static void paint_normal_and_height_maps(float min, float max)
{
int f, i, j;
float rad;
char red, green, blue;
int p;
for (f = 0; f < 6; f++) {
for (i = 0; i < DIM; i++) {
for (j = 0; j < DIM; j++) {
p = (j * DIM + i) * 4;
rad = vec3_magnitude(&vertex[f][i][j]);
rad = (rad - min) / (max - min);
heightmap_image[f][p + 0] = (unsigned char) (255.0 * rad);
heightmap_image[f][p + 1] = (unsigned char) (255.0 * rad);
heightmap_image[f][p + 2] = (unsigned char) (255.0 * rad);
heightmap_image[f][p + 3] = 255;
if (rad > sealevel) {
red = normal[f][i][j].v.x * 255;
green = normal[f][i][j].v.y * 255;
blue = normal[f][i][j].v.z * 255;
normal_image[f][p + 0] = red;
normal_image[f][p + 1] = green;
normal_image[f][p + 2] = blue;
} else {
normal_image[f][p + 0] = 127;
normal_image[f][p + 1] = 127;
normal_image[f][p + 2] = 255;
}
normal_image[f][p + 3] = 255;
}
}
}
}
void set_light(t_vec3 hit, t_obj *obj, t_lgt *light)
{
double theta;
double epsilon;
light->ray.pos = hit;
if (light->type == DIRECTIONAL)
{
light->ray.dir = vec3_fmul(light->dir, -1);
obj->dist_attenuation = 1.0;
}
else
{
light->ray.dir = vec3_sub(light->pos, hit);
obj->t = vec3_magnitude(light->ray.dir);
obj->dist_attenuation = (1.0 + obj->t * obj->t * light->attenuation);
}
if (light->type == SPOT)
{
theta = vec3_dot(light->dir, vec3_norm(vec3_fmul(light->ray.dir, -1)));
epsilon = light->cutoff - light->cutoff_outer;
light->cutoff_intensity = ft_clampf((theta - light->cutoff_outer) /
epsilon, 0, 1);
}
vec3_normalize(&light->ray.dir);
}
void plane_normalize(plane_t *p)
{
float len = 1.f / vec3_magnitude(&p->normal);
vec3_scale(&p->normal, len);
p->dist *= len;
}
void quat_vector_vector(quat_t *q, const vec3_t *a, const vec3_t *b)
{
float cost = vec3_dot(a, b);
if (cost > 0.99999f) {
/* parallel */
*q = QUAT_IDENT;
} else if (cost < -0.99999f) {
/* opposite */
vec3_t t = VEC3(0, a->x, -a->y); /* cross with (1,0,0) */
if (vec3_magnitude(&t) < EPSILON)
t = VEC3(-a->z, 0, a->x); /* nope, use (0,1,0) */
vec3_normalize(&t);
q->v = t;
q->w = 0.f;
} else {
vec3_t t;
vec3_cross(&t, a, b);
vec3_normalize(&t);
/* sin^2 t = (1 - cos(2t)) / 2 */
float ss = sqrt(.5f * (1.f - cost));
vec3_scale(&t, ss);
q->v = t;
/* cos^2 t = (1 + cos(2t) / 2 */
q->w = sqrt(.5f * (1.f + cost));
}
}
/**
* Component of the support function for a cylinder collider.
**/
static void
object_support_component_cylinder(object_t *object,
float direction[3], float out[3])
{
float top[3] = { 0, object->h / 2, 0 };
float bottom[3] = { 0, -object->h / 2, 0 };
float axis[3];
float dir_perp[3];
float trans[16];
float dot_top;
object_get_transform_mat(object, trans);
/* Top and bottom are set to points in the middle of the top and the
* bottom faces of the cylinder respectively. We transform them to
* their worldspace positions.
*/
matrix_vec3_mul(trans, top, 1.0, top);
matrix_vec3_mul(trans, bottom, 1.0, bottom);
/* We get an axis vector that runs down the middle of the cylinder. */
vec3_subtract(top, bottom, axis);
/* Part of another process, but useful now for a reason... */
vec3_cross(axis, direction, dir_perp);
/* If the cross product is zero, our direction is aligned with the
* cylinder and top and bottom are our two final candidates.
