diff --git a/source/blender/blenlib/BLI_float3x3.hh b/source/blender/blenlib/BLI_float3x3.hh new file mode 100644 index 00000000000..62478556d9b --- /dev/null +++ b/source/blender/blenlib/BLI_float3x3.hh @@ -0,0 +1,192 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#pragma once + +#include +#include + +#include "BLI_assert.h" +#include "BLI_math_base.h" +#include "BLI_math_matrix.h" +#include "BLI_math_vec_types.hh" +#include "BLI_math_vector.h" + +namespace blender { + +struct float3x3 { + /* A 3x3 matrix in column major order. */ + float values[3][3]; + + float3x3() = default; + + float3x3(const float *matrix) + { + memcpy(values, matrix, sizeof(float) * 3 * 3); + } + + float3x3(const float matrix[3][3]) : float3x3(static_cast(matrix[0])) + { + } + + static float3x3 zero() + { + float3x3 result; + zero_m3(result.values); + return result; + } + + static float3x3 identity() + { + float3x3 result; + unit_m3(result.values); + return result; + } + + static float3x3 from_translation(const float2 translation) + { + float3x3 result = identity(); + result.values[2][0] = translation.x; + result.values[2][1] = translation.y; + return result; + } + + static float3x3 from_rotation(float rotation) + { + float3x3 result = zero(); + const float cosine = std::cos(rotation); + const float sine = std::sin(rotation); + result.values[0][0] = cosine; + result.values[0][1] = sine; + result.values[1][0] = -sine; + result.values[1][1] = cosine; + result.values[2][2] = 1.0f; + return result; + } + + static float3x3 from_translation_rotation_scale(const float2 translation, + float rotation, + const float2 scale) + { + float3x3 result; + const float cosine = std::cos(rotation); + const float sine = std::sin(rotation); + result.values[0][0] = scale.x * cosine; + result.values[0][1] = scale.x * sine; + result.values[0][2] = 0.0f; + result.values[1][0] = scale.y * -sine; + result.values[1][1] = scale.y * cosine; + result.values[1][2] = 0.0f; + result.values[2][0] = translation.x; + result.values[2][1] = translation.y; + result.values[2][2] = 1.0f; + return result; + } + + static float3x3 from_normalized_axes(const float2 translation, + const float2 horizontal, + const float2 vertical) + { + BLI_ASSERT_UNIT_V2(horizontal); + BLI_ASSERT_UNIT_V2(vertical); + + float3x3 result; + result.values[0][0] = horizontal.x; + result.values[0][1] = horizontal.y; + result.values[0][2] = 0.0f; + result.values[1][0] = vertical.x; + result.values[1][1] = vertical.y; + result.values[1][2] = 0.0f; + result.values[2][0] = translation.x; + result.values[2][1] = translation.y; + result.values[2][2] = 1.0f; + return result; + } + + /* Construct a transformation that is pivoted around the given origin point. So for instance, + * from_origin_transformation(from_rotation(M_PI_2), float2(0.0f, 2.0f)) + * will construct a transformation representing a 90 degree rotation around the point (0, 2). */ + static float3x3 from_origin_transformation(const float3x3 &transformation, const float2 origin) + { + return from_translation(origin) * transformation * from_translation(-origin); + } + + operator float *() + { + return &values[0][0]; + } + + operator const float *() const + { + return &values[0][0]; + } + + float *operator[](const int64_t index) + { + BLI_assert(index >= 0); + BLI_assert(index < 3); + return &values[index][0]; + } + + const float *operator[](const int64_t index) const + { + BLI_assert(index >= 0); + BLI_assert(index < 3); + return &values[index][0]; + } + + using c_style_float3x3 = float[3][3]; + c_style_float3x3 &ptr() + { + return values; + } + + const c_style_float3x3 &ptr() const + { + return values; + } + + friend float3x3 operator*(const float3x3 &a, const float3x3 &b) + { + float3x3 result; + mul_m3_m3m3(result.values, a.values, b.values); + return result; + } + + void operator*=(const float3x3 &other) + { + mul_m3_m3_post(values, other.values); + } + + friend float2 operator*(const float3x3 &transformation, const float2 &vector) + { + float2 result; + mul_v2_m3v2(result, transformation.values, vector); + return result; + } + + friend float2 operator*(const float3x3 &transformation, const float (*vector)[2]) + { + return transformation * float2(vector); + } + + float3x3 transposed() const + { + float3x3 result; + transpose_m3_m3(result.values, values); + return result; + } + + float3x3 inverted() const + { + float3x3 result; + invert_m3_m3(result.values, values); + return result; + } + + friend bool