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About haki

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  • Birthday 06/25/1988

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  • Name
    Hristo Arabadzhiyski
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    The Netherlands
  1. Propagating point creation with VEX

    Hey folks, back with an update here, I took care of the curve framing: Thanks to Entagma's Parallel Transport tutorial I understood the core concept here. I adapted it to my curves generator. I tried 2-3 alternatives, including the slideframe() function and the dihedral()*v0. Seems I got the best result by crossing vectors only. The slideframe and the dihedral seemed somewhat off, probably because I didn't do something right. Here's the file if you wanna give it try: rand_dir_propagating_points_3.hiplc
  2. Propagating point creation with VEX

    Eureka! (No need for point arrays after all...) So, from what I originally intended to be a grass generator... it will be a multi-purpose generator (including the effect on hair that electrocution has according to popular cartoon depictions) Still to figure out a way to control the up angle at every sample... and to orient the points correctly based on the starting points (polyframe the prims I guess...) [Edit] - With some finetuning below: rand_dir_propagating_points_2.hiplc
  3. Propagating point creation with VEX

    Ta-da! I got the point arrays exactly in the correct order for the point number pattern I was getting. Alright, it's going to be smooth sailing from here on… (doing a little dance) Wait, what!? Addprim didn't do what you imagined? Documentation, here I come.
  4. Propagating point creation with VEX

    Cheers, @Librarian I hope you can find some use for it. I attached the current WIP file there. I can't wrap my head around how to gain manual control over the rand vector for each sample yet.
  5. Propagating point creation with VEX

    A quick update: rand_dir_propagating_points.hiplc
  6. Propagating point creation with VEX

    Thanks, Thomas! Ok. It seems I'm missing something here to understand why it always gets (0,0,0). On sample 1 it doesn't seem to get (0,0,0). Let me see. Maybe my comment's complete nonsense, so back to the drawing board: It seems like this does what I've sketched above: Now onto figuring out how to gain some degree of manual control over the random angle for each sample... Cheers!
  7. Propagating point creation with VEX

    Cheers, Thomas! That explains some of the confusion I had. And, you're right I was probably overthinking it. Thanks for the base script! I didn't write that in the post above, but I intended to later randomize the up vector direction for every new point and thus get a non-linear propagating pattern. I want to achieve a sort of (and I suspect that's not the right term here) parent-child behavior between every point and the next in line (something like tentacles constructed by points propagating in random directions). That's the reason why (in my head at least), calculating a new up by subtracting current_pos from new_pos and setting that at every sample is important. Except, and this is probably going to seem totally dumb... at sample 2 it falls apart. Up is no longer pointing where I'd expect it to. I bet this has something to do with the last line current_pos = point(0, "P", new_point); rand_dir_propagating_points.hiplc vector up = @up; vector current_pos = @P; vector new_pos = 0; int samples = chi("samples"); float offset = chf("offset"); for(int i = 0; i < samples; i++){ new_pos += current_pos + up * offset; int new_point = addpoint(0, new_pos); up = normalize(new_pos-current_pos); setpointattrib(0, "up", new_point, up, "set"); current_pos = point(0, "P", new_point); } It appears at sample 2, the up direction is pointing away from the world origin, and not away from the points at sample 1. I feel like I'm missing something so basic...
  8. LATEST WIP UPDATE: ---------------------------------------------------------------------------------------------------------------------------------------------------- Hi folks, How would you go about adding points in a propagating manner in VEX. Here's what I mean: - Start with several incoming base points, each with an up vector. - For each one, add a new point somewhere along its up vector. - Calculate a new up vector by subtracting base positions from new point positions and setting the new point up vector to the result - Add the next new point somewhere along the previous point's up vector So, I called it propagating, because every next point in part defines the following. I think I'm on the right track here, but my gut's telling me I'm missing something. I'm stuck. Here's what I got: vector up = point(0, "up", @ptnum); vector currentPos = point(0, "P", @ptnum); vector newPos = {0,0,0}; int pts[]; for(int i=0; i<@numelem; i++) { append(pts,i); } int iteration = chi("iteration"); for(int j=0; j<=iteration-1; j++){ newPos = currentPos+up; int newPoint = addpoint(0, newPos); setpointattrib(0, "up", len(pts)+j, normalize(newPos), "set"); currentPos = point(0, "P", len(pts)+j); up = normalize(newPos-currentPos); currentPos = newPos; } Where do you think I'm wrong here. What would you do? Cheers!