Hey folks,
I’m currently playing around with textures in the Cycles render engine using nodes and I’m hitting issues, especially with specularity. I’ve attached a screenshot of my node tree, the rendered image, and the reference output from CrazyBump (where I generated the spec, occ, disp etc.). Any ideas on where I might be going wrong?
CrazyBump
Cycles Node Tree
Cycles Render
Thanks,
Tristan.
No lights/bad lighting, object scale something else than xyz(1,1,1), no UV map, image texture node set to color for normal, and only presenting the symtoms.
In my example there are lights and even with good lighting it still looks wrong, it has been UV unwrapped and mapped and the image texture node for the normal is set to non-color data. The biggest issue I’m having is the specularity making the texture B&W on the highlighted areas and just simply not working as you’d expect. I’ve probably done something wrong with the node setup but can’t quite work it out yet.
It would help if you didn’t have some of your nodes collapsed so we can’t see the settings on them.
Uncollapse your spec group. Your spec map is mixed to almost pure black, so you shouldn’t expect to see much. You should use a colorramp to adjust levels. Spec map image should be set to non-color data.
Please note that normal maps generated outside a 3D program have to decide between 2 different formats of up direction. No idea which one crazybump chooses. A good generator will offer you a choice…
For a cobblestone or tile texture (like yours), in which the lines are low and the polygonal shapes are high, Blender prefers –
Good:
Bad:
Just my own personal observation.
Spec map needs to be plugged into the color input on the glossy node. Mix factor should either have a fresnel node attached to it, or be left unconnected.
Based on all the advice/suggestions of all those who replied, this is what I currently have, definitely looking much better (still need to mess around with the nodes a little).
Nodes
Render
Please note that normal maps generated outside a 3D program have to decide between 2 different formats of up direction. No idea which one crazybump chooses. A good generator will offer you a choice…
I think this may be an issue as you can see from the render the stones appear to be sunk in while the surrounding areas are raised. I’ll have a play around with the options tomorrow, but I remember CrazyBump having options for the Normal map y and x axis’s; those being Up, Down, Left, Right.
