Latest compatible version of Classicube from the original GitHub repository (https://github.com/ClassiCube/ClassiCube) that can be compiled on Classicube for PowerMac PPC running Mac OS X 10.4.

misc/wiiu/vs_coloured.glsl

@@ -0,0 +1,9 @@
+attribute vec3 in_pos;
+attribute vec4 in_col;
+varying vec4 out_col;
+uniform mat4 mvp;
+
+void main() {
+  gl_Position = mvp * vec4(in_pos, 1.0);
+  out_col = in_col;
+}