When modeling
a landscape, the best method to use involves a Displacement map,
that deforms a Plane in such a way, that higher and lower areas
(mountains and valleys) are created. Let's start with creating
a Displacement map in Photoshop:
I have created the basic structure
of my landscape on a 500x500 pixels image. Low land is in black, whereas
the white areas define where mountains should arise. You should only
draw the general height difference, we will fine-tune it later in MAX.
Image 1 shows the rough outline of the landscape: a (black) valley in
the middle, that rises up to the sides (white).
1. The basic model: Create a Plane (R3 only, 2.5 users
will need to use a Box) in the top viewport. Set its extents
to 1000x1000 units and give it 30x30 Length/Width Segs. If You
need to use a Box, use the same parameters, but it must not have
any height. Apply a Displacement modifier to the created plane.
Then click on "Map" (not "Bitmap") in the
"Parameters" rollout, and choose "Bitmap"
from the window that appears. From its parameters, choose the
rough displacement map You made in Photoshop. To give the whole
its actual height, change the "Strength" value to 200.
You now have a rough landscape effect. To keep the landscape
level, You should check the "Luminance Center" option.
Open the
Material Editor and put the Displacement map from the plane's
modifier stack into the diffuse channel of a material, choosing
"Instance" when prompted for a duplication method.
Apply this material to Your landscape. Now we will add details
to our Landscape, to make it look more interesting. To do this,
we will first increase the number of segments in our plane. This
is simple enough for R3 users: simply go back in the modifier
stack to the plane, and increase the "Render Segs"
parameter to a value of 12. This subdivides the plane at render
time, whereas the viewport model remains at a low-polygon level.
2.5 users need to use a different method: Apply a Meshsmooth
modifier, and set change its operation to render-time only by
changing the light bulb (at the top of the rollout) accordingly.
Then increase the "Iterations" parameter to 2 or 3
(the higher this value, the more detail the Landscape can display).
This gives You (almost) the same result as with R3, but with
somewhat more work.
2. Details using a Noise map:
Make a test render. Your landscape should look somewhat like the one
n Image 2. Now to add more detail: Go back to the Material Editor and
to the diffuse map. Click the "Bitmap" button next to "Type:",
and elect "Mix" from the list of map types. In the window
that pops up, select "Keep old map as sub-map". You have now
made the rough landscape map part of a mix map (this also applies to
the displacement map in the modifier stack, as we made an instance!).
You've now got thousands of possibilities to further change the landscape
(oh God, how to explain this one??): Your landscape map is in the "Color
1" channel. Change the mix value to 40, and click on the available
"Color 2" map channel. Choose the "Noise" map type
from the list. You're now at the Noise map level. Change the type of
noise to "Turbulence" in the Noise Parameters rollout. Give
the noise a size of 60, set the "High" noise threshold to
0.4 and the "Low" noise threshold to 0.1. Change the number
of levels to 5. Now to change the colors: Set color 1 to a light gray,
and color 2 to white. Those are the settings I used.
If
You haven't had much experience with the "Noise" map, play
around a little with the different values. Change the values only a
little at a time and make test renders to see how the landscape changes.
For example, take the size of the noise map and double it. Instantly
the Landscape has gotten a different look to it. Play around with the
high/low threshold values: These have a large effect on the result,
especially with the turbulence noise type. You can change the look of
the landscape completely with these. Lastly, the mix value, that determines
how much the noise map is mixed in with the original "Photoshop-Landscape"
map, also has a high impact on the end -result.
Whether You use my example values, or make Your own landscape... What's
important is: The basic structure of the landscape that You made using
Photoshop, is preserved. Mountains and valleys are apparent in the model.
The dimensions (huge Alps, or calm hills) are controlled by the noise
map. My landscape now looks like that in Image 3 (the Mix map made everything
a little flatter, but that's ok - You can always increase the strength
of the Displacement map again).
Back to Photoshop:
Now
on to texturing. To make Your landscape look good, You should
be able to tell the difference between flat areas (grasslands,
snow-covered areas) and step cliffs. We need a map that clearly
shows this. I call this an Inclination map (white=steep cliffs;
black=flat areas). To create such a map, render a top view first.
The bigger the render, the better; the detail of Your landscape
depends on this. I rendered an image at 2000x2000. Make sure
You applied the Displacement map as a Diffuse map to the landscape
as well. Change the self-illumination of the material to 100
(un-check the "Color" option!), so that the landscape
is not affected by the default lighting in the scene¹. Save
the rendered image as "Inclinationmap.tga" (See image
4).
Open the Inclination map in Photoshop, and
clip it to its boundaries (with that I mean, get rid of any black edges
around it), in order to be able to map it back onto Your landscape perfectly
later on. In case your map has fairly little contours (like mine), You
could increase the contrast by using the Tone values (non-Photoshop-experts
can simply use Image > Settings(?) > Auto contrast).
Then choose Filter > Stylize(?) > glowing outlines. Play
around with the values a little, so that You get a result like
that in Image 5. This filter allows us to visualize any contrasting
areas: A strong contrasting area in the Inclination map (a steep
cliff in the displacement map) will become white. Low contrasting
areas, i.e. areas with little change in colors (= little change
in height in the Displacement map) will become black.
Optionally,
You could apply another tone correction to the new image, to
increase the contrast a little further. Save this map as "Inclinationmap2.gif"
(to save space).
The
landscape's texture:
Now back to MAX. We need two textures: one for the flat areas
(say, snow), and one for the cliffs (where the snow won't stay).
I won't describe here how I made the two textures. Simply check
those out from the example MAX file. Let's assume You made two
different types of textures (snow and rock). Now all You need
to do is mixing these two together using the inclination map,
and applying it to our landscape. To do this, make a new material
in the Material Editor, and choose "Blend", not "Standard"
as the material type. Blend is similar to the Mix map, but here
You can mix complete materials, not just two textures.
Put the snow material in the first channel, and the rock material
in the second. As a Mask, choose "Bitmap", and pick
the Inclinationmap2.gif as the file to use (should the snow and
rock be the wrong way around, check the "Invert" option
in the mask bitmap's "Output" area).
I have then added
a sky and some fog to the scene. Done. The whole effect is made or broken
by the texture.I The inclination map should make sense on the model
(it's a little off in the example scene) If You think it's not quite
right, it's back to Photoshop and trying the procedure again with different
values (isn't that much work). The texture of the rock is also of high
importance. Check out the tutorial
for making rock materials for more information.
Addition
(May
24th 2000)
There's
also a freeware plugin that completely eliminates the need for
an Inclination map. The Terrain
Material from Johnny Ow (www.bigpixel.com) makes the whole
thing a lot easier. Put the plugin in Your MAX Plugin directory,
and it will show up in the Material Editor next time You start
MAX.
Have fun!
¹ Note from translator : You will also
need to set the Shininess/Shininess Strength parameters to 0.