Lunaran's Quick Normal Map Trick
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Lunaran's Quick Normal Map Trick
- See original at: http://www.doom3world.org/phpbb2/viewtopic.php?f=2&t=9056
No, no no, forget all that. Do as I do: Take the wall model in your 3D app. Point an orthographic camera dead at it, and try to frame it nice. Drop in an ambient light with intensity 0.5. Drop in these directional lights, all at 90° angles to the model: RGB 0.5, 0, 0 from camera right RGB -0.5, 0, 0 from camera left RGB 0, 0.5, 0 from camera down RGB 0, -0.5, 0 from camera up RGB 0, 0, 0.5 from the same direction as the camera (facing). Render at resolution of choice, preferably with AA. Garnish with oregano and a dash of paprika. Crop/downscale in PS. Voila, perfect normal map, identical to what Orb or Doom3 will give you, in much less time. Next week: chicken marsala!
A similar method using real-world photography: