Panorama reversed when mapped to wall

[Craig Bagley]

I'm working in AC9, and trying to create a proper window view.

When I map a panorama as a texture to a circular wall, it's reversed.

On a straight wall, I seem to be able to control it by drawing the wall right to left instead of left to right. That trick doesn't seem to work on a curved wall.

Odd behaviour: Take a straight wall where the panorama is set correctly, then curve it ("Curve Edge"), and the panorama flips.

The panorama always seems to flip the wrong way on a curved wall.

I read an earlier post about manipulating the material as follows: Material Settings>Lightworks Rendering Engine>Lightworks Shader Settings>Texture Space> Graphisoft Replicate>Angle: 180 degrees. This change doesn't seem to do anything in my case.

I'm sure this has been solved somewhere, and any help would be appreciated.

[Dwight]

That's a recognized bug that would fix itself if you upgrade, but there could still be anomalies in LightWorks interpretation since Archicad itself has only basic mapping formulae.

My advice is to make all the possible material map permutations and use the appropriate one for your situation.

[Dwight]

SHAMELESS PLUG:
My book has an extensive article on making cycloramas. Including how to make it not show shade.

[Brett Brown]

Hi Dwight,I have your book. But I can't find what I am looking for. I have been told the easiest way to have a movable background (as a single photo)is to have the background photo as a texture on a wall. What I can't get right is the relation between the pixel size of the photo,the texture size and then the height and length of the wall to get just one texture and not repeating. Is there any standard formula or rules for doing this?

[Dwight]

I will send you another book since yours is obviously missing pages 154 - 155.

YOU NEED:

1: a photo assemblage.
2: the photo's horizontal aspect in degrees. NOT "lens angle" invariably expressed as the diagonal field of view. The book shows how to use a degree marked pan head to precisely assemble 180 or 360 degrees in a panorama - angles that correspond to Archicad's need to split 360 degree walls into 180 degree pieces.

3: BASIC GEOMETRY:
http://www.321know.com/geo612x4.htm
The easiest way is to make two images that total 360 degrees and map them separately to each of the complimentary 180 degree walls. The width of EACH image therefore equals CIRCUMFERENCE/2.

CIRCUMFERENCE /PI = DIAMETER OF CIRCLE

There you go… and Robert becomes the relative who stopped sending $5 in a card every Christmas once you stopped sending a thank you note.

The resulting photo height is your wall height - adjust the wall altitude by eye to match the image horizon with your Archicad camera view.

3D Alignment places the texture where you want it to start.

Some advice:
-You don't need very many pixels to background a flythru. The images in my book [and my previous example] were done with a lousy cellphone at different times of day and with different weather. Nobody noticed after i wielded my photoshop wizardry.

-the formula doesn't tell you anything about appropriate absolute sizes. In my experience a circle of around 100m in diameter is going to work without convergence. This requires an image of around 157m to make 180 degrees of image.

- add plenty of fake sky to the top of the panorama - make the cyclorama high to avoid ever seeing over the top of it.

-don't worry about shadow, cut a windo into your cyclorama to let the sun hit your model.

Other tricks are in that article, too, especially how to keep shade from affecting your cyclorama.

[Brett Brown]

Thanks for that Dwight but my pages aren't missing.I just want a photo taken from the site put on a straight wall to use as a background to a camera view looking outside from a room, and as a moveable background for a rendered perspective. Using the photo as a background image doesn't work as it is two hard to move house relative to background.Hence putting it on a wall. Hope you can understand this and is this the easiest way or some other way? Thanks

[Dwight]

I was joking about pages missing. Some books got upside down pages, but none had missing.

So, you don't want a panorama. A flat wall increases the difficulty because it doesn't have a self-completion aspect. With a panorama, you know when the circle is complete.

Placing such an image would be subjective, except for the horizon line. If you DO know the camera angle, place the flat wall with image subtending the comparable angle on a circle radiating from the Archicad camera viewpoint - that should be close enough. Scale as with cyclorama.

As for the number of pixels required for the background… you'd follow the Pragmatist's and the Perfectionist's Rules of Thumb on pages 110 and 111 that relate the texture map size to the final rendering size.

In my cyclorama work, positioning the image was subjective except that we knew a certain prominent neighbor would be right in front of the balcony so everything flowed from that alignment.