Splatmaps for Landscapes are mid-gray instead of 0 - 1. about houdiniengineforunreal-v2

[bitsalive-ron]

PS: Tried to export the maps via the Labs tool and those are going full 0-1 white. So i guess this is the required workflow.

[dpernuit]

Hi Ron,

Sorry for the late reply, it took me a while to get to the bottom of that issue ;)

So here's how the landscape layers are converted by the plugin:

• by default, we use the layer's min/max value to convert it from float (H) to uint8 (UE). Basically [min max] ends up as [0 255] in the landscape layer.
• we also allow conversion using [0 1] instead of [min max].
  Any HF value that is out of the range is clamped to [0 1] before converting the values.
  Basically this ends up converting [0 1] to [0 255].
  That mode can be enabled by adding the "unreal_unit_landscape_layer" primitive attribute, with the value set to 1 on the layer that you want to convert this way.

Note that if the HF mask that you are converting has values out of [0 1], the default conversion will look grey compared to the one clamped to [0 1].

For the labs tool, I guess you used "terrain layer Export", it basically works by default by limiting the values to [0 1] before exporting the file.
If you first remap your mask (via a HF_Remap) so its value are converted to [0 1], then you' ll see that the labs tool will produce grey images as well.

Here's a few pictures to illustrate my point, all from the same HF (the Houdini Engine pictures are flipped due to axis conversion).
The Original range of values on the source water volume is [-2.38419e-07 3.82061].

Here's the water layer, converted straight from my HDA. (min-max to 0-255)

and here's the same when using the "unreal_unit_landscape_layer" attribute (0-1 to 0-255):

Here's the default output of the labs tool, that actually thresholds the values in [0 1]:

and the labs tool output after I remapped the water mask to [0 1] before the export.

TLDR: if you'd rather use the whiter/thresholded images, then use the "unreal_unit_landscape_layer" attribute. But thresholding the values actually destroys some of the details on the image, as anything out of range will be clamped.