such a scene can be both easy and difficult to produce. Easy with
some terrains such as fields, vast open planes (etc) and more difficult
with others such as areas with dense populations, woods, trees,
rock formations and so on. All these need to be modelled, and if
you’re going to be viewing the entire scene right to the horizon,
then you’re going to have problems (especially if that unforgiving
deadline is approaching!).
To make your terrain look more realistic, it’s best to base
it on an actual scene or photograph; these are some of the best
references you can get apart from actually being there! Also, to
get the exact detail of the surroundings, look into topographical
maps of the area; something as detailed as a 1:25,000 or 1:50,000
map will suffice for this. Using these maps, an accurate representation
of the terrain can be created by painstakingly recreating the map
in your 2D paint package; drawing out field boundaries, contours
for displacement of your mesh, roads and areas of population. This
might sound like madness, but if it’s a faithful representation
then detail is the key to realism (but don’t go too mad!).
these generated maps (displacement, diffuse, bump, specular and
any mix maps for rivers, streams, decals etc) we can take them into
Max and assign them to a large Plane primitive that stretches off
into the distance. With high iterations (or set to generate detail
at render time), the plane will use the displacement map generated
from the source map to create the hills and valleys of your landscape.
Simple. Using the maps created for the diffuse (etc), assign them
to the terrain, and you’re just about there! The terrain may
require some extra displacement and refining to create finer detail
such as rougher terrain, steep banks, hedgerows and so on. With
so much detail in the viewport, it might be advisable to either
Optimise or apply a MultiRes modifier (which may take an age to
calculate due to mesh density) and collapse the mesh..
the terrain has been refined, we can add more detail such as trees,
woods and populated areas by carefully postioning these items over
the terrain which will take an age, or by using Scatter compound
objects working on selected faces to distribute specific items on
specific areas of the terrain’s surface.
Rendering off the scene, we can see the terrain stretch off into
the distance, yet a sense of scale is still not apparent. By using
a camera with a wide field of vision, such as a stock 28mm lens,
we can get a better sense of proportion. Still it doesn’t
seem quite right yet. Creating a simple skydome helps, but by observing
real world environments, we can see that colours desaturate as they
fade off into the distance. Environment fog helps here, and it is
advisable to slightly tint the fog a similar colour to the horizon
colour of your sky’s texture to nicely blur the horizon.
finish off the image, we can add some clouds to the scene. A simple
bitmap texture would normally suffice if we are viewing the scene
from ground level, but as we are positioned at cloud level, we will
have to create the clouds themselves. The clouds are created by
using a Particle Array particle system that is distributed across
a large Plane primitive that has been displaced using a Smoke map
to create the irregular formation of the clouds. The particle system
itself is assigned a simple material, virtually transparent as not
to totally occlude the terrain when rendered. Add careful lighting
(excluding certain geometry from specific lights, raytraced light
to cast shadows on the ground from the main light source etc) and
the scene is complete!
With such a high particle count, and the density of the terrain,
our scene’s face count may fall into the millions, but careful
optimisation of geometry and snapshotting of particle systems will
reduce render times at the expense of larger max file sizes, which
is pretty negligible.
materials for the scene can all be generated from a single map
obtained from a website or purchased over the counter. Creating
these maps can be a time-consuming process, but the end result
is worth more than simply applying procedural methods to the
surface as the end result looks more realistic as it is based
on a real-world terrain.
base scene consists of a simple high polygon plane primitive.
Add a Displace modifier to the plane’s stack and assign
the displacement map to it. By amending the Strength spinner
we can see the terrain deform to fit the displacement map. If
you find updates in the Viewport are slow, then amend the Plane
primitves iterations to a lower amount and increase the Density
multiplier to a higher factor.
the mesh by smoothing out any irregularities caused by the displacement,
and add or collapse polygons to increase detail in specific
areas to bring out more detail in the displacement procedure.
Additional displacement maps can be used here in conjunction
with Subdivision displacement that occurs at render time.
||Add a simple
hemisphere to the scene and assign a sky material to it. To
add more realism to the render, add a camera with a wide field
of vision such as the stock 28mm lens. Increase the Far Range
spinner so that the environment range planes of the camera are
placed well into the distance. Add Environment fog to the scene
and check on Exponential. You may wish to tint the fog to the
colour of the sky’s material to blend the sky and land
the clouds, create another plane primitive with a high number
of polygons that encompasses the scene. Add a displacement modifier
to the plane and add a smoke map to the displacement modifier.
By amending the strength spinner in conjunction with the size
of the smoke map, you should see the plane deform to create
an irregular-shaped surface. Create a Particle Array particle
system and select the cloud plane as the distribution object.
Hide the distribution plane to ensure it isn’t rendered
(or un-check “renderable” in the object’s
the number of particles so that the entire surface is covered,
take the speed down to 0 and set the particle start time to,
say, -50 to ensure the particles are already born at frame 0.
Change the particle type to sphere, or use instanced geometry
is desired. Increase the particle size so they are quite prominent
and add a high size variation. Assign a near-transparent material
to the scene with a falloff map in the opacity slot to remove
any visible edges of the particles at render time.
and the final image. The terrain map can still be seen while
the clouds are prominent and occlude any horizon line or the
edge of the terrain mesh.
you wish to texture your clouds so that some areas are more dense
than others (ie darker), create a Mesher compound object and assign
the particle system to it. You can then assign additional modifiers
to the “particle system” and easily add UVW modifiers
to it and then shade the clouds to your heart’s content!
To create holes in the cloud formation,
apply a Volume select modifier to the particle system’s distribution
plane object. Reposition the Gizmo so that only the peaks of the
plane are selected and ensure Face sub-object selection is checked
on. Back in the particle system check on Use Selected Sub-Objects
and the particles will only emit from the selected faces. Alternatively,
delete the unwanted faces from the distribution plane and check
off Use Selected Sub-Objects in the particle system should you find
updates are too slow.
Add detail to the terrain by using
Subdivision Displacement. By using additional displacement maps
in the object’s displacement section of the material assigned
to the terrain, you can create simple yet effective detail at render
time as not to impede your workflow when working in the viewport.
Although all well and good for most
applications, Max’s particle system isn’t the best on
the planet. Although it’s more challenging to try and achieve
something that you would normally only get with a plugin, for complex
cloud formations and volumetric smoke you may well be better off
looking into plugins such as Afterburn or Pyrocluster for the volumetric
World magazine, Issue 26, June 2002.
Draper, June 2002. Reproduction without permission prohibited.