Class reference
Transform2D
A 2×3 matrix representing a 2D transformation.
Description
The Transform2D built-in Variant type is a 2×3 matrix representing a transformation in 2D space. It contains three Vector2 values: x, y, and origin. Together, they can represent translation, rotation, scale, and skew. The x and y axes form a 2×2 matrix, known as the transform's basis. The length of each axis (Vector2.length()) influences the transform's scale, while the direction of all axes influence the rotation. Usually, both axes are perpendicular to one another. However, when you rotate one axis individually, the transform becomes skewed. Applying a skewed transform to a 2D sprite will make the sprite appear distorted. For a general introduction, see the Matrices and transforms tutorial. Note: Unlike Transform3D, there is no 2D equivalent to the Basis type. All mentions of "basis" refer to the x and y components of Transform2D.
Properties
Vector2 origin = Vector2(0, 0)
Vector2 origin = Vector2(0, 0)The translation offset of this transform, and the column 2 of the matrix. In 2D space, this can be seen as the position.
Vector2 x = Vector2(1, 0)
Vector2 x = Vector2(1, 0)The transform basis's X axis, and the column 0 of the matrix. Combined with y, this represents the transform's rotation, scale, and skew. On the identity transform, this vector points right (Vector2.RIGHT).
Vector2 y = Vector2(0, 1)
Vector2 y = Vector2(0, 1)The transform basis's Y axis, and the column 1 of the matrix. Combined with x, this represents the transform's rotation, scale, and skew. On the identity transform, this vector points down (Vector2.DOWN).
Constructors
Transform2D Transform2D()
Transform2D Transform2D()Constructs a Transform2D identical to IDENTITY. Note: In C#, this constructs a Transform2D with all of its components set to Vector2.ZERO.
Transform2D Transform2D(Transform2D from)
Transform2D Transform2D(Transform2D from)Constructs a Transform2D as a copy of the given Transform2D.
Transform2D Transform2D(float rotation, Vector2 position)
Transform2D Transform2D(float rotation, Vector2 position)Constructs a Transform2D from a given angle (in radians) and position.
Transform2D Transform2D(float rotation, Vector2 scale, float skew, Vector2 position)
Transform2D Transform2D(float rotation, Vector2 scale, float skew, Vector2 position)Constructs a Transform2D from a given angle (in radians), scale, skew (in radians), and position.
Transform2D Transform2D(Vector2 x_axis, Vector2 y_axis, Vector2 origin)
Transform2D Transform2D(Vector2 x_axis, Vector2 y_axis, Vector2 origin)Constructs a Transform2D from 3 Vector2 values representing x, y, and the origin (the three matrix columns).
Methods
Transform2D affine_inverse() const
Transform2D affine_inverse() constReturns the inverted version of this transform. Unlike inverse(), this method works with almost any basis, including non-uniform ones, but is slower. Note: For this method to return correctly, the transform's basis needs to have a determinant that is not exactly 0.0 (see determinant()).
Vector2 basis_xform(Vector2 v) const
Vector2 basis_xform(Vector2 v) constReturns a copy of the v vector, transformed (multiplied) by the transform basis's matrix. Unlike the multiplication operator (*), this method ignores the origin.
Vector2 basis_xform_inv(Vector2 v) const
Vector2 basis_xform_inv(Vector2 v) constReturns a copy of the v vector, transformed (multiplied) by the inverse transform basis's matrix (see inverse()). This method ignores the origin. Note: This method assumes that this transform's basis is orthonormal (see orthonormalized()). If the basis is not orthonormal, transform.affine_inverse().basis_xform(vector) should be used instead (see affine_inverse()).
float determinant() const
float determinant() constReturns the determinant of this transform basis's matrix. For advanced math, this number can be used to determine a few attributes: - If the determinant is exactly 0.0, the basis is not invertible (see inverse()). - If the determinant is a negative number, the basis represents a negative scale. Note: If the basis's scale is the same for every axis, its determinant is always that scale by the power of 2.
Vector2 get_origin() const
Vector2 get_origin() constReturns this transform's translation. Equivalent to origin.
float get_rotation() const
float get_rotation() constReturns this transform's rotation (in radians). This is equivalent to x's angle (see Vector2.angle()).
Vector2 get_scale() const
Vector2 get_scale() constReturns the length of both x and y, as a Vector2. If this transform's basis is not skewed, this value is the scaling factor. It is not affected by rotation.
var my_transform = Transform2D(
Vector2(2, 0),
Vector2(0, 4),
Vector2(0, 0)
)
# Rotating the Transform2D in any way preserves its scale.
my_transform = my_transform.rotated(TAU / 2)
print(my_transform.get_scale()) # Prints (2.0, 4.0)
var myTransform = new Transform2D(
Vector3(2.0f, 0.0f),
Vector3(0.0f, 4.0f),
Vector3(0.0f, 0.0f)
);
// Rotating the Transform2D in any way preserves its scale.
myTransform = myTransform.Rotated(Mathf.Tau / 2.0f);
GD.Print(myTransform.GetScale()); // Prints (2, 4)
Note: If the value returned by determinant() is negative, the scale is also negative.
float get_skew() const
float get_skew() constReturns this transform's skew (in radians).
