[Question] How to use a picture or HDR as a background for Outdoor scenes?

[cadviz]

Hi;

For Architectural Visualization, I have a question…

How to use (a picture OR HDR) as a background to fill the far empty environment surrounding my house in a 3D outdoor scene?

Thanks in Advance

4shared - free file sharing and storage

[Nawrot]

It all depends if you want use flat image or cubemap.

If you have 360deg render or panorama, mask sky with alpha, make cylinder (without top/bottom) then add that panorama as transparent/masked material. Use sky blueprint for sky. Add some fog on top.

For stars/nebulas or some rendered sky. You should use sphere with cubemap, and reflection material that reflects your texture.

Keywords for feeding google: “unreal skybox”,
you will get many results from ancient skybox techniques to ut3 sphere mapped, to newest way with reflection and procedurally generated “skyboxes” that are not boxes anymore.

If you precise what kind of “skybox” you need i may give more detailed info.

[cadviz]

Hi Nawrot Thanks or your help
You had delivered rich information which is not easy for a Beginner UE4 user (like me)… So I will take it one by one, and you may correct me (if you don’t mind)
01.

@Nawrot;173802

It all depends if you want use flat image or cubemap.

In fact I would like to be able to use both

02.

If you have 360deg render or panorama, mask sky with alpha,

I may guess this is a Photoshop issue… Right !!?

03.

make cylinder (without top/bottom)

This is a 3D application job (3ds Max, Maya, & Blender)…?
Btw; I am using 3ds Max

04.

then add that panorama as transparent/masked material. Use sky blueprint for sky. Add some fog on top.

An UE4 issue ?

05.

For stars/nebulas or some rendered sky. You should use sphere with cubemap,

Where to find the (sphere with cubemap) inside UE4?

06.

and reflection material that reflects your texture.

Shall this material be for the Sphere OR my objects in the scene…?

07.

Keywords for feeding google: “unreal skybox”,…
If you precise what kind of “skybox” you need i may give more detailed info.

For what purpose Skyboxs should be used…?
well; since I know nothing about skyboxs inside UE4… then I shall do with your googling advice, moreover; I have to check the UE4 documentation…
Thanks again &
Best Regards

[Nawrot]

First: “Skybox” in unreal 1999 (or quake) was used for fake sky. It was literally a box with 6 textures. Since then everything that imitates sky is usually called “skybox”, there are no boxes in sky anymore it is just name for all in the sky.

This tutorial is about creating cubemap sky: Unreal Engine 4 Tutorial: Skybox Creation !OUTDATED! - YouTube

It uses procedurally generated stars, but you can render clouds, or take real clouds texture. However i am not sure how to make that spherical projection out of normal texture/photo. This should be used for outer area of skybox.

You can use that cubemap texture method, or sky blueprint from example content.

When you have outer regions of skybox complete, you need something closer. Like horizon. For that you can do cylinder or ring in 3d max, remove top and bottom surfaces and flip all faces so they face inside. Then you need to UV map that. A bit better way is making sphere and cutting out south half, then most of north part from top. You should get a bit curvy ring. Some people say its better than normal ring, but i do not see difference. For that ring you need some panorama texture, do alpha mask (its not issue with photoshop, its way of creating transparent textures in ue). Mask sky out, then make transparent material in ue.

And finally you can add few touches to skybox like pictures of city scape or distant trees. That should be done with plane (one sided 2d box) and transparent material just like for ring above but showing some houses etc.

For even more detail you add some low poly static meshes, like nearest houses, trees (use speed tree here), cars etc.

2. No it is not photoshop issue, you want 360deg panorama for texture for that horizon ring in skybox

3. cylinder/or ring with flipped faces, so they face inside. Or that one ring cut out of sphere.

4. For horizon you need to mask/remove parts of texture. For eg. you have skyscrapers in horizon, you want to mask all sky between them so your sky is visible, not one from photo. So mask sky with alpha then create material in ue4 that makes masked area invisible.

5. watch tutorial about cubemap sky. You need to create all that yourself.

6. That material is for most outer sky part, ie. sphere with cubemap. Again flip faces on sphere so they face inside of ball.

7. Again “skybox” is term for everything you use for fake sky. And it is not a box anymore, but it was in 1999.

[cadviz]

@Nawrot;174278

First: “Skybox” in unreal 1999 (or quake) was used for fake sky. It was literally a box with 6 textures. Since then everything that imitates sky is usually called “skybox”, there are no boxes in sky anymore it is just name for all in the sky.

This tutorial is about creating cubemap sky: https://www.youtube.com/watch?v=OjOhQ1DeQ8s

It uses procedurally generated stars, but you can render clouds, or take real clouds texture. However i am not sure how to make that spherical projection out of normal texture/photo. This should be used for outer area of skybox.

You can use that cubemap texture method, or sky blueprint from example content.

When you have outer regions of skybox complete, you need something closer. Like horizon. For that you can do cylinder or ring in 3d max, remove top and bottom surfaces and flip all faces so they face inside. Then you need to UV map that. A bit better way is making sphere and cutting out south half, then most of north part from top. You should get a bit curvy ring. Some people say its better than normal ring, but i do not see difference. For that ring you need some panorama texture, do alpha mask (its not issue with photoshop, its way of creating transparent textures in ue). Mask sky out, then make transparent material in ue.

And finally you can add few touches to skybox like pictures of city scape or distant trees. That should be done with plane (one sided 2d box) and transparent material just like for ring above but showing some houses etc.

For even more detail you add some low poly static meshes, like nearest houses, trees (use speed tree here), cars etc.

2. No it is not photoshop issue, you want 360deg panorama for texture for that horizon ring in skybox

3. cylinder/or ring with flipped faces, so they face inside. Or that one ring cut out of sphere.

4. For horizon you need to mask/remove parts of texture. For eg. you have skyscrapers in horizon, you want to mask all sky between them so your sky is visible, not one from photo. So mask sky with alpha then create material in ue4 that makes masked area invisible.

5. watch tutorial about cubemap sky. You need to create all that yourself.

6. That material is for most outer sky part, ie. sphere with cubemap. Again flip faces on sphere so they face inside of ball.

7. Again “skybox” is term for everything you use for fake sky. And it is not a box anymore, but it was in 1999.

Hi;
I shall watch the video tutorial and try your mentioned procedures…
Many many thanks for your time & clarifying…
Best Regards