Challenging Roof

This is directed to builders that want a challenge. I have been told it CANNOT BE DONE, which is a no-no because I won't stop trying now.

I am building a 1890's Steamboat House at Jockey's Ridge 138,24,22. I think I have done a pretty good job on the house but saved the porch roof until almost the last. I am having trouble lining up the porch pieces to the right "angles" (rotation). If one is standing looking at the house - the left side of the porch roof is pretty good but the front pieces and the pieces on the right are all out of whack.
I know this roof is a prim burner.......but I have tried all kinds of shapes and for the roof to have the look I want it has to use all these pieces. But I am open to suggestions...

The textures are not lined up yet, for I want to get everything just right first. I have been working on this roof for weeks and have learned so much by doing it.....but watch......some really good builder will come in and tell me how to fix it in about five minutes! And that's ok by me.

I have looked at every riverboat house I can find in SL and no one has a roof like this one, and now I know why.

Cunundrum, I have been to your riverboat and it is so well done! You might want to look at this house.

Becca

Pictures?

I"m not about to take the time to go to your build in-world, sorry. But I could probably provide you with one of those "5-minute fix" answers you're looking for if I could see some good pictures of what you've got, and what you're trying to accomplish. I'm sure the same could be said for many here.

Don't believe whoever it was who told your build "cannot be done". There's absolutely nothing that cannot be done.

Chosen, understand and don't know why I didn't do that. Sorry. Will post pictures as soon as possible, which will be late tonight.

I couldnt even figure out where that was since there is nothing in places named Jockey's Ridge or your profile or the map.

Here are pictures of the roof. I did not get home to update my profile but will do it tonight. I hope these show what you need to see.

Try using sections of a cone? You might get away witrh as few as 5 prims that way. 2 straight ones along the sides of the poarch, and three cone sections for the curved parts.

That's the wonder of SL. It takes that statement and expands on it from RL.

Anywho, looking at the pictures, it's definitely possible. I cant quite tell, but it looks like that is a 'perfect circle' kinda shape (Half of one anyway). If this is true, you may be able to find a mega prim that works for this situation, since they work properly now. What you would want is a cylinder (I can't say the dimensions since I don't know your porch dimensions) that is hollowed, and then tapered as needed. Also path cut as needed

If that's not possible, you should be able to use a combination of cylinders and planes, with tapering, shearing, and path cut to get the effect you want.

I'm sorry that I can't give a more complete how-to, but that's about the best I can come up with at the moment.

ETA:: For me, cylinders and cones, and pyramids and boxes are interchangable words. I just say 'tapered cylinder' for a cone, etc.

Another possible way to go about it is to use cadroe murphy's ShapeGen tool. I find it invaluable for making any large round or spherical shapes.

Of course it can be done with a little math, which will be the easy part. The hard part will be challenging the SL rounding off of angles of rotation and pathcuts values to agree with the math. Basically, you have to find that perfect sized cube when pathcut and sized works out to the need of the build.

In the image I uploaded, it is 3 tapered cubes each the same size. At a glance, it looks like it would work, but it will not because each prim is 1mx4mx0.1m with a X=0.5 pathcut, and each prim is rotated 7.15 degrees to the next one. These dimensions will not work because the they need to be rotated 7.5 degrees in order to make a perfect corner section of the roof. It is just an exercise I did and chose arbitrary dimensions.

In some cases, it's easier to build the roof first and then the rest of the home!

Ceera - Tried the cones in the beginning for the curved corners and can't get the inside to fit to the curve.

Keira - will try a mega prim.

This roof has been two to twenty pieces of varying shapes, sizes and even a sculpie.
The inside curve is actually the outside part of a cylinder stretched sideways as far as it will go(the porch floor itself).

I really need someone to tell me how to make those pieces adjust to the correct angle for the slant on the roof and to fit. When I get one side level with the rest of the roof the opposite side is too high or too low. It has to do with adjusting along degrees both horizontal and vertical at the same time...........I think it is beyond my expertise. My brain just can't function in 3D.

I'm an accountant in RL. Everything has to balance, ie. line up.......or it drives me nuts.

Thanks for your help so far.

Would it help if you had a version of the shingles texture that had some curve to it? Then put the rectilinear version on the straight side pieces, and the curved ones on the tapered pieces.

