examples: improve the pendulum simulation, with several modes and diagrams (#13446)

examples/pendulum-simulation/modules/sim/params_test.v

@@ -0,0 +1,125 @@
+module sim
+
+import math
+
+const (
+	params_test_mock_params = SimParams{
+		rope_length: 0.25
+		bearing_mass: 0.03
+		magnet_spacing: 0.05
+		magnet_height: 0.03
+		magnet_strength: 10
+		gravity: 4.9
+	}
+	params_test_mock_state = SimState{
+		position: vector(
+			x: -0.016957230930171364
+			y: -0.02937078552673521
+			z: 0.002311063475327252
+		)
+		velocity: vector(
+			x: -7.251158929833104
+			y: -12.559375680227724
+			z: -105.91539687686381
+		)
+		accel: vector(
+			x: -8.337034766251843e-11
+			y: -2.842170943040401e-10
+			z: 1.2126596023639044e-10
+		)
+	}
+	params_test_mock_tetha = 2.0 * math.pi / 3.0
+)
+
+pub fn test_get_rope_vector() {
+	result := sim.params_test_mock_params.get_rope_vector(sim.params_test_mock_state)
+	expected := vector(
+		x: -0.016957230930171364
+		y: -0.02937078552673521
+		z: -0.24768893652467275
+	)
+	assert result == expected
+}
+
+pub fn test_get_forces_sum() {
+	result := sim.params_test_mock_params.get_forces_sum(sim.params_test_mock_state)
+	expected := vector(
+		x: 3.637978807091713e-12
+		y: 5.229594535194337e-12
+		z: 9.094947017729282e-13
+	)
+	assert result == expected
+}
+
+pub fn test_get_grav_force() {
+	result := sim.params_test_mock_params.get_grav_force(sim.params_test_mock_state)
+	expected := vector(
+		z: -0.147
+	)
+	assert result == expected
+}
+
+pub fn test_get_magnet_position() {
+	result := sim.params_test_mock_params.get_magnet_position(sim.params_test_mock_tetha)
+	expected := vector(
+		x: -0.024999999999999988
+		y: 0.043301270189221946
+		z: -0.03
+	)
+	assert result == expected
+}
+
+pub fn test_get_magnet_force() {
+	result := sim.params_test_mock_params.get_magnet_force(sim.params_test_mock_tetha,
+		sim.params_test_mock_state)
+	expected := vector(
+		x: -157.45722976925555
+		y: 1422.736432604726
+		z: -632.5695169850264
+	)
+	assert result == expected
+}
+
+pub fn test_get_magnet_dist() {
+	result := sim.params_test_mock_params.get_magnet_dist(sim.params_test_mock_tetha,
+		sim.params_test_mock_state)
+	expected := 0.07993696666249227
+	assert result == expected
+}
+
+pub fn test_get_magnet1_force() {
+	result := sim.params_test_mock_params.get_magnet1_force(sim.params_test_mock_state)
+	expected := vector(
+		x: 1310.8545084099674
+		y: 575.0062553126633
+		z: -632.5695169850262
+	)
+	assert result == expected
+}
+
+pub fn test_get_magnet2_force() {
+	result := sim.params_test_mock_params.get_magnet2_force(sim.params_test_mock_state)
+	expected := vector(
+		x: -157.45722976925555
+		y: 1422.736432604726
+		z: -632.5695169850264
+	)
+	assert result == expected
+}
+
+pub fn test_get_magnet3_force() {
+	result := sim.params_test_mock_params.get_magnet3_force(sim.params_test_mock_state)
+	expected := vector(
+		x: -1710.46541088048
+		y: -2962.612996234165
+		z: -6871.632889552589
+	)
+	assert result == expected
+}
+
+pub fn test_get_tension_force() {
+	result := sim.params_test_mock_params.get_tension_force(sim.params_test_mock_state,
+		vector(x: 0.0, y: 0.0, z: 0.0))
+	expected := vector(x: 0.0, y: 0.0, z: 0.0)
+	assert result == expected
+}