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Found 31 results

  1. hyperbolic tiling

    A shot in the dark here, but has anyone done any hyperbolic tiling in Houdini? The structure is really beautiful but the math is extremely complex, for me at least. Would love to see if anyone has tackled something like this in Houdini
  2. Peter Claes - Youtube channel

    Hi all, As some of you may know I have recently started a youtube channel where I am sharing some techniques, setups and tips. My goal is to first cover some of the fundamental tools/setups and then build more elaborate setups. I wanted to share this with the odforce community too as this community will always have a special place in my heart :). Thank you for watching & have fun learning! The channel: https://www.youtube.com/channel/UCZMPkkgnAFghvffxaTh6CsA My first video:
  3. I wrote an article that is probably only of interest for the .1% It is a crash introduction to HDK, C++ and the mesh laplacian. https://mbaadsgaard.com/portfolio/laplacian-eigenvector-plugin-for-houdini/ Feedback is, of course, also welcome
  4. Finding the Min/Max values in a field?

    I am trying to figure out how to get the converse of a field, mathematically. I am attempting to blur a Cd field in using a Gas Blur microsolver. I have some mixed results, but I want to get some finer control over the radius, namely that I want it to blur more as it slows down. I have used the gas analysis microsolver to get the speed field by taking the length of the velocity, but I can't figure out how to get larger values to be in the lower speed areas. Obviously I would love to use a fit to invert the values, but I am struggling with an elegant way to get the minimum and maximum values for a given field. I could easily just do a loop in a wrangle and get the min/max values that way, but that is going to be extremely slow as this is a very large, dense simulation. Is there a simple way I can get the min/max values in a field so I can use fit(@speed, min, max, max, min) in a Gas Field Wrangle node to get the converse of my field?
  5. clifford torus effect

    Hi every one, I kinda have an idea to create, though not a good one, but wanted to show it here and ask how would you guys go about this effect in Houdini, let me know ur thoughts https://codepen.io/znah/pen/dKdoKW?editors=0010
  6. The Book of Shaders in Houdini Vex

    Hi People! this has a lot of potentials I think sources ---- https://github.com/JosephFiola/BookofShadersHoudiniVex https://thebookofshaders.com Joseph "While Houdini does support GLSL code to render shaders into the viewport, I have not implemented this yet. For now these examples are only visible in the render view using the Ray Tracing render engine." We have examples for 2 and 5 chapters .....if you plug inline-code in CD on Point Vop, you can see everything..and its easy to manipulate.. I am interested to know some process ( Just what to change ) and appreciate help with this. converting rest of some chapters like patterns for example to inline code https://thebookofshaders.com/09/ https://thebookofshaders.com/08/ Thanx
  7. Geodesics in Heat

