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-rw-r--r--tests/test_random_number_generator.h192
1 files changed, 178 insertions, 14 deletions
diff --git a/tests/test_random_number_generator.h b/tests/test_random_number_generator.h
index 50ad5ee362..39c4771c19 100644
--- a/tests/test_random_number_generator.h
+++ b/tests/test_random_number_generator.h
@@ -5,8 +5,8 @@
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
-/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
-/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md). */
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
@@ -36,18 +36,162 @@
namespace TestRandomNumberGenerator {
+TEST_CASE("[RandomNumberGenerator] Float") {
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ rng->set_seed(0);
+
+ INFO("Should give float between 0.0 and 1.0.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n = rng->randf();
+ CHECK(n >= 0.0);
+ CHECK(n <= 1.0);
+ }
+}
+
+TEST_CASE("[RandomNumberGenerator] Integer range via modulo") {
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ rng->set_seed(0);
+
+ INFO("Should give integer between 0 and 100.");
+ for (int i = 0; i < 1000; i++) {
+ uint32_t n = rng->randi() % 100;
+ CHECK(n >= 0);
+ CHECK(n <= 100);
+ }
+}
+
+TEST_CASE_MAY_FAIL("[RandomNumberGenerator] Integer 32 bit") {
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ rng->set_seed(0); // Change the seed if this fails.
+
+ bool higher = false;
+ int i;
+ for (i = 0; i < 1000; i++) {
+ uint32_t n = rng->randi();
+ if (n > 0x0fff'ffff) {
+ higher = true;
+ break;
+ }
+ }
+ INFO("Current seed: ", rng->get_seed());
+ INFO("Current iteration: ", i);
+ CHECK_MESSAGE(higher, "Given current seed, this should give an integer higher than 0x0fff'ffff at least once.");
+}
+
+TEST_CASE("[RandomNumberGenerator] Float and integer range") {
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ rng->set_seed(0);
+ uint64_t initial_state = rng->get_state();
+ uint32_t initial_seed = rng->get_seed();
+
+ INFO("Should give float between -100.0 and 100.0, base test.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n0 = rng->randf_range(-100.0, 100.0);
+ CHECK(n0 >= -100);
+ CHECK(n0 <= 100);
+ }
+
+ rng->randomize();
+ INFO("Should give float between -75.0 and 75.0.");
+ INFO("Shouldn't be affected by randomize.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n1 = rng->randf_range(-75.0, 75.0);
+ CHECK(n1 >= -75);
+ CHECK(n1 <= 75);
+ }
+
+ rng->set_state(initial_state);
+ INFO("Should give integer between -50 and 50.");
+ INFO("Shouldn't be affected by set_state.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n2 = rng->randi_range(-50, 50);
+ CHECK(n2 >= -50);
+ CHECK(n2 <= 50);
+ }
+
+ rng->set_seed(initial_seed);
+ INFO("Should give integer between -25 and 25.");
+ INFO("Shouldn't be affected by set_seed.");
+ for (int i = 0; i < 1000; i++) {
+ int32_t n3 = rng->randi_range(-25, 25);
+ CHECK(n3 >= -25);
+ CHECK(n3 <= 25);
+ }
+
+ rng->randf();
+ rng->randf();
+
+ INFO("Should give float between -10.0 and 10.0.");
+ INFO("Shouldn't be affected after generating new numbers.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n4 = rng->randf_range(-10.0, 10.0);
+ CHECK(n4 >= -10);
+ CHECK(n4 <= 10);
+ }
+
+ rng->randi();
+ rng->randi();
+
+ INFO("Should give integer between -5 and 5.");
+ INFO("Shouldn't be affected after generating new numbers.");
+ for (int i = 0; i < 1000; i++) {
+ real_t n5 = rng->randf_range(-5, 5);
+ CHECK(n5 >= -5);
+ CHECK(n5 <= 5);
+ }
+}
+
+TEST_CASE_MAY_FAIL("[RandomNumberGenerator] Normal distribution") {
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ rng->set_seed(1); // Change the seed if this fails.
