Add unit tests for Curve2D

2 files changed, 229 insertions, 0 deletions

diff --git a/tests/scene/test_curve_2d.h b/tests/scene/test_curve_2d.h
new file mode 100644
index 0000000000..fc141f3d09
--- /dev/null
+++ b/tests/scene/test_curve_2d.h
@@ -0,0 +1,228 @@
+/**************************************************************************/
+/*  test_curve_2d.h                                                       */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifndef TEST_CURVE_2D_H
+#define TEST_CURVE_2D_H
+
+#include "core/math/math_funcs.h"
+#include "scene/resources/curve.h"
+
+#include "tests/test_macros.h"
+
+namespace TestCurve2D {
+
+void add_sample_curve_points(Ref<Curve2D> &curve) {
+	Vector2 p0 = Vector2(0, 0);
+	Vector2 p1 = Vector2(50, 0);
+	Vector2 p2 = Vector2(50, 50);
+	Vector2 p3 = Vector2(0, 50);
+
+	Vector2 control0 = p1 - p0;
+	Vector2 control1 = p3 - p2;
+
+	curve->add_point(p0, Vector2(), control0);
+	curve->add_point(p3, control1, Vector2());
+}
+
+TEST_CASE("[Curve2D] Default curve is empty") {
+	const Ref<Curve2D> curve = memnew(Curve2D);
+	CHECK(curve->get_point_count() == 0);
+}
+
+TEST_CASE("[Curve2D] Point management") {
+	Ref<Curve2D> curve = memnew(Curve2D);
+
+	SUBCASE("Functions for adding/removing points should behave as expected") {
+		curve->set_point_count(2);
+		CHECK(curve->get_point_count() == 2);
+
+		curve->remove_point(0);
+		CHECK(curve->get_point_count() == 1);
+
+		curve->add_point(Vector2());
+		CHECK(curve->get_point_count() == 2);
+
+		curve->clear_points();
+		CHECK(curve->get_point_count() == 0);
+	}
+
+	SUBCASE("Functions for changing single point properties should behave as expected") {
+		Vector2 new_in = Vector2(1, 1);
+		Vector2 new_out = Vector2(1, 1);
+		Vector2 new_pos = Vector2(1, 1);
+
+		curve->add_point(Vector2());
+
+		CHECK(curve->get_point_in(0) != new_in);
+		curve->set_point_in(0, new_in);
+		CHECK(curve->get_point_in(0) == new_in);
+
+		CHECK(curve->get_point_out(0) != new_out);
+		curve->set_point_out(0, new_out);
+		CHECK(curve->get_point_out(0) == new_out);
+
+		CHECK(curve->get_point_position(0) != new_pos);
+		curve->set_point_position(0, new_pos);
+		CHECK(curve->get_point_position(0) == new_pos);
+	}
+}
+
+TEST_CASE("[Curve2D] Baked") {
+	Ref<Curve2D> curve = memnew(Curve2D);
+
+	SUBCASE("Single Point") {
+		curve->add_point(Vector2());
+
+		CHECK(curve->get_baked_length() == 0);
+		CHECK(curve->get_baked_points().size() == 1);
+	}
+
+	SUBCASE("Straight line") {
+		curve->add_point(Vector2());
+		curve->add_point(Vector2(0, 50));
+
+		CHECK(Math::is_equal_approx(curve->get_baked_length(), 50));
+		CHECK(curve->get_baked_points().size() == 15);
+	}
+
+	SUBCASE("Beziér Curve") {
+		add_sample_curve_points(curve);
+
+		real_t len = curve->get_baked_length();
+		real_t n_points = curve->get_baked_points().size();
+		// Curve length should be bigger than a straight between points
+		CHECK(len > 50);
+
+		SUBCASE("Increase bake interval") {
+			curve->set_bake_interval(10.0);
+			// Lower resolution should imply less points and smaller length
+			CHECK(curve->get_baked_length() < len);
+			CHECK(curve->get_baked_points().size() < n_points);
+		}
+	}
+}
+
+TEST_CASE("[Curve2D] Sampling") {
+	// Sampling over a simple straight line to make assertions simpler
+	Ref<Curve2D> curve = memnew(Curve2D);
+	curve->add_point(Vector2());
+	curve->add_point(Vector2(0, 50));
+
+	SUBCASE("sample") {
+		CHECK(curve->sample(0, 0) == Vector2(0, 0));
+		CHECK(curve->sample(0, 0.5) == Vector2(0, 25));
+		CHECK(curve->sample(0, 1) == Vector2(0, 50));
+	}
+
+	SUBCASE("samplef") {
+		CHECK(curve->samplef(0) == Vector2(0, 0));
