konstantin magnus

I also find the decision unfavorable. But once you reverse the winding order the polygon will face positive axis directions.

In my opinion this particular tutorial series is way too complicated and long-winded for beginners. In case you are just getting started with procedural modeling I would rather recommend Kim Goossens Youtube-Channel and the Gametutor website.

Would anyone know a simple formula to very roughly approximate the sun path (or rather sun vector)?

Do you know about the polyexpand node?

Hi Justin, in order to fill a voxel field with image pixels put this code in a volumewrangle after a volume node: vector bbox = relbbox(0, v@P); vector map = colormap(chs('image'), bbox.x, bbox.y); f@density = luminance(map);

Hi philpappas, to extract main features of your curve you could first measure its curvature with the new measure SOP or by calculating the dot product of your tangents (see attachment). Afterwards a derivation of the curvature might be useful to only keep "break points" that are important to the visual appearance of your curve. I just would not know how to calculate this though. curve_curvature.hiplc

Hi Niels, I tried the torus route as suggested on twitter: float r_torus = chf('radius_torus'); float r_tube = chf('radius_tube'); float freq = chf('frequency'); v@pos_rest = v@P; vector bbox = relbbox(0, v@P) * M_TWO_PI; v@P.x = (r_torus + r_tube * cos(bbox.x)) * cos(bbox.z); v@P.y = (r_torus + r_tube * cos(bbox.x)) * sin(bbox.z); v@P.z = r_tube * sin(bbox.x); v@Cd = noise(v@P * vector(freq)); v@P = v@pos_rest; seamless_noise.hip

Yes, you could take the convertline SOP, promote the wave attribute to primitives and delete by this attribute. @DévinOdforce: I attached an example. dashed_curves_prims.hiplc

Let a sine wave run across your curves, set the dash length with frequency, animate by adding time and define the gap size by comparing the value with a custom threshold. float u = vertexprimindex(0, @vtxnum) / float(primvertexcount(0, @primnum)); float u_length = u * primintrinsic(0, 'measuredperimeter', @primnum); float u_anim = (u_length + @Time * chf('speed')); int waves = sin(u_anim * M_PI * chf('frequency')) < chf('gaps'); v@Cd = hsvtorgb( set(u, 1.0, 1.0) ) * waves; If you want your dashed line to be static just replace u_anim inside the sin() function by u_length. dashed_curves.hiplc

On a grid-node just right-click in order to switch the expression language to Python and use this:

Great idea @f1480187, creating the rotation matrices from the cage lines is definitely cleaner!

Thanks for your help @tmdag. I had to invert the rotation matrix. So its: vector freq = chv('frequency'); vector dir = normalize( minpos(1, v@P) - v@P ); vector rect = normalize( cross(v@N, dir) ); vector nml = normalize( cross(dir, rect) ); matrix3 rot = set(dir, nml, rect); float deform = noise(v@P * invert(rot) * freq); v@P += v@N * deform * 0.05;

I have made some progress in making the wrinkles run towards the outer edges. Unfortunately i still get lots of warping issues that I can't quite explain. Ideally I want all folds to run in a parallel manner towards their nearest outer edge. This is the code I am currently using: vector pos_b = minpos(1, v@P); vector dir = normalize(pos_b - v@P); vector rect = cross(v@N, dir); vector nml = cross(dir, rect); matrix3 rot = set(dir, nml, rect); vector freq = {8, 1, 40}; vector pos = rot * v@P * freq; float deform = noise(pos); v@P += v@N * deform * 0.05; folds_wrinkles_2.hiplc

One question remains: How would one scale radial vectors so a circle turns into an n-gon?

Well, there wouldnt been a single line without your brain ; )