"Bald Eagle" <cre### [at] netscapenet> wrote: > Because my kid was watching a Bob Ross video: > > https://towardsdatascience.com/bot-ross-teaching-a-computer-to-paint-f5a9c9ef908 > > :) After a quick read though, I think the Bot should have watch more shows :)
"Bald Eagle" <cre### [at] netscapenet> wrote: I've done the VRand_ON_Box (RandSeed) awhile ago for my MeshTree project along with VRand_ON_Cone,VRand_IN_Cone, VRand_ON_Cylinder, VRand_IN_Cylinder I used them to place the end points of a binary tree. When I looked back on them I found that the Cone marcos use a cone with a base pov unit from <0,0,0,> the end point 1 unit in opposite direction 1 with the base radius 1 and the other radius 0 and you had a choice of 3 directions to place it (x,y,z). The On_Cone also had the OPEN option. The cylinder macro has the same basic lay out. They work great for making trees but I don't know if they have an even distribution. Here they are copied from the modified rand.inc I use. //a random point ON a square box {-1, 1} #macro VRand_On_Box(R)// LR added #local V=<0,0,0>; #local a=int(rand(R)*6); #switch (a) #case(0)#local V=<-1,rand(R)*2-1,rand(R)*2-1>; #break #case(1)#local V=<1,rand(R)*2-1,rand(R)*2-1>; #break #case(2)#local V=<rand(R)*2-1,-1,rand(R)*2-1>; #break #case(3)#local V=<rand(R)*2-1,1,rand(R)*2-1>; #break #case(4)#local V=<rand(R)*2-1,rand(R)*2-1,-1>; #break #case(5)#local V=<rand(R)*2-1,rand(R)*2-1,1>; #break #end (V) #end //a random point ON a Cylinder from -1 to 1 in the D direction // radius=1 // if O open cylinder // D=1 +y direction // D=2 +x direction // D=3 +z direction #macro VRand_On_Cyl(D,O,R)// LR added #local Theta = 2*pi*rand(R); #local V=<0,0,0>; #local H=rand(R)*2-1; #local S=1; // radius #if(O) #local Hv=1; #else #local Hv=.95; #end #if (H>Hv) #local S=rand(R);#local H=1; #end #if (H<-Hv) #local S=rand(R);#local H=0; #end #if (D=1)#local V= <H,cos(Theta)*S,sin(Theta)*S>; #end #if (D=2)#local V= <cos(Theta)*S,H,sin(Theta)*S>; #end #if (D=3)#local V= <cos(Theta)*S,sin(Theta)*S,H>; #end (V) #end //a random point IN a Cylinder from -1 to 1 in the D direction // D=1 +y direction // D=2 +x direction // D=3 +z direction #macro VRand_In_Cyl(D,R)// LR added #local Theta = 2*pi*rand(R); #local V=<0,0,0>; #local H=rand(R)*2-1; #local S=rand(R); #if (D=1)#local V= <H,cos(Theta)*S,sin(Theta)*S>; #end #if (D=2)#local V= <cos(Theta)*S,H,sin(Theta)*S>; #end #if (D=3)#local V= <cos(Theta)*S,sin(Theta)*S,H>; #end (V) #end //a random point ON a Cone from -1,1 to 1,0 in the D direction // more values in the lower part // if O open Cone // D=1 +x direction // D=2 +y direction // D=3 +z direction #macro VRand_On_Cone(D,O,RS)// LR added #local Rt=rand(RS); #local Rv=Rt*Rt; #local Theta = 2*pi*rand(RS); #local V=<0,0,0>; #local H=Rv*2-1; #local S=1-(H+1)/2; #if(H<-.95 & O=0) #local S=rand(RS); #local H=-1;#end #if (D=1)#local V= <H,cos(Theta)*S,sin(Theta)*S>; #end #if (D=2)#local V= <cos(Theta)*S,H,sin(Theta)*S>; #end #if (D=3)#local V= <cos(Theta)*S,sin(Theta)*S,H>; #end (V) #end //a random point IN a Cone from -1,1 to 1,0 in the D direction // more values in the lower part // D=1 +y direction // D=2 +x direction // D=3 +z direction #macro VRand_In_Cone(D,RS)// LR added #local Rt=rand(RS); #local Rv=Rt*Rt; #local Theta = 2*pi*rand(RS); #local V=<0,0,0>; #local H=Rv*2-1; #local S=1-(H+1)/2; #local S=S*rand(RS); #if (D=1)#local V= <H,cos(Theta)*S,sin(Theta)*S>; #end #if (D=2)#local V= <cos(Theta)*S,H,sin(Theta)*S>; #end #if (D=3)#local V= <cos(Theta)*S,sin(Theta)*S,H>; #end (V) #end
