void proj_tests(void){
mat4_t m = mat4_look_at(vec4_new(0, 0, 5, 0),
vec4_new(0, 0, 0, 0), vec4_new(0, 1, 0, 0));
printf("Look at matrix:\n");
mat4_print(m);
m = mat4_ortho(-1, 1, -1, 1, 1, 100);
printf("ortho matrix:\n");
mat4_print(m);
m = mat4_perspective(90, 1, 1, 100);
printf("perspective:\n");
mat4_print(m);
}
void fixview(mat4 viewmatrix)
{
//a X b = [ay*bz - az*by, az*bx-ax*bz, ax*by-ay*bx]
float norm;
float cx = 1.0;
float cy = 2.0;
float cz = 3.0;
//uvn.n = front
float nx = 0.0-cx;
float ny = 10.0-cy;
float nz = 0.0-cz;
norm = sqrt(nx*nx + ny*ny + nz*nz);
nx /= norm;
ny /= norm;
nz /= norm;
//uvn.u = right = cross(front,(0,0,1))
float ux = ny*1 - nz*0;
float uy = nz*0 - nx*1;
float uz = nx*0 - ny*0;
norm = sqrt(ux*ux + uy*uy + uz*uz);
ux /= norm;
uy /= norm;
uz /= norm;
//uvn.v = above = cross(right, front)
float vx = uy*nz - uz*ny;
float vy = uz*nx - ux*nz;
float vz = ux*ny - uy*nx;
norm = sqrt(vx*vx + vy*vy + vz*vz);
vx /= norm;
vy /= norm;
vz /= norm;
viewmatrix[0][0] = ux;
viewmatrix[0][1] = uy;
viewmatrix[0][2] = uz;
viewmatrix[0][3] = -cx*ux - cy*uy - cz*uz;
viewmatrix[1][0] = vx;
viewmatrix[1][1] = vy;
viewmatrix[1][2] = vz;
viewmatrix[1][3] = -cx*vx - cy*vy - cz*vz;
viewmatrix[2][0] = -nx;
viewmatrix[2][1] = -ny;
viewmatrix[2][2] = -nz;
viewmatrix[2][3] = cx*nx + cy*ny + cz*nz;
viewmatrix[3][0] = 0.0f;
viewmatrix[3][1] = 0.0f;
viewmatrix[3][2] = 0.0f;
viewmatrix[3][3] = 1.0f;
mat4_print(viewmatrix);
}
void basic_test(void){
float ALIGN_16 a_rows[16] = {
1, 5, 0, 0,
2, 1, 3, 5,
6, 9, 0, 2,
5, 3, 8, 9
};
float ALIGN_16 b_rows[16] = {
4, 0, 2, 0,
1, 2, 7, 1,
0, 0, 2, 0,
1, 2, 0, 1
};
mat4_t a = mat4_from_rows(a_rows);
mat4_t b = mat4_from_rows(b_rows);
printf("Multiplying a:\n");
mat4_print(a);
printf("With b:\n");
mat4_print(b);
printf("Multiplication result:\n");
a = mat4_mult(a, b);
mat4_print(a);
vec4_t v = vec4_new(1, 2, 3, 1);
a = mat4_translate(v);
printf("translation matrix for [1, 2, 3]:\n");
mat4_print(a);
printf("Translated vector:\n");
v = mat4_vec_mult(a, v);
vec4_print(v);
a = mat4_rotate(90, vec4_new(1, 0, 0, 0));
printf("Rotation matrix:\n");
mat4_print(a);
v = mat4_vec_mult(a, vec4_new(0, 1, 0, 0));
printf("+Y vec rotated 90 deg about +X:\n");
vec4_print(v);
}