+		CHECK(curve->samplef(0.5) == Vector2(0, 25));
+		CHECK(curve->samplef(1) == Vector2(0, 50));
+	}
+
+	SUBCASE("sample_baked") {
+		CHECK(curve->sample_baked(curve->get_closest_offset(Vector2(0, 0))) == Vector2(0, 0));
+		CHECK(curve->sample_baked(curve->get_closest_offset(Vector2(0, 25))) == Vector2(0, 25));
+		CHECK(curve->sample_baked(curve->get_closest_offset(Vector2(0, 50))) == Vector2(0, 50));
+	}
+
+	SUBCASE("sample_baked_with_rotation") {
+		const real_t pi = 3.14159;
+		Transform2D t = curve->sample_baked_with_rotation(curve->get_closest_offset(Vector2(0, 0)));
+		CHECK(t.get_origin() == Vector2(0, 0));
+		CHECK(Math::is_equal_approx(t.get_rotation(), pi));
+
+		t = curve->sample_baked_with_rotation(curve->get_closest_offset(Vector2(0, 25)));
+		CHECK(t.get_origin() == Vector2(0, 25));
+		CHECK(Math::is_equal_approx(t.get_rotation(), pi));
+
+		t = curve->sample_baked_with_rotation(curve->get_closest_offset(Vector2(0, 50)));
+		CHECK(t.get_origin() == Vector2(0, 50));
+		CHECK(Math::is_equal_approx(t.get_rotation(), pi));
+	}
+
+	SUBCASE("get_closest_point") {
+		CHECK(curve->get_closest_point(Vector2(0, 0)) == Vector2(0, 0));
+		CHECK(curve->get_closest_point(Vector2(0, 25)) == Vector2(0, 25));
+		CHECK(curve->get_closest_point(Vector2(50, 25)) == Vector2(0, 25));
+		CHECK(curve->get_closest_point(Vector2(0, 50)) == Vector2(0, 50));
+		CHECK(curve->get_closest_point(Vector2(50, 50)) == Vector2(0, 50));
+		CHECK(curve->get_closest_point(Vector2(0, 100)) == Vector2(0, 50));
+	}
+}
+
+TEST_CASE("[Curve2D] Tessellation") {
+	Ref<Curve2D> curve = memnew(Curve2D);
+	add_sample_curve_points(curve);
+
+	const int default_size = curve->tessellate().size();
+
+	SUBCASE("Increase to max stages should increase num of points") {
+		CHECK(curve->tessellate(6).size() > default_size);
+	}
+
+	SUBCASE("Decrease to max stages should decrease num of points") {
+		CHECK(curve->tessellate(4).size() < default_size);
+	}
+
+	SUBCASE("Increase to tolerance should decrease num of points") {
+		CHECK(curve->tessellate(5, 5).size() < default_size);
+	}
+
+	SUBCASE("Decrease to tolerance should increase num of points") {
+		CHECK(curve->tessellate(5, 3).size() > default_size);
+	}
+
+	SUBCASE("Adding a straight segment should only add the last point to tessellate return array") {
+		curve->add_point(Vector2(0, 100));
+		PackedVector2Array tes = curve->tessellate();
+		CHECK(tes.size() == default_size + 1);
+		CHECK(tes[tes.size() - 1] == Vector2(0, 100));
+		CHECK(tes[tes.size() - 2] == Vector2(0, 50));
+	}
+}
+
+TEST_CASE("[Curve2D] Even length tessellation") {
+	Ref<Curve2D> curve = memnew(Curve2D);
+	add_sample_curve_points(curve);
+
+	const int default_size = curve->tessellate_even_length().size();
+
+	// Default tessellate_even_length tolerance_length is 20.0, by adding a 100 units
+	// straight, we expect the total size to be increased by more than 5,
+	// that is, the algo will pick a length < 20.0 and will divide the straight as
+	// well as the curve as opposed to tessellate() which only adds the final point
+	curve->add_point(Vector2(0, 150));
+	CHECK(curve->tessellate_even_length().size() > default_size + 5);
+}
+
+} // namespace TestCurve2D
+
+#endif // TEST_CURVE_2D_H
diff --git a/tests/test_main.cpp b/tests/test_main.cpp
index 85a271fc9c..8c563f94ac 100644
--- a/tests/test_main.cpp
+++ b/tests/test_main.cpp
@@ -91,6 +91,7 @@
 #include "tests/scene/test_bit_map.h"
 #include "tests/scene/test_code_edit.h"
 #include "tests/scene/test_curve.h"
+#include "tests/scene/test_curve_2d.h"
 #include "tests/scene/test_gradient.h"
 #include "tests/scene/test_node.h"
 #include "tests/scene/test_path_2d.h"