Texturing with HDR images possible?

I would like to texture map my environment with HDRI OpenEXR images based on photography of a real location. These images are in linear color space and contain far more brightness information than a non-floating point format like targa can store.

Can anyone shed any light on whether texture mapping models with high dynamic range imagery (in any floating point file format) is possible in UE4?

Many thanks.

If you then look at M_Procedural_Sky_MASTER_UE4 you can see how the material is setup.
This relies on an .HDR file with a 16 bit float formatted texture. to work, it can be of non power of 2 formatted, as it’s not required for this application. (es Unreal Imports .HDR files)
Then use the SM_SkySphere in your scene, and override the default material with your new sky material.

My Question to Epic, is why it’s so blurry, I’ve taken a 7K texture and loaded it in, and found no detail like what I saw in Photoshop, but if I take it, convert it to a 2048 x 2048, or 4096 x 4096 and load it onto a sphere it’s crisp as heck. I’ve played with the LOD bias, as well as turning Mipmapping off, and no difference.

Thanks for the response DCrosby. Very clearly described and I will check that out.

Pardon my ignorance, but the method you describe seems to be geared towards sky boxes which some game engines treat as special cases for HDR textures. Can the same HDR material you describe creating be then applied to all your UVed scene geometry - wall, floors, tables etc?

Unfortunately, due to being in heavy production on a TVC in Maya right now, I am restricted to asking theoretical questions here rather than rolling up my sleeves and experimenting myself. So sorry if I come across as lazy.

Cheers.

Not at all ! So no HDR’s are for skyboxes exclusively. I’ve thought about how cool it would be, to slap a texture of a HDR Image of a Matte Box, on a poly cube, and using it for lighting. At this time it’s not at that level. Also, they have IES profiles for lights to replicate the beam pattern of certain lights, and you can download IES profiles from bulb manufacturers (Sylvania, Bosh, GE, Etc…) supposedly, although I’ve only found them on CG Websites…

When you try and hook an HDRI into a Texture Sampler in a material it expects a CameraWS vector, and typically an offset, of -1,-1,-1 to flip it around. into the UV input, if you don’t it won’t go into the emissive channel, and error out. Also you typically have to set the material to Unlit. All of which make it useless for Material Surfaces.

One of the “Walls” I’ve hit is taking a clean HDRI with plenty of resolution, having it not Blur when projected onto the sky. My Solution is I then down-sample the HDRI to 8bit / Chan (24Bit), and project onto a Sphere, which works but creates other issues with Directional Lights, and Parallax. But is much clearer. The other part is to use a Sphere with a flat bottom to project the floor onto, to use as a HDR environment to place objects into to display to have accurate IBL Materials, and then shift the HDR to another, and check it against varying lighting conditions, and still have shadows cast onto the floor. The floor thing Eludes me, since the resolution is so opposite to what you’d need. With the highest pixel density close to you. As well as we have no shadow receiving objects, which only capture the shadows, and project them onto a piece of geo below, or the BG.

Also even though this is for you, this was the first topic I found on HDR integration into unreal, and therefore I’d like to set this up as a knowledge foundation to build upon, and have others discover. This is what I’ve unearthed messing with it, since the Beta.

Use EXR format than HDR. Then use 2d texture sampler, not cube map.

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I’ve been wondering the same thing. It seems like texturing with HDRIs of some kind would give LOTS more options and freedom with color grading effects and whatnot. Skydomes, sure that’s pretty much a given, these days, but the next step is floating point textures.

That being said, I’d be really surprised if procedural materials don’t have that kind of precision… but it doesn’t help with your case.

I’d like to know the answer to this question, too.

im almost sure that 4k texture is top that you can use from acratch, try to search something like “Activate 8k texture support”