Moving UV in BGE

Question

After watching many tutorials I've bumped into one from which i've learned that it is possible to move UV unwrap over the texture. And the .py looks like below:

import bge
cont = bge.logic.getCurrentController()
own = cont.owner
mesh = own.meshes[0]
verts = mesh.getVertexArrayLength(0)
for i in range(0, verts):
    point = mesh.getVertex(0, i)
    uv = point.getUV()
    uv[0] += own['x']/100
    uv[1] += own['y']/100
    point.setUV(uv)

Wanted to ask is there a way of how to move individual vertex points in a similar manner?

Many thanks in advance.

Noob

Answer 1

The code you show goes trough every vertex then manipulate it. To manipulate a single vertex, you just have to "skip" the for loop ; something like that :

import bge
cont = bge.logic.getCurrentController()
own = cont.owner
mesh = own.meshes[0]
# verts = mesh.getVertexArrayLength(0) #we don't need that anymore

i = 0 #the index of the vertex we want to manipulate. 0 is the first one
point = mesh.getVertex(0, i)
uv = point.getUV()
uv[0] += own['x']/100
uv[1] += own['y']/100
point.setUV(uv)

i = 1 #the index of the vertex we want to manipulate. 1 is the second one
point = mesh.getVertex(0, i)
uv = point.getUV()
uv[0] += own['x']/100
uv[1] += own['y']/100
point.setUV(uv)

# ...and repeat with i=2, i=3 etc

This code should work (i can't test it right now), but is not very robust. What appends if you try to manipulate a vertex that doesn't exist ?

As the code repeats a lot, you can wrap some of it in a function, like that :

import bge
cont = bge.logic.getCurrentController()
own = cont.owner
mesh = own.meshes[0]

move_uv(0, 0.5, 0.0)  #move the first vertex 0.5 right
move_uv(1, 0.0, -0.5) #move the second vertex 0.5 down
move_uv(2, 0.1, -0.1) #... and so on

def move_uv(index, moveX, moveY):
    point = mesh.getVertex(0, index)
    uv = point.getUV()
    uv[0] += moveX
    uv[1] += moveY
    point.setUV(uv)