At the end of the twists and turns, I finally installed an impostor baker.
I think it is great~!!
The tree looks good.
but, leaf color is too bright or too dark. T.T
If the color of the leaves is different and I change the material to match the bright side,
the opposite side becomes too dark. If change it to the dark side, the bright side becomes too bright.
IN This Screen shot
Of the three trees, the middle tree comes out well, and both trees come out strangely.
The issue was rooted in our Materials indeed - we had used a too complicated shader at first, using “Make” and “Break” attributes nodes instead of just checking the little box in the material’s property on the left that will collapse the “Attributes” node to a single, small node (where you can link the material results into).
However, we are now stuck with one more, big issue:
Our Billboards (using those instead of Impostors right now) are being created with textures that -do- have Alpha Channels in UE4.
However, when we export them, all we get are .HDR images.
Once we import those into an image editor, the alpha channel is lost, thus making it impossible for us to work with them :(.
Ryan pointed me towards the right direction - if any of you encounter similar problems, you can find a “sort-of”-solution here in the comments section (10/28/2018):
If you need more explanations, feel free to shoot me a PM!
Also interesting to know - you can change the brightness / darkness of the Impostor Materials in the MI settings. Also try adjusting roughness and specularity to fit your model!
What else we did was to let Impostor Baker render out “Opacity” instead of “Depth” map for a very hard / clear additional opacity map that we combined with the soft one in the basecolor alpha channel. Eventually, our billboards looked much more solid and true to the original’s color.