Author Archives: bartwronski

Checkerboard rendering, rotated anti-aliasing and grid frequencies

Posted on May 14, 2018

This post is inspired by three interesting statements or questions that I heard and are interconnected by non-obvious theory: First was regarding so called checkerboard rendering (example1 example2) – what is advantage of using it? After all it’s the same as … Continue reading →

Posted in Code / Graphics | Tagged antialiasing, fourier, frequency domain, sampling, signal theory, supersampling | 4 Comments

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

Posted on October 22, 2017

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 →

Posted in Code / Graphics | Tagged diagrams, mathematica, mathematics, tech writing, tools | 3 Comments

Separable disk-like depth of field

Posted on August 6, 2017

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 →

Posted in Code / Graphics | Tagged bokeh, depth of field, dof, far cry 4, Gaussian, maths, photography, poisson, postprocessing, separable, witcher 2 | 2 Comments

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

Posted on April 13, 2017

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 →

Posted in Code / Graphics | Tagged cone, culling, geometry, graphics, ideas, lighting, mathematica, mathematics, occlussion, programming, sphere, spot, visibility | 5 Comments

Small float formats – R11G11B10F precision

Posted on April 2, 2017

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 →

Posted in Code / Graphics | Tagged float, floating point, floats, graphics, mathematica, mathematics, noise, programming, quantization, rendering | 6 Comments

Dithering part three – real world 2D quantization dithering

Posted on October 30, 2016

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 →

Posted in Code / Graphics | Tagged bayer, blue noise, dithering, fourier, graphics, graphics programming, interleaved gradient noise, mathematica, mathematics, maths, noise, programming, sampling | 5 Comments

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

Posted on October 30, 2016

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 →

Posted in Code / Graphics | Tagged blue noise, dithering, golden ratio, graphics, graphics programming, low discrepancy, noise, programming | 9 Comments