    Hi everyone! I've made an illustration video-tutorial about the Heat Method application to point clouds by Keenan Crane et al, Yang Liu et al and others.
  8. Hi, As the title says, how, mathematically speaking, can I set points on a curve based on its curvature? What do I need to learn to do this? Trigonometry and derivatives? Thank you
  9. hey guys. simple question which I do not hold the answer to. I have a switch and I want it to switch input number every 50th frame going between 0 and 1. so example would be that for the first 50 frames the active switch value is 0 and then on frame 51 it goes to 1, hold that for 50 frames and then turns back to 0. I need this to be a procedural expression if possible rather than key framing it. Thanks
  10. Hi, I compute the velocity on an animated point and I copy a geometry on it which inherits the velocity but of course is not correct as every point now has the exact same vector. How can I realign the existing velocity in the geometry using vex without having to recompute it? I have attached an example hip. orientvelocity.hipnc
  11. Hello guys, I'm currently a Computer Graphics bachelor student, we are learning CGI but also, Mathematics, Python and C++ some people are very proficient with all these 3 while I'm very proficient in CG but not very strong in these field. I'm very motivated to learn and go deep into these 3 field but I would also like to be efficient in the way I will learn it. ( learning all the mathematics is unfortunately not possible. ) So I would like to know what is your best advice to start learning mathematics and programming to become an FX-TD, based on your own experience or on some experience from other people? Do FX-TD always use programming in the task they are asked for? Any advice, any experience is very much welcome and it would help me a lot.
  12. Didn't you think of these fluid solvers? How are they made? How to build them? We will talk about the theory of the process of building fluid solvers in my new course understanding fluid solvers on MIX Training. This is volume 1, volume 2 soon! http://mixtrn.com/course/understanding-fluid-solvers-volume-1/
  13. A simple question perhaps - I am getting my head around the nodes representing "blend modes" in a shader: One of the most useful blend modes in Photoshop, Mari etc. is Overlay. How do you guys recreate "Overlay" in a node graph where you only have Add, Subtract, Multiply or Divide?
  14. Hi all, I've started putting an asset together which allows me to create multiple 'threads' from a single line, then effect them as if they are fraying/weaving. I'm quite happy with it, however my approach doesn't lend itself well to anything other than straight lines, and I'd like to apply it to more/multiple complex curves - so that it follows their contours exactly. At the moment it does 'work', however it distorts the original curve quite a lot, which I'd like to avoid. Could anyone suggest a way for me to adapt my current VOP setup to calculate the trigonometry per curve? Or an alternative to using the 'wireU' attrib? Or alternatively, if there is a different approach I should be taking all-together? any pointers in right direction would be much appreciated .hip attached - Thanks in advance! (N.B. This setup is loosely based on a thread I originally found here on odforce some time ago - but I cannot for the life of me find it now, so a hat tip goes to OP if reading.) thread_tool_asset_003.hip
  15. Pluralsight is proud to offer three new courses... one covering intermediate level ocean shot development, a second covering the development of visual effects for Unreal Engine, and another covering the fundamental math concepts that are pivotal to working within Houdini. Below is a bit about each course and a link where you can check out the course overviews. Houdini: Intermediate Ocean FX by Andreas Giesen Link: www.pluralsight.com/courses/houdini-intermediate-ocean-fx In this course, you'll learn how to setup a procedural ocean and do a flip fluid simulation for a traveling boat in choppy waters. First, you'll discover how to use the ocean spectrum to create an infinite ocean. Next, you'll add the boat, do a flip simulation for a specific area with high detail, and add whitewater and mist. Finally, you'll extend the simulated area and set-up the shaders to render all the layers. When you're finished with this Houdini 16 course, you'll not only have an ocean rendered with a high detail fluid simulation, but you'll also have a workflow on how to master your own ocean and fluid challenges in the future. (Software required: Houdini 16.) Houdini VFX for Games by Andreas Glad Link: www.pluralsight.com/courses/houdini-vfx-games Have you ever sat down in Unreal Engine to create an effect, and not had a clue where to start? In this course, you'll start from the very beginning by creating the textures for your sprites. Next, you'll create debris in a way that allows you to use it repeatedly and uniquely. Finally, you'll add all the extras to really sell the effect, like decals, camera shake, and a shockwave. When you are finished with this course, not only will you have gained a deeper understanding of timing and the importance of telling a story with the effect, but you'll have planted the seed for future endeavors into proceduralism. (Software required: Houdini 15 and up, Photoshop and Unreal Engine 4.) Practical Houdini Math Tips by Beau Garcia Link: www.pluralsight.com/courses/houdini-practical-math-tips In this course, you will learn the math that drives Houdini effects production. First, you'll learn about Sines and Cosines. Next, you will explore the concept of Vectors. Finally, you'll finish the course learning about Matrices, Quaternions, Dot Products, and Cross Products. When you're finished with this Houdini course, you'll have a solid foundation in the math skills needed to produce high end visual effects. (Software required: Houdini 15 and up.) Thanks, and as always, I'd love to hear your feedback on these courses so we can continue to improve! Learn more about SideFX and Pluralsight: www.pluralsight.com/sidefx
  16. This tutorial goes over from start to finish the creation of a rudimentary fence asset that can easily be expanded upon. This is an introductory lecture on procedural modeling in Houdini I gave at Drexel University's SIGGRAPH chapter as a Junior Animation & FX major. Let me know if you have any questions, enjoy! Link To Demo File: drive.google.com/open?id=0B--RBrg9u--oWkNDU2ZUYnFpUjQ Link to Documented File: drive.google.com/open?id=0B--RBrg9u--odEhVYnluaFRGeGs
  17. Hi I want to randomly select two points from a geo input in a VEX wrangle, so far I have this: int _selectedPts[]; _selectedPts[0] = rand(@numpt); _selectedPts[1] = rand(@numpt); setattrib(geoself(),"point", "Cd", _selectedPts[0], 0, {1,0,0}, "set"); setattrib(geoself(),"point", "Cd", _selectedPts[1], 0, {1,0,0}, "set"); I searched on the VEX docs but every random function I found could only return float numbers, but I need integer numbers. How can I solve this?
  18. Hi I need an array wich stores a range of numbers, starting at zero and ending at @numpt (total amount of points in a geometry). Is there a fast way to do this apart from filling the array in a for loop? Thanks
  19. Hi ladies and gentlemen, boys and girls, I have a job to create a kaleidoscope animation. I'm just learning how a Kaleidoscope works in real life and time is limited. Has anyone ever worked on such a project and can give tips on how to get started and maybe some math behind how it works? I've attached a video I found that has this effect created by buck (starting at about 16 seconds in). Any help here would be much appreciated really. Thanks in advance. Sherwin Williams - Kaleidoscope-SD.mp4
  20. Frame of Reference _ Matrix

