16,231 reputation
23465
bio website sam.zoy.org
location Paris, France
age 35
visits member for 3 years, 4 months
seen 6 hours ago

I live in Paris, France.

I work on video games (computers and consoles) for a living. I write free software and all kind of crazy shit for fun. My interests: image processing, video coding, rendering, game development, maths, physics, compression, cryptography.


Apr
1
answered How to use mocaps in your game if they don't loop smoothly?
Apr
1
awarded  Nice Answer
Mar
28
awarded  mathematics
Mar
27
answered How can I project a 3D point onto a 3D line?
Mar
27
comment Compute world position by walking N units along spline?
You should fix your variable names. If Distance is the alpha value, why not call it Alpha? And… what is Alpha, then?
Mar
27
answered Compute world position by walking N units along spline?
Mar
26
comment What is Vector Projection and what is it's use in games?
“Couldn't find a clear enough answer on Google.” Really? The first Google hits for me include vector projection in game development, vector projection in a maths tutorial, and vector operations for game programmers. Have you read them?
Mar
25
comment Which Unreal Engine 4 project files can I ignore in source control?
Yes, the engine needs a lot of modifications, and upstream UE is regularly merged into the repository.
Mar
24
comment How do I lerp between values that loop (such as hue or rotation)?
Dividing a vector by its length is called normalization. It ensures it has length 1. The len ? len : 1.0 part just avoids a division by zero, in the rare case that the mouse is placed exactly at the joint position. It could have been written: if (len != 0) dx /= len;.
Mar
23
answered How do I lerp between values that loop (such as hue or rotation)?
Mar
23
comment Compute cone angle (cos) given side and hypotenuse vectors at time 0 and world matrix at time 1
If your tests show no difference between Transform and TransformNormal, you are not testing enough :-) Try adding a translation part to your tranformation matrix.
Mar
23
answered Compute cone angle (cos) given side and hypotenuse vectors at time 0 and world matrix at time 1
Mar
22
comment Calculating the point(s) at which two moving objects are a certain distance from each other
Just a note: the code would be simpler if you did veld = e1.vel - e2.vel and used that variable everywhere instead of p, r, q and s.
Mar
21
answered Which Unreal Engine 4 project files can I ignore in source control?
Mar
19
answered Sweep collision between two moving spheres?
Mar
8
comment From Position/Target to Orientation/Elevation
I suppose you mean 2.6e-06. That is perfectly normal when doing computations with floating point numbers. You can get slightly better precision using double instead of float, but I see little reason to aim for that: a difference of 2.6e-06 in the camera orientation is a displacement smaller than a thousandth of a pixel.
Mar
7
comment From Position/Target to Orientation/Elevation
Ah. If you switch Y and Z, the first argument to the second atan2 call should become dy.
Mar
7
comment From Position/Target to Orientation/Elevation
Well, swapping dy and dz is the way to go. Maybe you’re not converting radians back to degrees?
Mar
6
revised From Position/Target to Orientation/Elevation
nicer code
Mar
6
answered From Position/Target to Orientation/Elevation