Another possible solution is a sculpted prim already textured. Using http://sculptyspace.com/ to export as Obj then use http://www.unwrap3d.com along with Photoshop to apply texture.

Math of some sort is going to be involved here, though you don't have to do it with scripting.

If you can work out the shape of one panel (the trapesium shape Dytska is talking about) and get it in place, and you can put an "axis" prim at the center of the circle of the roof, you can accurately position the other panels by doing the following:

Link the panel to the axis prim, making sure the axis is root.
Shift drag a copy of the linkset and ctrl-z to put it back where the original is.
Use the rotation arrows in the build window (the z rotation) to rotate the linkset around so that the new panel lines up with the old.
Repeat.

When you've got all your panels, unlink them all and delete the axis prims.

Note that you have to use the arrows in the edit window, if you use the rotate circles on the linkset, it will rotate around the center of the linkset rather than the center of the root prim.

Four words: Cadroe Murphy's Cadroe Lathe.

Set the segments to 1 and the sides to maybe 15. Rez away and viola.

http://www.slexchange.com/modules.php?name=Marketplace&MerchantID=56642

A

I like Seifert's method. I made a trapezium as follows:

x=1.175, y= 0.1, z=5.0
x-taper = 0.56

This gets a trapezium very close to something that works for 7.5-degree rotations which works out when making a 90-degree turn.

I then lined it up with a 1/2 cylinder (your floor) that was 8m in diameter.

Then I made a little 0.1x0.1x0.1 cube at the same coordinates as the floor. I made the floor hollow so I can see the cube.

Next, link the trapezium to the cube. Then, rotate the cube by the numbers so you rotate both pieces for the right roof slant you like - I used a 15-degree slant.

Unlink the cube and the trapezium and move the trapezium so it looks best against the floor. Set the rotation of the cube back to 0,0,0 and relink the trapezium to the cube.

Make a copy of the cube/trapezium link set, place it in the same position, rotate it by the numbers 7.5 degrees. Repeat as needed!

With this method, I did see some gaps, caused by rounding errors I guess. Also, this only works if the 1/2 cylinder floor is circular and not an ellipse.

for your adjustments, I know this may sound overly simplistic but I didnt know about it for the longest time, try using the local ruler instead of world? You mention about having to adjust the angles horizontal and vertical, I found the local ruler made life heaps easier when fiddling with roof angles. I am sure you already know about it. But thats all I have lol

Good looking house/boat btw

Rebecca, I am sending you the really old freebie version of a tool I used to make a very similar roof, you can also find a commericial, updated version of the same tool here:

http://www.slexchange.com/modules.php?name=Marketplace&file=item&ItemID=223298


It's going to solve your problem lickity split.

Rebecca, it looks like you've already gotten some pretty good advice. I'll throw in some additional tips as well. A structure like that is actually quite easy to make. Some people have suggested using automated tools, like Cadroe's lathe maker, which would work, but wouldn't actually teach you anything about building. I'd rather talk about a method you can learn from. Here's one way you can make this kind of shape by hand, rather quickly.

First, lets talk about the number of panels you should use for the half-circle part. I'd suggest you go with 12. At highest level of detail, cylinders in SL have 24 sides (not counting the top and bottom, just the sides). That's what we're all used to thinking of as a "cylinder". So for half a circle, 12 is a match. If you want your shape to look smoother, you can use more, but that would be kind of a waste. 12 will work just fine.

Second, let's talk work flow. Basically, what we're going to do is build a 12-panel half cylinder. Then we're going to taper all the panels, so the top of the cylinder becomes like a u-shaped edge. Next we'll skew the tops inward toward the center of the cylinder. After that, we'll stretch each panel inward toward the center to create slope of the roof. Next, we'll taper each panel in the other direction to eliminate overlap. And finally, we'll cut an hollow each piece, so the roof's top and bottom surfaces are parallel, rather than being level on the bottom, and only sloped on the top.

OK, let's get started. Since we know we're using 12 sections, the only little bit of math we need to do is really easy. A half circle is 180 degrees. Divide that by 12 sections, and you get 15 degrees for each one. So now you know that if panel A is rotated at zero degrees on Z, panel B should be at 15 degrees, Panel C should be at 30 degrees, etc.