"Kenneth" <kdw### [at] gmailcom> wrote: > "Kenneth" <kdw### [at] gmail
com> wrote: > > > Voila! Well, discounting the mathematical magic that would probably be required. > > ;-) > > I do see the main problem though, and it's a big one: How to correlate an > oddly-shaped total 'area' of triangles on the TEXTURE map (certainly not a 1X1 > ratio area, and with an oddly-shaped perimeter) to the HF itself, which *is* a > 1X1 ratio. It would be a strange scaling problem indeed. > > :-( Well serendipity and synchronicity strike again: I was looking for some info to better explain the meaning of the core inequality in the polygon test, and I found a video by Sebastian Lague https://www.youtube.com/watch?v=HYAgJN3x4GA with this link in the comment section: https://chrischoy.github.io/research/barycentric-coordinate-for-mesh-sampling/
Thomas de Groot <tho### [at] degrootorg> wrote: > You should do something about those midges.... ;-) I took a cue from Robert and set the fireflies loose on them. :P
"Robert McGregor" <rob### [at] mcgregorfineartcom> wrote: > > I don't think I've ever tried posting a video here before but I'm attaching a > short MP4 clip of the animated engine media, hopefully it works. Your final ship is really gorgeous, and the animation of the engine 'ion exhaust' looks great! It's a nice and sophisticated use of media. Btw, thanks for the description of your ship's surface texture; I had originally thought that you had used one of POV-ray's newer 'pavement' patterns (perhaps that is part of the mix), but your averaging(?) of simple box and rectangle shapes/images makes perfect sense. I look forward to experimenting with that technique. Your work has really paid off! It's inspiring. [As is usual with videos uploaded here-- at least through the newsgroups' web portal-- the downloaded animation doesn't play in Windows Media Player, even though it should. So I've learned to use a different media player app to play it. I don't think the problem is with the added .mp4 suffix here, whether left as-is or removed; it seems that the upload/download process adds 'something' to the file, or makes it different somehow. On my own Win 7 computer, I can play my own animations in WMP; but when I upload them here, then download them, they don't play. Weird.]
"Bald Eagle" <cre### [at] netscapenet> wrote: > That's looking like a Firefly-class transport ship! +1 :D Thanks! Now that you mention it, there is a *slight* resemblance to the Serenity. But she's more curvaceous :) Thomas de Groot <tho### [at] degroot
org> wrote: > VERY good, sir! I am awed by the way you just seem to shake this > casually from your (admittedly ample) sleeve. "Mr" <nomail@nomail> wrote: > yummy eye candy! Thanks Thomas and Maurice, this is a fun project, I'm glad you like it! I don't think I've ever tried posting a video here before but I'm attaching a short MP4 clip of the animated engine media, hopefully it works.
"Kenneth" <kdw### [at] gmailcom> wrote: > Voila! Well, discounting the mathematical magic that would probably be required. > ;-) I do see the main problem though, and it's a big one: How to correlate an oddly-shaped total 'area' of triangles on the TEXTURE map (certainly not a 1X1 ratio area, and with an oddly-shaped perimeter) to the HF itself, which *is* a 1X1 ratio. It would be a strange scaling problem indeed. :-(