+ INFO("Should give a number between -5 to 5 (5 std deviations away; above 99.7% chance it will be in this range).");
+ INFO("Standard randfn function call.");
+ for (int i = 0; i < 100; i++) {
+ real_t n = rng->randfn();
+ CHECK(n >= -5);
+ CHECK(n <= 5);
+ }
+
+ INFO("Should give number between -5 to 5 after multiple randi/randf calls.");
+ INFO("5 std deviations away; above 99.7% chance it will be in this range.");
+ rng->randf();
+ rng->randi();
+ for (int i = 0; i < 100; i++) {
+ real_t n = rng->randfn();
+ CHECK(n >= -5);
+ CHECK(n <= 5);
+ }
+
+ INFO("Checks if user defined mean and deviation work properly.");
+ INFO("5 std deviations away; above 99.7% chance it will be in this range.");
+ for (int i = 0; i < 100; i++) {
+ real_t n = rng->randfn(5, 10);
+ CHECK(n >= -45);
+ CHECK(n <= 55);
+ }
+
+ INFO("Checks if randfn works with changed seeds.");
+ INFO("5 std deviations away; above 99.7% chance it will be in this range.");
+ rng->randomize();
+ for (int i = 0; i < 100; i++) {
+ real_t n = rng->randfn(3, 3);
+ CHECK(n >= -12);
+ CHECK(n <= 18);
+ }
+}
+
TEST_CASE("[RandomNumberGenerator] Zero for first number immediately after seeding") {
Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
rng->set_seed(0);
uint32_t n1 = rng->randi();
uint32_t n2 = rng->randi();
- INFO("Initial random values: " << n1 << " " << n2);
+ INFO("Initial random values: ", n1, " ", n2);
CHECK(n1 != 0);
rng->set_seed(1);
uint32_t n3 = rng->randi();
uint32_t n4 = rng->randi();
- INFO("Values after changing the seed: " << n3 << " " << n4);
+ INFO("Values after changing the seed: ", n3, " ", n4);
CHECK(n3 != 0);
}
@@ -55,7 +199,7 @@ TEST_CASE("[RandomNumberGenerator] Restore state") {
Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
rng->randomize();
uint64_t last_seed = rng->get_seed();
- INFO("Current seed: " << last_seed);
+ INFO("Current seed: ", last_seed);
rng->randi();
rng->randi();
@@ -64,18 +208,18 @@ TEST_CASE("[RandomNumberGenerator] Restore state") {
"The seed should remain the same after generating some numbers");
uint64_t saved_state = rng->get_state();
- INFO("Current state: " << saved_state);
+ INFO("Current state: ", saved_state);
real_t f1_before = rng->randf();
real_t f2_before = rng->randf();
- INFO("This seed produces: " << f1_before << " " << f2_before);
+ INFO("This seed produces: ", f1_before, " ", f2_before);
// Restore now.
rng->set_state(saved_state);
real_t f1_after = rng->randf();
real_t f2_after = rng->randf();
- INFO("Resetting the state produces: " << f1_after << " " << f2_after);
+ INFO("Resetting the state produces: ", f1_after, " ", f2_after);
String msg = "Should restore the sequence of numbers after resetting the state";
CHECK_MESSAGE(f1_before == f1_after, msg);
@@ -85,27 +229,47 @@ TEST_CASE("[RandomNumberGenerator] Restore state") {
TEST_CASE("[RandomNumberGenerator] Restore from seed") {
Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
rng->set_seed(0);
- INFO("Current seed: " << rng->get_seed());
+ INFO("Current seed: ", rng->get_seed());
uint32_t s0_1_before = rng->randi();
uint32_t s0_2_before = rng->randi();
- INFO("This seed produces: " << s0_1_before << " " << s0_2_before);
+ INFO("This seed produces: ", s0_1_before, " ", s0_2_before);
rng->set_seed(9000);
- INFO("Current seed: " << rng->get_seed());
+ INFO("Current seed: ", rng->get_seed());
uint32_t s9000_1 = rng->randi();
uint32_t s9000_2 = rng->randi();
- INFO("This seed produces: " << s9000_1 << " " << s9000_2);
+ INFO("This seed produces: ", s9000_1, " ", s9000_2);
rng->set_seed(0);
- INFO("Current seed: " << rng->get_seed());
+ INFO("Current seed: ", rng->get_seed());
uint32_t s0_1_after = rng->randi();
uint32_t s0_2_after = rng->randi();
- INFO("This seed produces: " << s0_1_after << " " << s0_2_after);
+ INFO("This seed produces: ", s0_1_after, " ", s0_2_after);
String msg = "Should restore the sequence of numbers after resetting the seed";
CHECK_MESSAGE(s0_1_before == s0_1_after, msg);
CHECK_MESSAGE(s0_2_before == s0_2_after, msg);
}
+
+TEST_CASE_MAY_FAIL("[RandomNumberGenerator] randi_range bias check") {
+ int zeros = 0;
+ int ones = 0;
+ Ref<RandomNumberGenerator> rng = memnew(RandomNumberGenerator);
+ for (int i = 0; i < 10000; i++) {
+ int val = rng->randi_range(0, 1);
+ val == 0 ? zeros++ : ones++;
+ }
+ CHECK_MESSAGE(abs(zeros * 1.0 / ones - 1.0) < 0.1, "The ratio of zeros to ones should be nearly 1");
+
+ int vals[10] = { 0 };
+ for (int i = 0; i < 1000000; i++) {
+ vals[rng->randi_range(0, 9)]++;
+ }
+
+ for (int i = 0; i < 10; i++) {
+ CHECK_MESSAGE(abs(vals[i] / 1000000.0 - 0.1) < 0.01, "Each element should appear roughly 10% of the time");
+ }
+}
} // namespace TestRandomNumberGenerator
#endif // TEST_RANDOM_NUMBER_GENERATOR_H
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-07 19:41:24 +0000