Author Archives: bartwronski

Tech and scientific writing – graphics, diagram and graph creation tools

Few days ago, I asked a question on twitter: https://twitter.com/BartWronsk/status/919618905319997440 “What is industry/academic standard for diagrams in tech writing? PowerPoint/GoogleDocs diagrams? Dedicated tool like Visio/Dia? Procedural? I usually use first, but far from satisfied…For proc tried SVG,JS,Graphviz,even Mathematica, but results … Continue reading

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Separable disk-like depth of field

This is a short note accompanying shadertoy: https://www.shadertoy.com/view/lsBBWy . It is direct implementation of “Circularly symmetric convolution and lens blur” by Olli Niemitalo (no innovation on my side, just a toy implementation) and got inspired by Kleber Garcia’s Siggraph 2017 presentation “Circular … Continue reading

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Cull that cone! Improved cone/spotlight visibility tests for tiled and clustered lighting

In this blog post, I will present some common spotlight culling techniques and propose one small improvement that is able to correct results of cheap, tiled / clustered culling on the CPU/GPU with almost negligible ALU cost. If you know … Continue reading

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Small float formats – R11G11B10F precision

While this post is not yet dithering related, it is in a way a part of my series about dithering. You can check index of all parts here or check the previous part. I will talk here about use of … Continue reading

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Dithering part three – real world 2D quantization dithering

In previous two parts of this blog post mini-series I described basic uses mentioned blue noise definition, referenced/presented 2 techniques of generating blue noise and one of many general purpose high-frequency low-discrepancy sampling sequences. In this post, we will look … Continue reading

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Dithering part two – golden ratio sequence, blue noise and highpass-and-remap

In previous part of the mini-series I covered dithering definition and how dithering changes error characteristics of simple 1D quantization and functions. In this part I will try to look at what blue noise is, but first wanted to have a … Continue reading

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Dithering part one – simple quantization

Introduction First part of this mini-series will focus on more theoretical side of dithering -some history and applying it for 1D signals and to quantization. I will try to do some frequency analysis of errors of quantization and how dithering … Continue reading

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