Roofing

Hi Axel5616,

This is a great question and happens to be the topic of what I'm working on right now. I have the goal of developing a reasonably easy construction workflow to get a good looking result for a roof line, roof plates and the wall fascia that go together to make an aesthetically pleasing construction.

Since I have to draw up some sketches to show the details let me answer your question in words first so you can get started on the thought process. In roof construction the key variables are called run, rise and slope. Run is the horizontal distance the roof covers, rise is the vertical distance the roof goes up at the end of the rise, and the slope is the angle of the roof. the tangent function of the slope angle is the ratio of the rise divided by the run: tan(slope) = rise/run.

For example if the rise is 3 blocks over a run of 6 blocks tan(slope) = 3/6 = 0.5, the actual slope angle is arctan(0.5) = 26.56505 degrees where the arctan function converts the slope into an angle. In the US we use a notation of 6/12 to describe this, since for odd reasons we continue to use an antiquated measurement system based on 12 inches to the foot.

On your phone you probably have a nice calculator to figure out the angle for various ratios you might want to use using the arctan or atan or tan-1 key. You will need this number to do construction. I'll show a table in my next post with pictures.

Now we get to the first detail that makes a difference in getting a smooth workflow for roof construction in Rising World. As you will notice, most of the ratios you might want to try out are almost always irrational numbers that go on forever. The question is, how accurate do you have to be? When you are in the block positioning mode there is an option to press C on your keyboard and then on the option wheel you can set the precision of the angle setting over a wide range. I have found that a setting of 0.1degree always works to get a pleasing result and a setting of 1 degree usually works over short runs.

If you have messed around with trying to do roof construction in Rising World you have probably encountered the block pivot problem. This is the issue where you want to align and position the roof plates at the right angle and place so you get the roof plates to line up with the roof fascia. The roof fascia is the triangular piece that is placed on the rise line that fits under the roof. In the diagrams I am going make, all this will be clear. The key to relatively easy placement is to develop two appropriate ridge line pieces that provide a clean look to the roof and good pivot points. There is also the issue of figuring out whether the roof extends beyond the building frame edge. This is usually done with roofs to provide better rain protection for the building sides.

By the way, in the next installment I will discuss how to get the first roof plate block on the ridgeline piece aligned correctly so that the image of the roof shingles goes down correctly, a tricky little detail... Once that is done properly on each side of the roof that side of the roof can be done lickity split.

As a preview, these three images of a test construction show some of the concepts: first image is the outside view, second image is the inside view showing beams, third view shows the block pieces which are useful for constructing roofs of various sizes for a given run rise ratio including the triangular roof fascia piece. Not included here are the ridgeline pieces .

Just an addendum, the length of the A frame roof is the hypotenuse of the run rise triangle, hyp = (run² + rise²)^1/2.

In the case of an A frame of run = 3, rise = 6 then hyp = (3² + 6²)^1/2 = 6.708. a length of 6.7 will probably work. As you know there still is the problem of finding the angle of tilt. which is the method i just described. You can use a cut and try method by tilting the roof block off the end of the foundation to get an angle that looks ok.

Following up, here's a quick outline of roof specifications in various formats. By the way I think for large structures with significant angle as in the A frame that the angles need to be specified to the second decimal place. I think this can be fixed by intentional overlap of structures to conceal gaps.

Next we have two looks from outside and inside of an A-frame concept using a 16 block base for the A-frame. The first image shows the view toward the entrance of the front facade and how you might tile the texture for a no-window situation. The second view shows a view from the inside toward the door to show a concept for the timber framing at the front. This would provide for structure for a loft above the first floor.

The second image shows the triangular ridge cap beam cross-section. The ridge cap beam can be used to tile the roof plates downward for designs that have significant eave extensions, but that of course requires mountain goat abilities...

Finally, there are 3 images of a 16 block practice design, from the front, inside and on the side to show how things go together.

This has been a fun little project to get familiar with the Rising World build mechanics.

Reasonably easy, huh?

Quote from Axel5616

Thanks so much for the detailed response. The pictures of framing are very helpful. I'll have to study the math some, a bit over my head I'm afraid.

Honestly, i skip the math and just do it freestyle. I start with the basic outlines of the building, then add a single post at the middle of the building. Then i attach a fully stretched beam to this middle post and use a 30 - 45 degree angle (depending on the width of the building). I extend the beam with more beams, the last one shorter than the max of 5, until it reaches the walls of the building. If it happens that between the beam and the wall is still some space, i just use some more blocks on top of the wall to close the gap (i shrink them of course, so the wall is not going through the roof).

Once the first A-frame is done, you can just go from there by attaching a beam to the already existing one and maneuvr it into place. That process is way faster and easier (for me) than to do calculation in advance. I hope one day Red will implement a tool, like the measuring tape, that will make it easier to calculate angles but until then this is my way and im usually very satisfied with the outcome.

Hi Axel! I'm glad you can find some use and ideas out of this for your builds. The beauty of 12/6 is that it easy to come up with wall pieces to build the facades because the rise:run ratio is always 2:1. So installing windows and doors at odd places for crazy design reasons is not hard, since the fill pieces are all easy to make on the fly. I haven't got to stairs to the loft yet, but I'm anticipating that it won't be so bad. I'll keep you updated on how it goes, and good luck with your project!

Hi Avanar! Thanks for your comments, I appreciate them and I get where you are coming from. Your point about using 60^o is well taken. Your approach takes a simple angle use for the slope and replaces the irrational part in the rise with a simple cut and try vertical frame block - well done. I know about the limitation to 5 block extensions in the real world so I have settled on a 4 block vertical frame piece and variants to handle vertical frame needs. Certainly Axel might find it easier to use your method going forward.

My problems are really two fold - one is that I've only been doing this for a couple of days, so for an old fogey like me, learning the somewhat tricky build interface has been a chore. Not that it's bad, I think Red has done a great job of adapting Unity's build methods to a nice set of mechanics, just tricky.

My second problem is that I like a challenge and I've been around engineers way too much over my life. So I'm trying to figure out how to make a 12/6 A Frame with a loft. All in an effort to learning the build mechanics in a way that is transferable from creative mode. You comments were very helpful to me to expand my views.