Sparkling Grape Juice Glass – Modeling and Rendering

LEARNING TARGETS:
»  I understand how to: (in Maya)           - create and edit curves including attach and detach.
          - revolve a NURBS surface.
          - import an image plane and edit its attributes.
          - apply new materials and change basic attributes, color, transparency

EXPECTATIONS:

»  CREATE:

VIDEO NOTES . .

Import the sparkling apple juice glass as an image plane in the front view window.
In the front view panel menu, choose View > Image Plane > Import Image . . . then browse to find the image plane that you want to use.
*The image in posted in Blogger needs to be renamed because Maya does not like files with brackets “ [“ in the file name.  Blogger changes file names when you upload them.



 
ChannelBoxMove the image so that the glass sits on the baseline.  I set Center Z to –20 so that it sits behind the grid and then Center Y to 2.26. 
If you loose the your image plane settings you can get them back in two ways.  Select it until the image plane’s border turns green and the open the Channel Box.
It should look like this . . .
WineGlass_image_Plane

Using curves draw a half slice of the wine glass.  I made 3 different curves.  The first thing you should do is switch your front view.
inner_curve0
Once your curves are made adjust them so that they have a smooth flow that outlines the outer edge of the glass. To do this, Right Click on the curve that need adjusting and choose Curve Point.
inner_curve0-1
It should look like this.  Now using the Move Tool, adjust the vertices accordingly. 
inner_curve0-2
Duplicate the side curve [CTRL + D] and move it slightly inside or left to define the inner edge. 
inner_curve
Right Click on the curve and choose Curve Point.
inner_curve2-5
Move the Curve Point to roughly the middle of the curve. Then choose Curves > Detach Curve.
 inner_curve2
Delete the lower curve.
 inner_curve3
Right click on the curve again, choose Control Vertices, and then adjust the curve vertices to shape the bottom of the glass.
inner_curve3-5
It should look something like this.  Now we have to attach curves.  Select all curves and choose Curves > Attach Curves.  Make sure you uncheck Keep Originals and check Insert Knots in the Attach Curve option box. Then delete the curve history.  Select curve, Edit > Delete by Type > History.
WineGlass_curves2
*Note: if your curves act funny after combining them, check to make sure the beginning of one curve connect to the end of another.
It should look like this, all one curve.
  inner_curve4
Revolve the new curve.  Change your Maya tool bar menu to Surfaces then choose Surfaces > Revolve.  Right now we are going to use default settings, but if it does act funny you will need to reset setting on that tool.  By default Maya will revolve the curve as a NURBS surface.
It should look something like this . . .
WineGlass_revolve
Switch to x-ray mode.  Shading > X-ray
It should look something like this . . . You should
XRay-Glass1
CREATE THE GLASS CONTENTS
Hide the new geometry to reveal just the curves again.  There are at least two ways to do this.  Hide the object - {Ctrl} + {h} or in the active window menu choose Show >  and then uncheck NURBS surfaces
Duplicate the glass curve and hide one of them {Ctrl} + {h}.  It is good to save the original curve for later use. 
Using the Curve Point Tool, slide the point on the curve to determine how much ‘sparkling apple juice’ is in the glass and then detach curve.  To do this, Right Click on the curve that need adjusting and choose Curve Point.  This will separate the curve into 2 parts.  Then choose Curves > Detach Curve and then delete the extra outer curve.
WineGlass_curves5WineGlass_curves6
Create another curve for the top of the fluid.  Add some additional points so that you can curve the fluid where it touches the glass to surface tension. 
Liquid
Adjust the vertices to simulate the surface tension and create a meniscus.
For liquid standing in a container, a meniscus forms.  It can be convex or concave.  A concave meniscus indicated that the molecules of the liquid have a stronger attraction to the material of the container (adhesion) than to each other (cohesion).  A convex meniscus indicates the molecules have a stronger attraction to each other than to the material of the container.
A concave meniscus
Liquid2
Select  the 2 curves that make up the ‘juice’, top and side.  and choose Curves > Attach Curves.  Make sure you uncheck Keep Originals and check Insert Knots in the Attach Curve option box. Then delete the curve history.  Select curve, Edit > Delete by Type > History.
Now revolve the ‘juice’.  Switch to x-ray mode, it should look like this. 
XRay-Glass
These are the two pieces of revolved geometry.  Assign a new material to the glass, which offers secularity attributes, Right-Click on the material and choose Assign New Material.      Select aiStandardSurface.  The glass should change color slightly.
  material 
Image Based Lighting:
Add a Skydome Light. 

Talk about indirect lighting. NOTES!

In our case, the main light source is in the ceiling. Look at the top your hand, why is the bottom of your hand not completely in the shadows?

Reflecting Light is a transverse, electromagnetic wave that can be seen by humans.

The photon is the basic "unit" of light.  Any light that you see is made up of a collection of one or more photons propagating through space as electromagnetic waves. In total darkness, our eyes are actually able to sense single photons, but generally what we see in our daily lives comes to us in the form of zillions of photons produced by light sources and reflected off objects. If you look around you right now, there is probably a light source in the room producing photons, and objects in the room that reflect those photons. Your eyes absorb some of the photons flowing through the room, and that is how you see.

For instance, a photon in the visible spectrum would contain an energy of approximately 4 X (10 to the power of -19) joules Thus, a perfectly efficient 100-watt light bulb would emit approximately 2.5 X (10 to the power of 20) photons per second.

Use Maya Default IBL (Image Based Lighting)

Navigate to the following location:

C:\Program Files\Autodesk\Maya2018\presets\Assets\IBL\

And Choose either:

Interior 1 – color

Interior 1 – Neutral

Interior 2 – color

Interior 2 – Neutral

Exterior 1 – color

Exterior 1 – Neutral

Exterior 2 – color

Exterior 2 – Neutral

OR Download a “Cool” HDRI file.

It should look something like this . . .
  • Make a Table.
  • Create new Camera, label it RENDER_ME & look through it.
  • Add image based lighting - HDR Image, Hide in image in render.
  • Turn off opaque for both the glass and the OJ
The juice is overlapping the glass just by a tad, so we are going to scale it down just a bit.  First we are going to change the pivot point so it scales evenly.  Select the revolved liquid geometry and choose Modify > Center Pivot.  We also have to delete the history on the geometry so that the old curve does not control it anymore. Select the geometry, Edit >  Delete by Type > History.  Now while it is still selected, uniformly scale it to 0.99 units in Scale X, Y, & Z.