+
+void demo_abort(void)
+{
+ set_text_mode();
+ stop_logger();
+ printf("demo_abort called. see demo.log for details. Last lines:\n\n");
+ print_tail("demo.log");
+ abort();
+}
+
+#define TX(ev) ((ev)->motion.motion[0])
+#define TY(ev) ((ev)->motion.motion[1])
+#define TZ(ev) ((ev)->motion.motion[2])
+#define RX(ev) ((ev)->motion.motion[3])
+#define RY(ev) ((ev)->motion.motion[4])
+#define RZ(ev) ((ev)->motion.motion[5])
+
+static int handle_sball_event(sball_event *ev)
+{
+ switch(ev->type) {
+ case SBALL_EV_MOTION:
+ if(RX(ev) | RY(ev) | RZ(ev)) {
+ float rx = (float)RX(ev);
+ float ry = (float)RY(ev);
+ float rz = (float)RZ(ev);
+ float axis_len = sqrt(rx * rx + ry * ry + rz * rz);
+ if(axis_len > 0.0) {
+ rot = quat_rotate(rot, axis_len * 0.001, -rx / axis_len,
+ -ry / axis_len, -rz / axis_len);
+ }
+ }
+
+ pos.x += TX(ev) * 0.001;
+ pos.y += TY(ev) * 0.001;
+ pos.z += TZ(ev) * 0.001;
+ break;
+
+ case SBALL_EV_BUTTON:
+ if(ev->button.pressed) {
+ pos = v3_cons(0, 0, 0);
+ rot = quat_cons(1, 0, 0, 0);
+ }
+ break;
+ }
+
+ return 0;
+}
+
+void recalc_sball_matrix(float *xform)
+{
+ quat_to_mat(xform, rot);
+ xform[12] = pos.x;
+ xform[13] = pos.y;
+ xform[14] = pos.z;
+}