## Search found 9 matches

Thu Feb 02, 2017 8:49 pm
Forum: General Development
Topic: Intersection of ray with quadric surface for hobby ray tracer
Replies: 6
Views: 3903

### Re: Intersection of ray with quadric surface for hobby ray tracer

Thanks a lot! I'm still testing, but it started to work now.
Also found relatively simple and compact ref here: https://people.cs.clemson.edu/~dhouse/c ... adrics.pdf
My next challenge is solid constructions.
Fri Jan 20, 2017 7:48 pm
Forum: General Development
Topic: Intersection of ray with quadric surface for hobby ray tracer
Replies: 6
Views: 3903

### Intersection of ray with quadric surface for hobby ray tracer

I'm looking into ways to add more shapes to my hobby path tracer, such as cylinder, cone, ellipse. So, I'm at this reference: http://www.bmsc.washington.edu/people/merritt/graphics/quadrics.html which is taken from Lindley book on ray tracing (which I also have, but without CD). It briefly explains ...
Mon Apr 11, 2016 4:23 pm
Forum: Visuals
Topic: Just came out of my hobby path tracer this morning
Replies: 2
Views: 3899

### Just came out of my hobby path tracer this morning

Code is so basic it is waste to share, yet image is so beautiful to me.
Thu Mar 17, 2016 4:42 pm
Forum: General Development
Topic: Energy conservation vs. energy normalization
Replies: 4
Views: 3865

### Re: Energy conservation vs. energy normalization

So, I'm looking in close to right direction. Thanks for your help.
Thu Mar 17, 2016 1:28 am
Forum: General Development
Topic: Energy conservation vs. energy normalization
Replies: 4
Views: 3865

### Energy conservation vs. energy normalization

I'm slowly (like 10 lines per week:) ) finishing my hobby path tracer and bit stuck with BRDFs. My current understanding is that BRDF functions are normalized with reflected ray equal to surface normal, and this, for instance, gives (2+n)/(2+pi) factor for Phong model. Yet, this is not energy conver...
Wed Jan 06, 2016 5:38 pm
Forum: General Development
Topic: Basic question: reflections with glass sphere
Replies: 2
Views: 4333

### Re: Basic question: reflections with glass sphere

Thanks for help, it works now. I changed color values of surfaces to lower values (say from {1, 1, 1} to {0.1, 0.1, 0.1} for white) and the reflection popped up.
Wed Jan 06, 2016 12:12 am
Forum: General Development
Topic: Basic question: reflections with glass sphere
Replies: 2
Views: 4333

### Basic question: reflections with glass sphere

I'm having issue comparing how light is reflected in my hobby ray tracer and real life for a transparent glass sphere. As I understand, all the light reflected from a glass sphere is due to Fresnel reflection and so for highlighted on the image area it should be (where appears angle is less than 20 ...
Fri Oct 30, 2015 7:26 pm
Forum: Visuals
Topic: Glitch Pictures anyone?
Replies: 75
Views: 85846

### Re: Glitch Pictures anyone?

Here is mine, with ray hit calculation 2 issues which I'm working on now in my hobby ray tracer: (1) sometimes rays go through the wall, this issue is caused by a difference in calculation method of distance in triangle intersection and kd-tree (at least this is my current understanding of it). the ...
Tue Oct 27, 2015 4:03 pm
Forum: General Development
Topic: Basic question: material that will change the normal
Replies: 3
Views: 6002

### Re: Basic question: material that will change the normal

GetNormal(uv...) could return final corrected (based on material) normal. Then this normal could be used for each of mentioned calculations (not sure about shadows, but possibly as minor optimization of hit test).