got mandelbulbs working

main.c

@@ -5,7 +5,17 @@
 
 #define SCENE_MOD 2
 
-// this is the circle distance function definition
+
+/*
+
+    Infinite circle scene object
+
+    This circle repeats every SCENE_MOD units in all directions
+
+    It has some basic shading, calculation the hit angle and making shallower impacts darker
+
+*/
+
 double circle_dist(Point x, SceneObject *self) {
     double r = self->args[0];
     return pt_dist(pt_mod(x, SCENE_MOD), self->location) - r;
@@ -24,7 +34,7 @@ Color circle_color(Point hit, Point direction, SceneObject *self) {
 
     return color;
 }
-
+// constructs the scene object
 SceneObject circle_new(Point loc, double radius) {
     SceneObject so;
     so.location = loc;
@@ -37,16 +47,69 @@ SceneObject circle_new(Point loc, double radius) {
 }
 
 
-
+/*
+
+    Mandelbulb scene object
+
+    Currently cannot be set at a specific location, always resides at origin (0,0,0)
+
+    Color function is just a flat shader, detail is displayed with ambient occlusion
+
+*/
+double mandelbulb_dist(Point pt, SceneObject *self) {
+    int iters = self->args[0];
+    double power = self->args[1];
+
+    Point z = pt;
+	float dr = 1.0;
+	float r = 0.0;
+	for (int i = 0; i < iters ; i++) {
+		r = pt_length(z);
+		if (r>2) break;
+		
+		// convert to polar coordinates
+		float theta = acos(z.z/r);
+		float phi = atan2(z.y,z.x);
+		dr =  pow(r, power-1.0)*power*dr + 1.0;
+		
+		// scale and rotate the point
+		float zr = pow( r,power);
+		theta = theta*power;
+		phi = phi*power;
+		
+		// convert back to cartesian coordinates
+		z = pt_mult(pt_new(sin(theta)*cos(phi), sin(phi)*sin(theta), cos(theta)), zr);
+		pt_add(&z, pt);
+	}
+	
+    return 0.5*log(r)*r/dr;
+    
+}
+Color mandelbulb_color(Point hit, Point direction, SceneObject *self) {
+    return self->color;
+}
+// constructs the scene object
+SceneObject mandelbulb_new(Point location, int iters, double power) {
+    SceneObject so;
+    so.location = location;
+    so.args = malloc(sizeof(double) * 2);
+    so.args[0] = iters;         // iterations
+    so.args[1] = power;             // power
+    so.distance = mandelbulb_dist;
+    so.get_color = mandelbulb_color;
+    so.color = color_new(255,255,255);
+    return so;
+}
 
 int main(int argc, char* argv[]) {
     int threads = 1;
     Camera cam;
     cam.fov = 90;
 
-    float cam_position = 0;
+    float cam_position = 1.2;
-    camera_set_looking_at(&cam, pt_new(cam_position,cam_position,cam_position), pt_new(1,1,1));
+    camera_set_looking_at(&cam, pt_new(cam_position,cam_position,cam_position), pt_new(0,0,0));
 
+    // get thread count from command line
     if (argc > 1) {
         threads = atoi(argv[1]);
     }
@@ -54,16 +117,14 @@ int main(int argc, char* argv[]) {
     printf("threads: %d\n", threads);
 
     // create basic scene with up to 10 objects
-    Scene scene = scene_new(1920, 1080, 10);
+    Scene scene = scene_new(1000, 1000, 10);
-    scene.max_steps = 300;
+    scene.max_steps = 1000;
-    scene.threshold = 0.02;
+    scene.threshold = 0.0001;
-
-    scene_add_obj(&scene, circle_new(pt_new(SCENE_MOD / 2.0, SCENE_MOD/ 2.0, SCENE_MOD / 2.0), .2));
 
-    //scene_add_obj(&scene, circle_new(pt_new(0,2,0), 0.5));
+    //scene_add_obj(&scene, circle_new(pt_new(SCENE_MOD / 2.0, SCENE_MOD/ 2.0, SCENE_MOD / 2.0), .2));
-    //scene_add_obj(&scene, circle_new(pt_new(0,-2,0), 0.5));
-    //scene_add_obj(&scene, circle_new(pt_new(0,-4,0), 0.5));
 
+    scene_add_obj(&scene, mandelbulb2_new(pt_new(1,1,1), 2000, 3));
+    
     Image *img = render_scene(&scene, &cam, threads);
 
     image_save_bmp(*img, "render.bmp");

src/camera.c

@@ -149,6 +149,12 @@ void camera_iterate_rays_const_dist(Camera camera, int width, int height, int th
         // only render the lines this thread is responsible for
         if (y % threads != thread_id) continue;
         
+        // display progress in percent
+        if (y % (height / 100) == 0 && y != 0) {
+            printf("\r%02i%%", (y * 100) / height);
+            fflush(stdout);
+        }
+
         // actually iterate this line
         curr_pt = starting_point;
         for (int x = 0; x < width; x++) {

src/scene.c

@@ -105,11 +105,19 @@ Color march_ray(Point origin, Point direction, Scene* scene) {
     // check for a hit
     if (dist <= threshold) {
         // a hit!
+        #ifndef SCENE_NO_AM_OCC
+        
         double f = (steps / (double) scene->max_steps);
         f = f * f * f * f;
 
         Color c = closest_obj->get_color(pos, direction, closest_obj);
         return color_mix(c, color_new(0,0,0), f);
+        
+        #else
+        
+        return closest_obj->get_color(pos, direction, closest_obj);
+
+        #endif
 
     } else {
         // a miss :(