    Hi EVERYONE : Maybe this tutorial is not very short, watch it completely, i am sure that you find new stuff about matrix and you will learn new technique .Hope you find it useful !!! Hossam Aldin Alaliwi more training here : www.hossamfx.org
  21. Frame of Reference _ Matrix Tutorial

    if you have some problems with matrix, how it work, how to use , HOPE this tutorial will help .Hossam Aldin Alaliwi full tutorial here : hossamfx.org/math-in-houdini-vol2/ cheers!
  22. Spherical Coordinates

    Hello, I'm trying to replicate the same deformation as seen in the gif below. After some research I believe it's got something to do with Spherical Coordinates? I implemented the formula from this site which is: radius = sqrt(x^2 + y^2 + z^2) polar = arccos(z/radius) azimuthal = atan2(y, x) x = radius * sin(polar) * cos(azimuthal) y = radius * sin(polar) * sin(azimuthal) z = radius * cos(polar) But this results in some pinching of the cube at both poles, so maybe this isn't right, or I haven't done it correctly? Has any one got any experience with something like this? Any help would be really appreciated. Thank you sphere_deform.hip
  23. Attribute Reorient Node Tutorial

    Hello community : i created this short tutorial on how to use the reorient attribute node in houdini and also i showed how it is work, it is some math matrix stuff, hope you find it helpful and hope you like it : Note : this training will give you nice idea of using the Matrix in Houdini , .
  24. If I want to transform a velocity vector by a matrix4, do I just multiply it by the transpose(inverse(matrix4))? maybe I need to extract the scale from the matrix and multiply the velocity by that as well? Cross posting from https://www.sidefx.com/forum/topic/45863/ in case more people will see it here
  25. Math in Houdini FX VOL 1 Tutorials

    http://www.hossamfx.org/math-in-houdini/ Description: This training demonstrates the big role of Math in creating visual effects and controlling the simulation behavior in Houdini FX animation software. I will cover many of the most popular math topics in computer graphics and I will show you how to apply these concepts inside Houdini with some cool projects. I will focus on what we need to know from math for using in VFX without diving into complex mathematical details as this training is not about pure math. I will show you how the Dot product can be used with the Flip Fluid, and how to create windy curves using the Cross product, and how the Matrices can determine the velocity and store the rotation data.....and many other features of using Math in Houdini. Lesson plan 1. Introduction to vectors – What is the vectors and, why we need it in math and physic and CG ?. 2. Dot product definition – Introduction to Dot product equation in math: input, return, formula, spatial situation, deficiency of Dot product . 3. Dot product and angle calculate – Simple example in Houdini for using Dot product to calculate angle between two geometry. 4. Dot product inside flip fluid 01 – Create custom force attribute for controlling fluid behavior. 5. Dot product inside flip fluid 02 – Solving deficiency in Dot product and final behavior test. 6. Cross Product definition – Introduction to Cross product equation: what we need to know about Cross Product for using in CG, and what we don't need ?. 7. Cross Product and particles 01 – Aiming dynamic force in particles by Cross product for creating windy curves (like frozen animation film). 8. Cross Product and particles 02 – Adding randomizing vector to Cross product and update vector every 10 frames. 9. Cross Product and particles 03 – Add amplitude to Cross Product direction vector and final simulation. 10. Cross Product and particles 04 – Reorient all curves by one direction using For each SOP. 11. Cross Product and particles 05 – Emitting particles from curves and creating advanced time manipulating expressions with time shift node . 12. Matrix 01 – Rotate the attributes by Matrix to save the orientation after rotation. 13. Matrix 02 – Generate Matrix using Align Vex Node and create attributes to store reorientation Matrix in, Create advanced reorient system using Matrices and For Each. 14. Matrix 03 – Without Matrix it will need a code of 20 lines to do this effect, Modify particles velocity vector by rotation matrix. 15. Sine Function 01 – What is the sine function parts in math. 16. Sine Function 02 – Adding two sine wave to simple grid. 17. Decay Solver 01 – What is the decay and what are the types of decay in life. 18. Decay Solver 02 – Creating decay solver simulation in Houdini to decay physical attributes like fluid's temperature, viscosity and cloth's wetness….etc. 19. Manipulate Rang[0-1] – Creating 10 different complex shapes from simple point number expression. ِAll Content With Project Files .
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