Brick Arches

[madmax]

Hi,

Great program and thanks for making it available!.

I'm using it to create custom-printable brickpaper for an OO/HO scale UK historical model railway. I'm quite interested in creating a viaduct section with accurate scale girder and brick-arch bridges out of card and paper.

I've managed to easily create English Header Bond which I will post an example separately, however I wonder if the program could be made to print out viaduct/bridge brick arches which can either be used as a texture for other 3d modellers or printed and cut out to use in conjunction with brickpaper by card modellers like myself.

This would involve printing out several semicircles of bricks (called "rings"), one inside the other. It would need to use some sort of sine/cosine function to rotate the bricks in sequence around the arc of the brick arch and also take care of brick bonding overlap.

Typical UK viaduct arches would involve a 5 or 6-ring (layer) brick arch and all would use "brick-on-edge", i.e the standard UK brick of 9 inches by 4 inches by 3 inches stood on it's 3 inch "end" and with the 4 inch side aligned with the radius of the arc. so...

[MrSparkle]

Hi Max!

I thought about your problem and I think you're right. This feature will be added to the new Bricks'n'Tiles version. Although, in 3d computer graphics brick arches are done in a very different way, creating a arch texture with an alpha mask could also be useful for handcrafted textures.

Usually, I use the existing method to create textures for brick arches that are already present in the 3d model's geometry. I use the texture coordinates of the geometry to project the same texture onto differently shaped arches, thus, I don't have to create different textures for each model.



The same way, the same texture is applied to different arches in the above picture, it could also be used for gothic and roman arches at the same time, because the shape is given by the actual 3d model.

In Bricks'n'Tiles there could be a little editor to create your own shapes by adjusting some parameters like Width, Height, Radius...

Any other ideas?

Christian

[madmax]

Hi, sorry for the delay. Been building up a replacement laptop

The only thing I can think of is that brick arches are usually multiple-ring unlike some of the example stone arches. Hence this means addressing the complexity of bonding (brick overlap) around the perimeter of an arc

Brick arches used to be built by creating a wooden "former" or arch support which was then shuttered-over with planking. The bricks would be laid over that with the correct bonding.

So setting the bonding right around a curved edge might perhaps be complex?. Breaking the bond wouldn't look good. i.e. having two bricks perfectly aligned one above the other.

Also arches would be made of brick-on-edge since what you have is effectively a tunnel created by "wrapping" a layer of single-brick "walls" around a curved surface. What one sees at the visible arch end is the "brick ends". Not sure if I've explained that well but I'm using a metaphor from 3d design (I hope!)

Anyway, what I mean are that the size of the bricks would differ from any seen with the usual "side-on" bonding view where either a full brick is seen (9 inches long by 3 inches high) or a half-brick overlap or header course (4 inches x 3 inches approx)

Those museum photo links of viaduct and bridge construction I emailed would probably give more of an idea.

Also. As far as English (engineering) bond goes (alternate layers of header and stretcher courses) I have noticed that the way bricks must have been made frequently leads to the header ends being a different colour from the side faces. I've noticed a distinct "striping" effect on some engineering brickwork where the header course is dark blue but the stretcher course is mixed purple/red/blue. The point arising from this is that if you add code to generate English bond then a different brick selection might be needed in each course.

Here is the best picture I can find at the moment illustrating the striped effect often seen
http://www.15c.co.uk/Leicester/Leicester-07.htm

Hope this helps!

[Boingo the Clown]

I am also in need of a way to make brick or stone arches for some game textures I want to make.