Recent content by Artlav

Real physics, ye cruel thing, you took away my starbow? Then here is my starsmile, adherent fully to your code. ( Going perpendicular to the galaxy at 0.8c ) No, certainly not. I only got the idea to add relativity a few week ago.

Starbow, hm? Oddly enough, that's exactly the kind of an effect i got at first, and felt that it's pretty, but unrealistic. Got the article, it's pretty much exactly what i was looking for. Turns out i got most of the things right on the second try, except for the intensity factor - it's not...

But will the temperature be anywhere near survivable? The thought that piqued my curiosity was that there could be a longer-than-instant period where such survivable conditions could exist inside such a collapsing nebula.

I take the frequencies of red, green and blue, doppler shift them, convert each result back to RGB, then mix in the same proportion than in the original. This gives odd results for random colors, but works ok for near-white ones the stars tend to have. If you know of a better way, i'd like to...

I'm trying to render the sky as it would appear from a starship moving at some large part of the speed of light. Geometry was straightforward, but colors are the problem. How would the doppler effect change the color of a star? The expectation is that the stars behind are red and the ones ahead...

I have been reading about and contemplating the early stages of star formation lately. An interstellar cloud collapses under it's own gravity to form a star. There is much data about what could trigger it, and what happens when the gas heats up or starts fusing. However, i couldn't find...

Ah. Skew rays was the googleable term i was looking for. Thanks. I'm just exploring what can be done with raytracing, making one myself. Since it's not for anything important or for profit, i find it more valuable to (re-)invent things myself rather than look at things already done and figured...

Imagine a lens in front of you, on a table you're sitting at. It's at an angle to you. Look at it's center. Now shift that line of sight to the side. You will get a ray that passes through a lens, and yet it's not coplanar with the axis of the lens (the line that is perpendicular to the plane of...

Greetings. I'm working on a raytracer, and got stuck with trying to model a lens analytically. Given is a thin lens at position p with the axis n, radius r and a focal distance f, a ray hits it at position p1 going in the direction d. Which way would the ray be going on the other side of the...

There is an article on procedural texture generation by example. I'm trying to implement it, and got lost in the mathematics. http://graphics.cs.kuleuven.be/publications/LVLD10PISTE/ The outline of the algorithm is thus: We start with a noise-like photo. Do a 2D DFT of it: Compute the power...

I know. But that is not what the question is about.

It's a centrifugal "pump" like the image below, used to fill up air mattresses. It produces a lot of air flow, but almost no pressure. That is, it can quickly inflate a garbage bag, but won't force any air into a regular party balloon. The latter is what i was thinking of using it for.

Let's say i have an air pump which produce plenty of air flow, but almost no pressure. Is there a simple way to turn this high flow, low pressure into high pressure, low flow? I'm thinking something akin to a gearbox turning fast spin, low torque of a motor into a high torque, slow spin output...

Hm, interesting. Two directions then. First, how do you compute it for a helium atom, even approximately? I'm looking for key words. Second, is there enough empirical data to calculate a refractive index for common gasses at given conditions? I found data sets online (i.e...

Hello. Is there a way to calculate properties of a gas, given only it's composition? I.e. let's say i want to know what would a planet look like with an atmosphere of a mix of 50% gaseous sulphur and 50% gaseous mercury, at 500*C and surface pressure of half that of Earth. How would i go about...