baked GI + SSGI (medium quality): 114.56<\/li>\n<li>Baked GI + Ray-Traced SSGI (performance mode \u2014 medium quality): 119.77 ms<\/li>\n<li>Baked GI + Ray-Traced SSGI (quality mode): <strong>421 ms<\/strong> (OUCH)<\/li>\n<\/ul>\n<p data-css=\"tve-u-17580009ed7\"><em>Why did I take them all with baked GI, you might ask? Well, I removed the baked lightmaps and the entire scene broke for good. Like visually, all was pure white.<\/em><\/p>\n<p>Don’t take these times as absolute figures.<\/p>\n<p>After all, it’s a specific scene, a specific software\/hardware setup and within the editor.<\/p>\n<p>But you can compare the <strong>relative frame times <\/strong>and see how performance scales on this high-fidelity scene.<\/p>\n<p>You get the idea.<\/p>\n<p>Two interesting questions arise (and two subjective answers):<\/p>\n<ul>\n<li>Are we ready for 4K real-time ray-traced GI? Nope.<\/li>\n<li>Ok, and are we ready for 1080p real-time ray-traced GI? Yeah, maybe.<\/li>\n<\/ul>\n<p>It depends on your game.<\/p>\n<p>But if you put enough optimization effort into it, <strong>you can get real-time ray-tracing global illumination in. It’s feasible.<\/strong><\/p>\n<p>Just run it on performance mode at 1080p and you’ll be fine on most <em>NVIDIA 2000+<\/em> cards (and maybe even on the <em>NVIDIA 1000<\/em> series).<\/p>\n<p>And the importance of performance brings me to…<\/p>\n<p><a href=\"https:\/\/go.thegamedev.guru\/performance-checklist\" target=\"_blank\" rel=\"noopener noreferrer\"><img decoding=\"async\" alt data-css=\"tve-u-175800136b8\" data-height=\"197\" data-id=\"6536\" data-init-height=\"605\" data-init-width=\"747\" data-link-wrap=\"true\" data-width=\"243\" height=\"197\" loading=\"lazy\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-13.png\" width=\"243\"><\/a><\/p>\n<h2 id=\"t-1604169170152\">Next Steps<\/h2>\n<p>How much did you like real-time ray-traced global illumination?<\/p>\n<p>Well, you can get RTGI in your game if you <strong>make enough performance room<\/strong> (and <a href=\"https:\/\/thegamedev.guru\/unity-ray-tracing\/5-signs-you-need-ray-tracing\/\" target=\"_blank\" rel=\"noopener noreferrer\">all other Unity ray-tracing effects<\/a> as well).<\/p>\n<p>And <em>nothing better<\/em>* than my <a href=\"https:\/\/go.thegamedev.guru\/performance-checklist\" target=\"_blank\" rel=\"noopener noreferrer\">Unity Performance Optimization Checklist<\/a> for that.<\/p>\n<p><em>* <a href=\"https:\/\/go.thegamedev.guru\/consulting\" target=\"_blank\" rel=\"noopener noreferrer\">Unity performance consulting<\/a> is better (but not many can’t afford it).<\/em><\/p>\n<p>Till next time,<\/p>\n<p>Ruben<br \/>(The Gamedev Guru)<\/p>\n<\/p><\/div>\n<hr>\n<div class=\"hide-phone\">\n<h3>Related Jobs<\/h3>\n<div class=\"stories_item\">\n<div class=\"thumb\"><a href=\"https:\/\/jobs.gamasutra.com\/job\/senior-release-engineer-frisco-texas-34639\"><img decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-14.png\" alt=\"The Gearbox Entertainment Co.\" width=\"120\"><\/a><\/div>\n<\/p><\/div>\n<div class=\"stories_item\">\n<div class=\"thumb\"><a href=\"https:\/\/jobs.gamasutra.com\/job\/junior-programmer-cambridge-ma-cambridge-massachusetts-32982\"><img decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-15.png\" alt=\"Disbelief\" width=\"120\"><\/a><\/div>\n<\/p><\/div>\n<div class=\"stories_item\">\n<div class=\"thumb\"><a href=\"https:\/\/jobs.gamasutra.com\/job\/senior-programmer-chicago-chicago-illinois-32981\"><img decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-15.png\" alt=\"Disbelief\" width=\"120\"><\/a><\/div>\n<\/p><\/div>\n<div class=\"stories_item\">\n<div class=\"thumb\"><a href=\"https:\/\/jobs.gamasutra.com\/job\/junior-programmer-chicago-chicago-illinois-32983\"><img decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-15.png\" alt=\"Disbelief\" width=\"120\"><\/a><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<hr><\/div>\n<p> <!-- InstanceEndEditable --> <\/div>\n<p><!--end contentbox-->\n<\/div>\n<p><!--end span-16--> <\/div>\n<p> <br class=\"clear\"> <\/div>\n<p><!--end span-21--> <!--begin right sidebar--> <!--end right sidebar--> <!– <\/div>\n<p> Extra Div –> <!-- Beginning Sync AdSlot 21 for Ad unit Gamasutra\/\/consolepc ### size: [[8,2]] --> <!-- End AdSlot 21 --> <!-- Beginning Sync AdSlot 22 for Ad unit Gamasutra\/\/consolepc ### size: [[8,4]] --> <!-- End AdSlot 22 --> <!-- Beginning Sync AdSlot 23 for Ad unit Gamasutra\/\/consolepc ### size: [[4,4]] --> <!-- End AdSlot 23 --> <br class=\"clear\"><\/p><\/div>\n<p><!--end content-body-wrapper--> <\/div>\n<p><!--end container--><br \/>\n<!--begin footer--> <!--end footer--> <!-- SiteCatalyst code version: H.21.\nCopyright 1996-2010 Adobe, Inc. All Rights Reserved\nMore info available at http:\/\/www.omniture.com --> <a href=\"http:\/\/www.omniture.com\" title=\"Web Analytics\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sickgaming.net\/blog\/wp-content\/uploads\/2020\/11\/the-bright-side-of-ray-traced-global-illumination-4.gif\" height=\"1\" width=\"1\" border=\"0\" alt><\/a><!--\/DO NOT REMOVE\/--><br \/>\n<!-- End SiteCatalyst code version: H.21. --> <!-- Begin ADSNATIVE Code --> <!-- End ADSNATIVE Code --> <!--Begin Ad script for pixel --> <!--END Ad script for pixel --> <\/p>\n","protected":false},"excerpt":{"rendered":"<p><!– –> Gamasutra: Ruben Torres Bonet’s Blog – The Bright Side of Ray-Traced Global Illumination Informa Gamasutra is part of the Informa Tech Division of Informa PLC This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. 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