operator==(const float3x3 &a, const float3x3 &b) + { + return equals_m3m3(a.values, b.values); + } +}; + +} // namespace blender diff --git a/source/blender/blenlib/CMakeLists.txt b/source/blender/blenlib/CMakeLists.txt index 4e76ae3e855..109230ebfa7 100644 --- a/source/blender/blenlib/CMakeLists.txt +++ b/source/blender/blenlib/CMakeLists.txt @@ -199,6 +199,7 @@ set(SRC BLI_fileops.hh BLI_fileops_types.h BLI_filereader.h + BLI_float3x3.hh BLI_float4x4.hh BLI_fnmatch.h BLI_function_ref.hh @@ -431,6 +432,7 @@ if(WITH_GTESTS) tests/BLI_edgehash_test.cc tests/BLI_expr_pylike_eval_test.cc tests/BLI_fileops_test.cc + tests/BLI_float3x3_test.cc tests/BLI_function_ref_test.cc tests/BLI_generic_array_test.cc tests/BLI_generic_span_test.cc diff --git a/source/blender/blenlib/tests/BLI_float3x3_test.cc b/source/blender/blenlib/tests/BLI_float3x3_test.cc new file mode 100644 index 00000000000..d22993ee69e --- /dev/null +++ b/source/blender/blenlib/tests/BLI_float3x3_test.cc @@ -0,0 +1,119 @@ +/* SPDX-License-Identifier: Apache-2.0 */ + +#include "testing/testing.h" + +#include "BLI_float3x3.hh" +#include "BLI_math_base.h" +#include "BLI_math_vec_types.hh" + +namespace blender::tests { + +TEST(float3x3, Identity) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::identity(); + float2 result = transformation * point; + EXPECT_EQ(result, point); +} + +TEST(float3x3, Translation) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::from_translation(float2(5.0f, 3.0f)); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], 6.0f); + EXPECT_FLOAT_EQ(result[1], 5.0f); +} + +TEST(float3x3, Rotation) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::from_rotation(M_PI_2); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], -2.0f); + EXPECT_FLOAT_EQ(result[1], 1.0f); +} + +TEST(float3x3, TranslationRotationScale) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::from_translation_rotation_scale( + float2(1.0f, 3.0f), M_PI_2, float2(2.0f, 3.0f)); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], -5.0f); + EXPECT_FLOAT_EQ(result[1], 5.0f); +} + +TEST(float3x3, NormalizedAxes) +{ + float2 point(1.0f, 2.0f); + + /* The horizontal is aligned with (1, 1) and vertical is aligned with (-1, 1), in other words, a + * Pi / 4 rotation. */ + float value = std::sqrt(2.0f) / 2.0f; + float3x3 transformation = float3x3::from_normalized_axes( + float2(1.0f, 3.0f), float2(value), float2(-value, value)); + float2 result = transformation * point; + + float3x3 expected_transformation = float3x3::from_translation_rotation_scale( + float2(1.0f, 3.0f), M_PI_4, float2(1.0f)); + float2 expected = expected_transformation * point; + + EXPECT_FLOAT_EQ(result[0], expected[0]); + EXPECT_FLOAT_EQ(result[1], expected[1]); +} + +TEST(float3x3, PostTransformationMultiplication) +{ + float2 point(1.0f, 2.0f); + float3x3 translation = float3x3::from_translation(float2(5.0f, 3.0f)); + float3x3 rotation = float3x3::from_rotation(M_PI_2); + float3x3 transformation = translation * rotation; + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], 3.0f); + EXPECT_FLOAT_EQ(result[1], 4.0f); +} + +TEST(float3x3, PreTransformationMultiplication) +{ + float2 point(1.0f, 2.0f); + float3x3 translation = float3x3::from_translation(float2(5.0f, 3.0f)); + float3x3 rotation = float3x3::from_rotation(M_PI_2); + float3x3 transformation = rotation * translation; + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], -5.0f); + EXPECT_FLOAT_EQ(result[1], 6.0f); +} + +TEST(float3x3, TransformationMultiplicationAssignment) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::from_translation(float2(5.0f, 3.0f)); + transformation *= float3x3::from_rotation(M_PI_2); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], 3.0f); + EXPECT_FLOAT_EQ(result[1], 4.0f); +} + +TEST(float3x3, Inverted) +{ + float2 point(1.0f, 2.0f); + float3x3 transformation = float3x3::from_translation_rotation_scale( + float2(1.0f, 3.0f), M_PI_4, float2(1.0f)); + transformation *= transformation.inverted(); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], 1.0f); + EXPECT_FLOAT_EQ(result[1], 2.0f); +} + +TEST(float3x3, Origin) +{ + float2 point(1.0f, 2.0f); + float3x3 rotation = float3x3::from_rotation(M_PI_2); + float3x3 transformation = float3x3::from_origin_transformation(rotation, float2(0.0f, 2.0f)); + float2 result = transformation * point; + EXPECT_FLOAT_EQ(result[0], 0.0f); + EXPECT_FLOAT_EQ(result[1], 3.0f); +} + +} // namespace blender::tests