alternative formules

here alternative formules:
```
float determinant(mat2 m) {
return cross(vec3(m[0],0),vec3(m[1],0)).z;
}
float determinant(mat3 m) {
return dot(m[0],cross(m[1],m[2]));
}
float determinant(mat4 m) {
vec4 b = vec4(determinant(mat3(m[1].yzw,m[2].yzw,m[3].yzw)),
-determinant(mat3(m[1].xzw,m[2].xzw,m[3].xzw)),
determinant(mat3(m[1].xyw,m[2].xyw,m[3].xyw)).
-determinant(mat3(m[1].xyz,m[2].xyz,m[3].xyz)));
return dot(m[0],b);
}
```
I hope you like it like me :)
Regards,
Antonino

The issue names no files, tests, or entry points. Start by locating the current determinant implementation in the repository and compare it with the supplied GLSL formulas; completion criteria are not stated, so confirm the expected implementation and validation with the maintainer.

Written by the indexing model from the issue text.