V-Ray for SketchUp - Bump and Displacement - tutorial Video Lecture | V-RAY Tutorial (English): For Beginners to Beyond - Professional Skills

this video tutorial is using bump
mapping and displacement mapping in
v-ray the goal of this tutorial is to
show you the difference between bump
mapping and displacement mapping so that
you can add more detail to key parts of
your scenes and achieve more realistic
renderings bump mapping is a shading
effect that is used to simulate the
subtle bumps on the surfaces of geometry
the bump map effect does not deform the
geometry here we have a simple plane the
goal is to add detail to the geometry
with the bump map effect this will
eliminate the need to model the details
in order to add the bump mapping click
on the material and select the material
in which you want to add the mapping to
enable the bump map effect and then
click on the M button to add the map
select the text bitmap for the type of
texture map next click on the file
browser button to select the image you
want to use for the bump effect
image is used for bump and displacement
maps should be grayscale images in v-ray
the black areas mean zero in terms of
the depth and white means the maximum
depth that v-ray can reach using bump
mapping
the multiplier controls the depth of a
mapping notice in the rendering that the
bump mapping adds some detail to the
image to increase the depth of the bump
mapping effect increase the multiplier
to 20
let's render this scene
bump mapping is only a shading effect in
some cases you may not be able to
achieve the depth required for the
amount of realism you are trying to
achieve to achieve more depth you must
use displacement mapping now that we
have looked at bump mapping let's take a
look at using displacement mapping
displacement mapping is a method for
adding details to the geometry and is
similar to bump mapping the difference
between displacement and bump mapping is
that displacement actually deforms the
geometry and allows you to obtain more
depth
in order to add the displacement mapping
select the material and enable the
displacement option
and then click on the M button to add
the map select text bitmap for the type
of texture map next click on the file
browser button to select the image you
want to use for the displacement effect
here is a rendering showing displaced
geometry
notice how the geometry is now deformed
and there is more depth and detail in
the rendering the unit system in your
scene does not relate to the units for
displacement the unit system for
displacement is always in inches for
example if your scene units are in
millimeters a multiplier value of 1 will
increase the depth of displacement by
one inch and not one millimeter there
are two ways to control the options of
displacement mapping v-ray has global
displacement settings available in the
v-ray options dialog these settings
control all displacement mappings in
your scene there are also settings
within the v-ray material to control the
displacement per material in this scene
we will control the displacement per
material to enable per material
displacement disable the global option
once this is disabled you will control
displacement settings in the individual
materials the most important option in
the displacement settings is the edge
length option this option controls the
quality of displacement the smaller the
edge length value the higher the quality
the higher the edge length value the
lower the quality
the value of the edge length tells
bewray how long in pixels the edges will
be for the final deformed geometry
let's set the edge length value to 2
you can immediately see the higher
quality of displacement in the rendering
look at this example of bump and
displacement mapping with a brick
material
let's add a bump map using the same
technique as in the first example
you
notice how the surface has more details
but it doesn't have geometry deformation
let's render this scene
look at the result using displacement
mapping and the same texture map used
for bump
by adding displacement notice the
deformation of the geometry the results
are more realistic without having to
model the details
here is another example in a common
architectural scene displacement is used
on the stone wooden siding and grass
materials in this scene
the edge length used in the scene is 12
this will give you lower quality but
will result in faster rendering time if
the edge length is set to 4 you achieve
a higher quality but the rendering time
will increase in this scene edge length
values range between 8 and 12 to provide
results with a good compromise between
quality and speed
max subdivision is another important
option this option controls the maximum
sub triangle division of the surface the
default max subdivision value of 256 is
the recommended value for most cases if
you require more subdivisions we
recommend that you subdivide the
original surface or mesh instead of
increasing the max subdivisions this
wall is an example of a surface that has
been subdivided notice how the surface
is divided into smaller areas let's
render this scene
you
the rendering time and quality of this
image is more than acceptable
during this rendering process you can
see that the rendering buckets calculate
quickly and with high quality the edge
length is set to 12
the final image has excellent edge
deformation to define the wooden
boards
and excellent detail in the surface of
the wooden boards
in the image on the right we are not
using displacement you will notice a
straight line at the edges and corners
of the wooden boards
this shows that there is no deformation
in the geometry
the detail added by using displacement
is also visible in the areas where we
have grass in our image
bump mapping is an effective way to
simulate some surface depths in your
scene however displacement can allow you
to add more detail when you are trying
to achieve more realistic renderings