Rez your first panel. Make it as thin as you possibly can on Y, and whatever width you like on X. With the ruler in Local mode, shift-drag the panel to leave a copy behind, and move it sideways on local X by half the prim's own width, and snap it there to the ruler. The center of the original should now be precisely aligned with the edge of the copy. Now, rotate the original by 15 degrees on Z, and then move it again along local X by half its own width, and snap it to the ruler. The edge of the original should at this point be precisely aligned with the edge of the copy, the two panels forming 15-degree V-shape. Shift-drag the original again, and repeat the process 10 more times to form a 12-panel 180 degree arc.

Link the arc, and scale it to whatever size is the outer edge of your roof. Then adjust the height of the panels to be the height of the roof. All that remains now is to create the slope, and trim off the resulting overlap in the panels.

To begin to form the slope, taper the panels all the way on Y. This will turn the top of the arc into a thin edge, rather than a flat surface. Now, skew the top of each piece all the way on Y, toward the center of the arc. The positive or negative direction of the skew will depend on which direction you rotated the panels when you first made the arc.

Now, before we move on to complete the slope, unlink the arc. We're about to use the reference ruler, which doesn't work on linked parts.

Stretch one of the panels on local Y, inward toward the center of the arc. Stretch it whatever distance is required to make its inner edge touch the outer edge of your rooftop deck railing. Once you've got the Y size right, keep the prim selected and press shift-G (with chat closed). This will set the ruler to reference mode, with the selected prim as the unit base. You can now stretch each of the other pieces inward on their local Y axes, and snap them to the ruler to make them the exact same size as the referenced panel.

You now have a roof with the correct arc shape, and with the correct size and slope, but there's a slight problem. You've got corners sticking out all over the places since the panels aren't yet tapered on X. Finding the right amount of X-taper will take a little trial and error. Taper any two neighboring panels by the same amount, and see how it looks. If you've still got overlap, increase the amount. If you've got a gap, decrease it. When you find the right magic number, apply it to all the panels, and your roof will top will be perfect.

Sometimes, you'll find that there is no perfect number. There's either a little bit of overlap, or a little bit of a gap. That's OK; don't panic. It's just a symptom of the fact that tapering in SL is limited to two decimals. It's not uncommon at all for the number you want to fall somewhere in between two hundredths. In that case, you can solve the problem by staggering the numbers. Let's say, for example, that .55 is too big, and .54 is too small. Well, assign .55 to the first, third, fifth, seventh, ninth, and eleventh prim, and then assign .54 to the second, fourth, sixth, eighth, tenth, and twelfth prim. The resulting average will then be .545, and the prims will appear to be perfectly aligned, no overlap, no gaps.

At this point we're just about done. Only one thing remains. The bottom of the roof is level instead of sloped. You can leave it that way if you want, but if you'd rather have the roof's bottom be sloped, simply hollow the panels, and cut them each by 75%. You'll end up with some V-shaped grooves along the edges where the panels meet, but those will be easy to hide with texturing.

If you'd rather not have the grooves, you can use a different construction method. It'll be a little harder, though. Basically, instead of tapering the cubes on Y, you'd rotate them on local X, then taper them on Y, and stretch them on X to eliminate the gaps. That method is a lot lengthier to explain, which is why I opted to go with the other one here. But the results are cleaner. Based on what you've probably learned from this post, I'm sure you'll be able to figure out how to make that method work if you want to.

The first time you do either method, it will probably take you about an hour or so to make that kind of a shape without error. But once you've gotten used to the technique, it only takes a couple of minutes.

Using an automated tool, if you choose to go that route, is not significantly faster, just so you know. Sometimes, it's actually even slower. The only real benefits of the automation are that it requires a little less manual labor, and a lot less thought.

I hope this has been helpful. Happy building.

First let me thank all of you for your wonderful advice, instructions and encouragement. I have renewed energy to tackle and finish the house.

I logged in last night to find presents! Generous examples of different prims that can be used. And I have waiting another from Pie! Plus offers of help. SL residents are the best!

Chosen - thank you for your instructions. I have printed them out and am excited to try step by step when I get inworld. And yes, I do learn by doing and much prefer manual over tools, but use tools after I have mastered and understood what the tool is doing. (ie. accounting software over the old general ledger books)