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diff --git a/Shaders/hg_sdf.cginc b/Shaders/hg_sdf.cginc deleted file mode 100644 index b1de0b0..0000000 --- a/Shaders/hg_sdf.cginc +++ /dev/null @@ -1,187 +0,0 @@ -#ifndef __HG_SDF__ -#define __HG_SDF__ - -#include "pema99.cginc" - -//////////////////////////////////////////////////////////////// -// -// HG_SDF -// -// GLSL LIBRARY FOR BUILDING SIGNED DISTANCE BOUNDS -// -// version 2021-07-28 -// -// Check https://mercury.sexy/hg_sdf for updates -// and usage examples. Send feedback to spheretracing@mercury.sexy. -// -// Brought to you by MERCURY https://mercury.sexy/ -// -// -// -// Released dual-licensed under -// Creative Commons Attribution-NonCommercial (CC BY-NC) -// or -// MIT License -// at your choice. -// -// SPDX-License-Identifier: MIT OR CC-BY-NC-4.0 -// -// ///// -// -// CC-BY-NC-4.0 -// https://creatifloatommons.org/licenses/by-nc/4.0/legalcode -// https://creatifloatommons.org/licenses/by-nc/4.0/ -// -// ///// -// -// MIT License -// -// Copyright (c) 2011-2021 Mercury Demogroup -// -// Permission is hereby granted, free of charge, to any person obtaining a copy -// of this software and associated documentation files (the "Software"), to deal -// in the Software without restriction, including without limitation the rights -// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -// copies of the Software, and to permit persons to whom the Software is -// furnished to do so, subject to the following conditions: -// -// The above copyright notice and this permission notice shall be included in all -// copies or substantial portions of the Software. -// -// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -// SOFTWARE. -// -// ///// -// -//////////////////////////////////////////////////////////////// -// -// How to use this: -// -// 1. Build some system to #include glsl files in each other. -// Include this one at the very start. Or just paste everywhere. -// 2. Build a sphere tracer. See those papers: -// * "Sphere Tracing" https://link.springer.com/article/10.1007%2Fs003710050084 -// * "Enhanced Sphere Tracing" http://diglib.eg.org/handle/10.2312/stag.20141233.001-008 -// * "Improved Ray Casting of Procedural Distance Bounds" https://www.bibsonomy.org/bibtex/258e85442234c3ace18ba4d89de94e57d -// The Raymnarching Toolbox Thread on pouet can be helpful as well -// http://www.pouet.net/topic.php?which=7931&page=1 -// and contains links to many more resources. -// 3. Use the tools in this library to build your distance bound f(). -// 4. ??? -// 5. Win a compo. -// -// (6. Buy us a beer or a good vodka or something, if you like.) -// -//////////////////////////////////////////////////////////////// -// -// Table of Contents: -// -// * Helper functions and macros -// * Collection of some primitive objects -// * Domain Manipulation operators -// * Object combination operators -// -//////////////////////////////////////////////////////////////// -// -// Why use this? -// -// The point of this lib is that everything is structured according -// to patterns that we ended up using when building geometry. -// It makes it more easy to write code that is reusable and that somebody -// else can actually understand. Especially code on Shadertoy (which seems -// to be what everybody else is looking at for "inspiration") tends to be -// really ugly. So we were forced to do something about the situation and -// release this lib ;) -// -// Everything in here can probably be done in some better way. -// Please experiment. We'd love some feedback, especially if you -// use it in a scene production. -// -// The main patterns for building geometry this way are: -// * Stay Lipschitz continuous. That means: don't have any distance -// gradient larger than 1. Try to be as close to 1 as possible - -// Distances are euclidean distances, don't fudge around. -// Underestimating distances will happen. That's why calling -// it a "distance bound" is more correct. Don't ever multiply -// distances by some value to "fix" a Lipschitz continuity -// violation. The invariant is: each fSomething() function returns -// a correct distance bound. -// * Use very few primitives and combine them as building blocks -// using combine opertors that preserve the invariant. -// * Multiply objects by repeating the domain (space). -// If you are using a loop inside your distance function, you are -// probably doing it wrong (or you are building boring fractals). -// * At right-angle intersections between objects, build a new local -// coordinate system from the two distances to combine them in -// interesting ways. -// * As usual, there are always times when it is best to not follow -// specific patterns. -// -//////////////////////////////////////////////////////////////// -// -// FAQ -// -// Q: Why is there no sphere tracing code in this lib? -// A: Because our system is way too complex and always changing. -// This is the constant part. Also we'd like everyone to -// explore for themselves. -// -// Q: This does not work when I paste it into Shadertoy!!!! -// A: Yes. It is GLSL, not GLSL ES. We like real OpenGL -// because it has way more features and is more likely -// to work compared to browser-based WebGL. We recommend -// you consider using OpenGL for your productions. Most -// of this can be ported easily though. -// -// Q: How do I material? -// A: We recommend something like this: -// Write a material ID, the distance and the local coordinate -// p into some global variables whenever an object's distance is -// smaller than the stored distance. Then, at the end, evaluate -// the material to get color, roughness, etc., and do the shading. -// -// Q: I found an error. Or I made some function that would fit in -// in this lib. Or I have some suggestion. -// A: Awesome! Drop us a mail at spheretracing@mercury.sexy. -// -// Q: Why is this not on github? -// A: Because we were too lazy. If we get bugged about it enough, -// we'll do it. -// -// Q: Your license sucks for me. -// A: Oh. What should we change it to? -// -// Q: I have trouble understanding what is going on with my distances. -// A: Some visualization of the distance field helps. Try drawing a -// plane that you can sweep through your scene with some color -// representation of the distance field at each point and/or iso -// lines at regular intervals. Visualizing the length of the -// gradient (or better: how much it deviates from being equal to 1) -// is immensely helpful for understanding which parts of the -// distance field are broken. -// -//////////////////////////////////////////////////////////////// - -#define PI 3.14159265 - -// Repeat around the origin by a fixed angle. -// For easier use, num of repetitions is use to specify the angle. -float pModPolar(inout float2 p, float repetitions) { - float angle = 2*PI/repetitions; - float a = atan2(p.y, p.x) + angle/2.; - float r = length(p); - float c = floor(a/angle); - a = glsl_mod(a,angle) - angle/2.; - p = float2(cos(a), sin(a))*r; - // For an odd number of repetitions, fix cell index of the cell in -x direction - // (cell index would be e.g. -5 and 5 in the two halves of the cell): - if (abs(c) >= (repetitions/2)) c = abs(c); - return c; -} - -#endif // __HG_SDF__ |