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New player : light set up to produce normal map and normal map question

Hello everyone,

My name is Rapha

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  • chronic
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    chronic polycounter lvl 10
    normal maps do not store lighting information - they store surface normal information. many people mistake the coloring in a normal map for 'shading' but its not; converting it to greyscale is an arbitrary operation.

    you are going to have to try something else to get 'baked lighting' in textures.

    1. by far the best and easiest (imo) is to hand paint the textures, you can take advantage of overlaping and create any creative effect you want

    2. you can apply your normal maps to your object through a shader, set up an interesting light rig, and try and bake the lighting to a texture using mental rays batch bake (or something similar). This is by far a more complicated and technical process. This video, describes a similar task.

    3. you can bake ambient occlusion maps instead - this may give you at least some sense of 'shading' or be a starting point for hand painted textures. but it probably wont be very noticable on such a simple object.
  • cornu
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    Chronic, thanks for the answer !

    I know understand that the shadow and light "incoherences" on my grey-ed out normal map are just the result of turning the red green and blue channel into arbitrary grey.

    My initial plan was to hand paint the texture, but as you can see on the last screenshot, I wanted to paint lines and details, and I did not find any technique to draw straight lines over various unconnected polygons. Maybe it is the way I did the seams in Maya ? I wanted to avoid deformation.
    I want to have a "guide" of the geometry I need to paint and put on a layer in photoshop so I can fake shadows and such
  • chronic
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    chronic polycounter lvl 10
    ignore my sugestion #2
    a better solution would be to use the transfer maps tool - it lets you do normal maps and AO between high and low res - but Also lets you bake full lighting and shading info between high and low res objects to a texture
  • Eric Chadwick
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    How about UVing each of the three "bands" in a straight line, not as four curvy disconnected "leafs"?

    And like chronic suggests, bake an ambient occlusion map for a painting guide.

    In Photoshop if you want clean curved lines, you could use Paths instead of just hand-painting it, since they offer bezier handles for fine-tuning. You could also use the Paths as selection masks for painting.
  • kodde
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    kodde polycounter lvl 19
    There's also the Cavity map features in XNormal as an alternative to using Ambient Occlusion when considering adding a pass to your textures. There's even a Normalmap2Cavity Photoshop plugin.
  • cornu
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    Hi,

    Thanks for your suggestions ! I guess I was making too big of a deal of possible texture deformations. I followed EricChadwick suggestion and UVed the band in straight line and used the blue channel of the normal map as a guide for texturing.

    debuttexture.jpg

    I realise I actually miss the knowledge and experience of photoshop, wich I can only get by practicing ... :)

    Can any of you tell me why I get UV shells that are of totally different scales ? Some of them are like 10 times biger than they should be, some I can't even see on the screen. Is it normal behavior or should I get same scale UV shells ?
    (Maya, how I unwrap UVs : select object, automatic UV, edge mode, change seams, clic on the icon that unwrap object again (can't remember name))

    Cheers,
    Raph
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