Discovering Bump Mapping
You can left-click the Bump map next and select the same texture, or
right click to load it again from file, or even load another.
After
loading the image file (or a texture from the presets) into the texture
map, that texture map is the active map. The view that shows the map
now shows "Bump Map" instead of "Base Colour"
The bump map shows its effect as you adjust the slider next to its
thumbnail. With bump mapping, you get to see that these bumps from the
cell patterns are more pronounced, less flat.
Here's a timelapse animation
showing the changing amount of bump mapping while scrubbing the slider.
This is done in real-time!
Beyond the Bump map: the Curvy Map
Bump maps can be a very
powerful tool to make it look more detailed, give it more depth, even
though there is no actual 3D deformation involved. It is all just in
the appearance during the lighting phase of rendering. The color or
brightness of a pixel is affected by the bump map, but ultimately, not
its location on screen. The geometry doesn't change, there aren't any
more geometric details on there, even though it may look like there
are. You can tell for example that even though you may apply a very
rugged texture as a bump map, the profile of the sphere still looks
like a perfectly smooth surface of a sphere.
In order to go beyond the bump mapping effect, in order to see the
geometry actually change its shape as a result of the texture used to
control it, you'll need another map: a displacement map. Curvy 3D
supports an implementation of real-time displacement maps, called Curvy
maps. We will definitely want to explore this feature, as it is
amazingly capable and possible to create insane models within seconds
by combining geometric modeling with image based techniques.
Here are just a few teasers:
a single object made of two brush strokes (Lathe object)
The same object with a plaid pattern applied to the base color map
The same plaid pattern used as the displacement map (Curvy map). Note
how it actually displaces portions of the geometry, even though we
still have the original curves-based model, not converted to mesh yet.
Curvy 3D does this in real-time as you adjust the intensity slider.
And with yet another texture applied as Curvy map.
and even more.
Another map applied to another object: here we used the sphere from the
tutorial above and applied a bumpy pattern from PD Pro. The
displacement generates hills and valleys. The plain black bottom is
useful in the base color map.
Here's a look at dynamically adjusting the intensity slider value of
the Curvy map.
When the slider is in the middle (resting) position, no displacement
occurs. When moving the slider to the right, then the brighter, lighter
portions of the texture cause the geometry to be pushed out, while the
darker parts get sucked towards the inside. The opposite happens when
moving the slider to the left of the middle: the lighter parts move
deep into the object while the darker regions come out.
In the above example, the original sphere is still represented by its
construction curve (shown in orange), but the same real-time
displacement with Curvy maps is also possible with models that have
been converted to meshes. Internally, Curvy just manages that for you
and keeps a meshed representation for you to see that is updated
dynamically if you edit the contruction curve. The Curvy map
displacement is applied after taking in consideration the curve's
shape, if it changes. In other words: you don't have to think, it just
works :-)