Normal map from a texture
polycounter lvl 11
Hi people,
Got a question that I did not find a satisfying answer to searching the PC forum. I have a high poly and a low poly asset put together and got the normal maps projected onto the low poly. It is a concrete road block and I want to capture more detail out of the concrete texture.
When I used Max I used to add a bump map of the texture and also use the normal for the high poly detail. In the case of maya I added my normal map under the bump map slot of the shader, but where would you add the bump map for the texture? Or would you create a second normal map of the textures and combined it with the high poly one and add them as single map.
I hope I make sense of what I am trying to ask you guys. Let me know if it is not clear.
Got a question that I did not find a satisfying answer to searching the PC forum. I have a high poly and a low poly asset put together and got the normal maps projected onto the low poly. It is a concrete road block and I want to capture more detail out of the concrete texture.
When I used Max I used to add a bump map of the texture and also use the normal for the high poly detail. In the case of maya I added my normal map under the bump map slot of the shader, but where would you add the bump map for the texture? Or would you create a second normal map of the textures and combined it with the high poly one and add them as single map.
I hope I make sense of what I am trying to ask you guys. Let me know if it is not clear.
Replies
Than just save that out and use the new normal map on your LP.
for game assets your much better off putting all the bump and normal detail in one normal map.
also if you got a working bump map you can just run that threw NDO or the nvidia normal map filter to make a normal map version to overlay on the bake.
nDo will do it or do it by hand. Adjust the levels of the one you're laying on top to output only 1/2 of the blue channel (so instead of 0 to 255 take it down to 0 to 127/128) and set the blend mode to overlay.
why do you do this? The leveling that is.
0-0.5 (or 0-127) in the blue channel means the forwards vector gets reduced so much that it points backwards. Hence the strong blue tint to tangent space normal maps, it's range in most circumstances stays within the 0.5-1 range because any less than that and it'll appear to get lit from behind.
You can pull some interesting hack-y tricks with the underside of foliage and an inverted blue channel to get a "backlit" effect, though
Thanks again for all the tips!
http://www.polycount.com/forum/showthread.php?t=48999
but also any overlaid normals i do are generally just surface detail, expect for the odd case where i did everything by hand in photoshop, i have all larger details where depth would be important in the bake.
http://www.poopinmymouth.com/tutorial/normal_workflow_3.htm
You would still get better results in CrazyBump than adjusting levels in Photoshop w/ Overlay, however, at that point, they're only minimal.
However, never, never, never just overlay a normal in Photoshop. When you do, 3d math geeks the world over cry.
ya always adjust or level the blue channel in PS but any advantages you get mixing hte maps in crazy bump or so minimal that it prolly isn't worth have to kick things out to a different app and pasting the results back in PS.
which is why i tend to use NDO over crazybump, allows me to work easily with normal maps in the PSD, and keep there settings intact, if i want to tweak the normal map later.