Which is NOT one of the three methods that identify objects on the display?

The following shows an example of a swizzling operator. What will be the result of the following example?

vec4 a;

Which is NOT one of the convex polygons?

Which is the worst triangle to render?

The Sierpinski Gasket starts with a triangle. It connects bisectors of sides and removes the central triangle. This same process repeats. 

After four subdivisions,  which triangles of the following will be rendered? (One subdivision is the original triangle (one triangle) itself.)

What variables are described by the following?

These variables cannot be changed in shaders. They are constant for an entire primitive. However, they can be changed in an application and sent to shaders. They are used to pass information to shaders such as the time, a bounding box of a primitive, or transformation matrices.

What is described by the following?

This is one of the algorithms that remove hidden surfaces. This algorithm shows only those surfaces in front of other surfaces. This algorithm saves depth information as objects are rendered so that only the front objects appear in the image. The algorithm keeps track of the smallest depth value of those points which are seen from pixel (x, y). These depth values are stored in some buffer. 

What is described by the following?

No point in P is inside the circumcircle of any triangle for a given set P of discrete points in a plane.

What kind of object has the following characteristics?

As the object is being subdivided,

• the area goes to zero
• the perimeter goes to infinity

Who coined the term "fractal"?