# Stackmann0

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1. ## How to get the 3D position for the point with (0,0) UV coordinates?

I think I understand now.. the solution posted in the thread post is indeed correct. Thank you @lawnjelly and @l0calh05t for your explanations
2. ## How to get the 3D position for the point with (0,0) UV coordinates?

I don't think that its correct. I mean, you can search for the triangle in UV space that has (x,y) (the point in uv space we're trying to find its 3d pos) inside it. But then, the fact of using barycentric coords of that point to find the 3D pos doesn't sound correct to me as the mapping between the triangles (the one in UV space and the one in 3D space) is not involved.. So, I don't know if there is a solution to this problem in the general case as you mentioned in your second reply.. or maybe I'm missing something or confusing things
3. ## 3D How to get the 3D position for the point with (0,0) UV coordinates?

Hello, I have a 3D triangular mesh(vertices, indices, uv coords) that I'm rendering to the screen. Let's assume that the UV mapping is one-to-one. I'm trying to find a way to find the 3D position of the point with UV coordinates equal to (0,0). I searched the internet but I only find answers that I don't find convincing. The solution that I found: - Find, in UV space, the triangle that contains (0,0).. let's call it T - Calculate barycentric coordinates for (0,0) with respect to T - interpolate the 3D positions of T's vertices using barycentric coords to get the result. this seems wrong to me. Here's why: Let M be the mapping between 3D space and UV space that associates UV coords for every vertex. Let A,B and C be the vertices of T. Let P be the origin of UV space ( P = (0,0) ). We have P = alpha*A + beta*B + gamma*C (alpha,beta and gamma are the barycentric coords of P with respect to T). We assumed the UV mapping to be one-to-one, so let M° be the inverse of M. We have : M°(P) = M°(alpha*A + beta*B + gamma*C) The solution in question assumes that M° is linear.. if that was the case you can have: M°(P) = alpha*M°(A) + beta*M°(B) + gamma*M°(C) But that is not the case (correct me if I'm wrong). So is there a way to find the 3D position of a point with specific UV coords? Thanks in advance.
4. ## [ANDROID + TRAILER] Jelly Couple: control two jellies at the same time

Hello guys, Today we launched our first game on Android: Jelly Couple. It's a game where you control a couple of jellies that can jump,crouch and flip gravity. You control them at the same time while trying to avoid deadly spikes.    Here's a gameplay video :   Link to play store : http://bit.ly/JELLYCOUPLE   What do you think guys?