Ray Tracer Part 5: Reflection

Single Reflection Ray on Mirrored Sphere

This assignment's focus was adding reflection to the Ray Tracer. Due to the size of my floor, I moved the reflective sphere around a little for a more aesthetic reflection. I also moved the light sources slightly to the center so the shadows would reflect in the back sphere.

I also implemented using multiple reflection rays to approximate a BRDF. Below you can see the results of some of these experiments.

 

6 reflection rays, in a cone-radius
of .005



8 reflection rays, with a cone-radius of .01



8 reflection rays, with a cone-radius
 of .005


 

Dandelions - Getting the Dome

Its weird how just seemingly small concepts can move you from having something look weird to looking about right. It's not perfect, but it makes you feel on the right track. This is the path to making the dandelion move from a wad of cotton balls on sticks to something looking like a dandelion.

First off, I created randomly generated (and removed) dandelions to go into my field. Each one a separate and new instance of a flower.

 

The next step was to try and figure out how to make it a little more realistic. After some exciting searching and browsing pictures of dandelions, I tried to make the colors of the different elements closer to what they actually were. I learned that the stalks of each flower were more orangey, and the seedlet stalks were a darker green. I also shrank the size of the balls on the tips of each seedlet. Then, enter the hairs. They aren't curved yet, but standing straight still created a nice effect.

 



 

After further research, I decided to make the spheres of the flower closer to the dome-like structure the dandelions seem to have. From playing around with how the dome should act, I got to a point resulting like this:

 



I liked the domey-ness, and decided to keep up with this a bit longer. The below images are at a smaller geodesic tessellation to better see what the structure of the dandelions looks like.

Ray Tracer Part 4 - Procedural Shading

For this assignment, we had to add a pattern/texture to the floor of the scene. At different points of intersection, the floor is now different colors.

Initially, the pattern was a checkered Red/Yellow floor, as shown below:

Afterwards, as an "extra", I added another pattern. Now the pattern on the floor is a diagonal, as shown below.

I also allowed for an easy way to make the stripes and grid go at smaller and larger sizes, as shown below.

Ray Tracer Part 3 - Shading

Phong Illumination on Scene

The purpose of this assignment was to implement the Phong Illumination model in the ray tracer assignment. In this picture there are 3 light models (format: (r, g, b, intensity)):

ambient ( 1, 1, 1, .2 ) 

diffuse ( .4, .4, .4, 1 ) 

specular ( 1, 1, 1, 1

For an "Extra", I implemented another Light Source. 

To show the differences with the different light sources and experiment with colors, I made the spheres an off-white (0.9, 0.9, 0.9). The Normal light source is the same as the light source above. The new light sources have the following model specifications: 

Red Light 
specular ( 1, 0, 0, 1 )
diffuse ( 1, 0, 0, 1)

Green Light
diffuse ( 0, 1, 0, 1 )
specular ( 0, 1, 0, 1 )

Blue Light 
diffuse ( .1, .1, 1, 1 )
specular ( .1, .1, 1, 1 )

3 light sources, Red, Green, and Blue

Red and Normal light

Blue and Normal light

Red and Blue, with Normal Light

Dandelion - Starting Points and Seedlets

Dandelion with seedlet stalks and the geodesic sphere
they are created on, 3 tessellations.

The first pieces of this project have come through, with a basic dandelion structure to be replicated by user command. There is a simple expandable / contractible field for the dandelion(s) to sit on, along with a single dandelion placed in the front left corner. This dandelion has a head created by a tessellated (geodesic) sphere. The user can increase the number of seedlets on the dandelion by increasing the number of tessellations. In the pictures, you can see the tessellations of 2 and 3.

From researching dandelions, I learned that they have fractal qualities to them, as they are structured around in a geodesic dome. I used this quality to structure the even spaces between each seedlet stalk. At each point on the sphere, I created a stalk back to the center of the dandelion.

Some changes that need to happen is for this to happen on a dome instead of a sphere. I'll need to cut off the bottom of the sphere to create that effect. Dandelions have a small "platform" in their center, not a ball. I also need to generate a thicker stalk for each seedlet.

At the tip of the seedlets are a base (a simple gluSphere for now) for the individual hairs that will stick out for a "furry" appearance that the dandelions have.

A basic camera is set up for viewing the field. It can be controlled with W, A, S, D. The field can be increased with J, and decreased with K.

The next step is creating multiple dandelions on demand, as well as setting up cameras for each individual dandelion.

Dandelion with seedlet stalks, without geodesic
sphere, and 2 tessellations.

Dandelion with seedlet stalks without the sphere
structure. With 3 tessellations.

Ray Tracer Pt 3 : Basic Shading

Phong Illumination / Shading

The purpose of this assignment was to implement the Phong Illumination model in the ray tracer assignment. In this picture there are 3 light models (format: (r, g, b, intensity)) ambient(1, 1, 1, .2), diffuse(0, .3, .3, .6), and specular(1, 1, 1, 1).

For an "Extra", I implemented another Light Source. 

To show the differences with the different light sources and experiment with colors, I made the spheres white. The new light source has the following model specifications: specular(0, .4, .4, 1) and diffuse(.4, .4, 0, 1). The first image is both light sources, and below that are each light source alone.

Both Light Sources

Light Source #2

Light Source #1