*/
if (vec3_magnitude(dir_perp) > 0) {
/* This completes what we started with the last cross product.
* dir_perp is now a vector perpendicular to the cylinder's
* axis, but as close to our selected direction as possible.
*/
vec3_cross(dir_perp, axis, dir_perp);
/* Scale dir_perp to be the radius of our cylinder.
*/
vec3_normalize(dir_perp, dir_perp);
vec3_scale(dir_perp, dir_perp, object->r);
/* Finally, move top and bottom to the edges of our cylinder in
* the appropriate direction. We now have our two final
* candidates.
*/
vec3_add(dir_perp, top, top);
vec3_add(dir_perp, bottom, bottom);
}
/* We now have two candidates, top and bottom. We can just use largest
* dot product to determine which is furthest.
*/
dot_top = vec3_dot(top, direction);
if (dot_top > vec3_dot(bottom, direction))
memcpy(out, top, 3 * sizeof(float));
else
memcpy(out, bottom, 3 * sizeof(float));
}
t_vect3d vec3_norm(t_vect3d v3)
{
float magnitude;
t_vect3d r;
magnitude = vec3_magnitude(v3);
r.x = v3.x / magnitude;
r.y = v3.y / magnitude;
r.z = v3.z / magnitude;
return (r);
}
void vec3_normalize(vec3_t *v)
{
float len = vec3_magnitude(v);
if (len < 1.e-5)
return;
len = 1.f / len;
vec3_scale(v, len);
}
t_vec3 bump_normal(t_obj *obj, t_ray *ray)
{
t_vec3 normal;
t_vec3 tangent;
t_vec3 binormal;
t_vec3 bump;
t_vec3 c[2];
normal = obj->normal;
bump = texture_mapping(obj, obj->mat.texture.bump, ray->hit);
bump = vec3_sub(vec3_fmul(bump, 2), vec3(1, 1, 1));
c[0] = vec3_cross(normal, vec3(0, 0, 1));
c[1] = vec3_cross(normal, vec3(0, 1, 0));
tangent = (vec3_magnitude(c[0]) > vec3_magnitude(c[1]) ? c[0] : c[1]);
tangent = vec3_sub(tangent, vec3_fmul(normal, vec3_dot(tangent, normal)));
vec3_normalize(&tangent);
binormal = vec3_norm(vec3_cross(normal, tangent));
normal.x = vec3_dot(bump, vec3(tangent.x, binormal.x, normal.x));
normal.y = vec3_dot(bump, vec3(tangent.y, binormal.y, normal.y));
normal.z = vec3_dot(bump, vec3(tangent.z, binormal.z, normal.z));
vec3_normalize(&normal);
return (normal);
}
static void paint_terrain_colors(float min, float max)
{
int f, i, j;
float r, n;
int p;
for (f = 0; f < 6; f++) {
for (i = 0; i < DIM; i++) {
for (j = 0; j < DIM; j++) {
p = (j * DIM + i) * 4;
r = vec3_magnitude(&vertex[f][i][j]);
r = (r - min) / (max - min);
n = (noise[f][i][j] - minn) / (maxn - minn);
color_output(f, p, r, n);
}
}
}
}
static void paint_height_maps(float min, float max)
{
int f, i, j;
float r;
unsigned char c;
int p;
for (f = 0; f < 6; f++) {
for (i = 0; i < DIM; i++) {
for (j = 0; j < DIM; j++) {
p = (j * DIM + i) * 4;
r = vec3_magnitude(&vertex[f][i][j]);
r = (r - min) / (max - min);
c = (unsigned char) (r * 255.0f);
output_image[f][p + 0] = c;
output_image[f][p + 1] = c;
output_image[f][p + 2] = c;
output_image[f][p + 3] = 255;
}
}
}
}
static void find_min_max_height(float *min, float *max)
{
int f, i, j;
float mmin, mmax;
float h;
printf("Finding min and max height\n");
mmin = 1000000.0f;
mmax = 0.0f;
for (f = 0; f < 6; f++) {
for (i = 0; i < DIM; i++) {
for (j = 0; j < DIM; j++) {
h = vec3_magnitude(&vertex[f][i][j]);
if (h < mmin)
mmin = h;
if (h > mmax)
mmax = h;
}
}
}
*min = mmin;
*max = mmax;
}