are numerous plugins available for Max, which will produce such an image. This
is normally done by the plugin changing the renderer and materials, but some will
not let you to mix styles, or achieve a specific style that you are after. Another
method is to apply an overall effect in Post; a Photoshop filter will normally
do a quick but effective job, but, again, if you want to mix styles, then this
is not the way to go.
can, with some minor amendments here and there, create standard Max materials
to produce an NPR effect. The most commonly used one would have to be a cellshade,
but as this was covered in a Q&A back in issue 4, I’m not going to go into detail
for this method, although I advise you look into a Gradient Ramp map, with Lighting
type and Solid interpolation, mixed with a Falloff map set to Fresnel. Other effects
can be generated similarly.
general rule when designing materials for NPR is that nine out of ten times, there
has to be actual shading on the rendered objects. The shading and shadow effect
is generated by lighting; with shadows cast and various degrees of luminance (etc)
from assigned materials. This is normally in the form of a graded shade or (almost)
solid block colour for a shadow. Basically, what we need to do is to remove all
block and graded shading from an object, then design the shading method ourselves.
And the best way to do this is to crank the self-illumination up to 100%.
shall look at producing a pencil sketch, mainly because in this style, shadows
are not a solid colour, but vary in intensity due to the pressure of the ‘pencil’.
So how do we produce this pencil effect? Easy… with a pencil. Three or four different
intensities of shade should be produced, from very light to almost charcoal. These
should then be scanned and tiled in, say, Photoshop. Next, we have to add these
maps to the material in such a way that they will change from one to the next
depending on the amount of light received. This is achieved by using multiple
Falloff maps in the diffuse slot, with each pencil texture applied in the dark
slot (from darkest to lightest), and the next Falloff map in the light slot. And
so on until all textures are used.
that each pencil texture set to screen environment mapping, so it appears that
the image has been applied directly to the ‘paper’ and not wrapped around objects.
The beauty of this method allows you to even use raytracing in your materials,
and by copying the falloff map tree into the Basic Tinting slot of the Raytrace
map, you can even make reflections appear in the same style, or not, depending
on your preference!
could also make the hand drawn effect more effective by using animated pencil
textures, about 10 frames should do for each pencil shade, to give the impression
that the entire animated sequence does not move behind the sketch effect.
published: 3D World magazine,
Issue 15, August 2001.
2001. Reproduction without