X-Git-Url: https://eleni.mutantstargoat.com/git/?p=hair;a=blobdiff_plain;f=src%2Fhair.cc;h=b2eb4a058f2731d3ffa216ec7dbc1f3d7000a6cb;hp=c86044b56494737809c461e475635c47e3fb7239;hb=8efb44efc8830ffc5ae8eb387926f8b4fd00fb6e;hpb=b07896ffc92093a3e8adb4953d22927a5874e43d

diff --git a/src/hair.cc b/src/hair.cc
index c86044b..b2eb4a0 100644
--- a/src/hair.cc
+++ b/src/hair.cc
@@ -185,8 +185,43 @@ void Hair::update(float dt)
 
 		Vec3 accel = force; /* mass 1 */
 		hair[i].velocity += ((-hair[i].velocity * DAMPING) + accel) * dt;
-		hair[i].pos += hair[i].velocity * dt;
+		Vec3 new_pos = hair[i].pos + hair[i].velocity * dt;
+
+		/* collision detection with the head */
+		Vec3 normal = xform.upper3x3() * hair[i].spawn_dir;
+		Vec3 root = xform * hair[i].spawn_pt;
+		Vec3 dir = new_pos - root;
+		
+		normal.normalize();
+
+		/* angle that will cause the hair to be rendered inside the head */
+		float d = dot(dir, normal);
+		if(d < 0) {
+			new_pos += -d * normal;
+		}
+
+		hair[i].pos = handle_collision(new_pos);
 
 		dbg_force = force;
 	}
 }
+
+void Hair::add_collider(CollSphere *cobj) {
+	colliders.push_back(cobj);
+}
+
+Vec3 Hair::handle_collision(const Vec3 &v) const
+{
+	/* if we transform the center and the radius of the collider sphere
+	 * we might end up with a spheroid, so better just multiply the 
+	 * position with the inverse transform before check for collisions :*/
+
+	Vec3 new_v = inverse(xform) * v;
+
+	for(size_t i=0; i<colliders.size(); i++) {
+		if(colliders[i]->contains(new_v)) {
+			new_v = colliders[i]->project_surf(new_v);
+		}
+	}
+	return xform * new_v;
+}