rolling back (most of) lua 5.2 compatibility patches. hopefully that will unbreak unC0Rr's lua issues for now.
attribute vec2 vertex;
attribute vec2 texcoord;
attribute vec4 colors;
varying vec2 tex;
uniform mat4 mvp;
void main()
{
vec4 p = mvp * vec4(vertex, 0.0, 1.0);
gl_Position = p;
tex = texcoord;
}