Transform2D interpolate_with(Transform2D xform, float weight) const
Transform2D interpolate_with(Transform2D xform, float weight) constReturns the result of the linear interpolation between this transform and xform by the given weight. The weight should be between 0.0 and 1.0 (inclusive). Values outside this range are allowed and can be used to perform extrapolation instead.
Transform2D inverse() const
Transform2D inverse() constReturns the inverted version of this transform. Note: For this method to return correctly, the transform's basis needs to be orthonormal (see orthonormalized()). That means the basis should only represent a rotation. If it does not, use affine_inverse() instead.
bool is_conformal() const
bool is_conformal() constReturns true if this transform's basis is conformal. A conformal basis is both orthogonal (the axes are perpendicular to each other) and uniform (the axes share the same length). This method can be especially useful during physics calculations.
bool is_equal_approx(Transform2D xform) const
bool is_equal_approx(Transform2D xform) constReturns true if this transform and xform are approximately equal, by running @GlobalScope.is_equal_approx() on each component.
bool is_finite() const
bool is_finite() constReturns true if this transform is finite, by calling @GlobalScope.is_finite() on each component.
Transform2D looking_at(Vector2 target = Vector2(0, 0)) const
Transform2D looking_at(Vector2 target = Vector2(0, 0)) constReturns a copy of the transform rotated such that the rotated X-axis points towards the target position, in global space.
Transform2D orthonormalized() const
Transform2D orthonormalized() constReturns a copy of this transform with its basis orthonormalized. An orthonormal basis is both orthogonal (the axes are perpendicular to each other) and normalized (the axes have a length of 1.0), which also means it can only represent a rotation.
Transform2D rotated(float angle) const
Transform2D rotated(float angle) constReturns a copy of this transform rotated by the given angle (in radians). If angle is positive, the transform is rotated clockwise. This method is an optimized version of multiplying the given transform X with a corresponding rotation transform R from the left, i.e., R * X. This can be seen as transforming with respect to the global/parent frame.
Transform2D rotated_local(float angle) const
Transform2D rotated_local(float angle) constReturns a copy of the transform rotated by the given angle (in radians). This method is an optimized version of multiplying the given transform X with a corresponding rotation transform R from the right, i.e., X * R. This can be seen as transforming with respect to the local frame.
Transform2D scaled(Vector2 scale) const
Transform2D scaled(Vector2 scale) constReturns a copy of the transform scaled by the given scale factor. This method is an optimized version of multiplying the given transform X with a corresponding scaling transform S from the left, i.e., S * X. This can be seen as transforming with respect to the global/parent frame.
Transform2D scaled_local(Vector2 scale) const
Transform2D scaled_local(Vector2 scale) constReturns a copy of the transform scaled by the given scale factor. This method is an optimized version of multiplying the given transform X with a corresponding scaling transform S from the right, i.e., X * S. This can be seen as transforming with respect to the local frame.
Transform2D translated(Vector2 offset) const
Transform2D translated(Vector2 offset) constReturns a copy of the transform translated by the given offset. This method is an optimized version of multiplying the given transform X with a corresponding translation transform T from the left, i.e., T * X. This can be seen as transforming with respect to the global/parent frame.
Transform2D translated_local(Vector2 offset) const
Transform2D translated_local(Vector2 offset) constReturns a copy of the transform translated by the given offset. This method is an optimized version of multiplying the given transform X with a corresponding translation transform T from the right, i.e., X * T. This can be seen as transforming with respect to the local frame.
Constants
IDENTITY = Transform2D(1, 0, 0, 1, 0, 0)
The identity Transform2D. This is a transform with no translation, no rotation, and a scale of Vector2.ONE. This also means that: - The x points right (Vector2.RIGHT); - The y points down (Vector2.DOWN).
var transform = Transform2D.IDENTITY
print("| X | Y | Origin")
print("| %.f | %.f | %.f" % [transform.x.x, transform.y.x, transform.origin.x])
print("| %.f | %.f | %.f" % [transform.x.y, transform.y.y, transform.origin.y])
# Prints:
# | X | Y | Origin
# | 1 | 0 | 0
# | 0 | 1 | 0
If a Vector2, a Rect2, a PackedVector2Array, or another Transform2D is transformed (multiplied) by this constant, no transformation occurs. Note: In GDScript, this constant is equivalent to creating a Transform2D without any arguments. It can be used to make your code clearer, and for consistency with C#.
FLIP_X = Transform2D(-1, 0, 0, 1, 0, 0)
When any transform is multiplied by FLIP_X, it negates all components of the x axis (the X column). When FLIP_X is multiplied by any transform, it negates the Vector2.x component of all axes (the X row).
FLIP_Y = Transform2D(1, 0, 0, -1, 0, 0)
When any transform is multiplied by FLIP_Y, it negates all components of the y axis (the Y column). When FLIP_Y is multiplied by any transform, it negates the Vector2.y component of all axes (the Y row).
Operators
bool operator !=(Transform2D right)
bool operator !=(Transform2D right)Returns true if the components of both transforms are not equal. Note: Due to floating-point precision errors, consider using is_equal_approx() instead, which is more reliable.
PackedVector2Array operator *(PackedVector2Array right)
PackedVector2Array operator *(PackedVector2Array right)Transforms (multiplies) every Vector2 element of the given PackedVector2Array by this transformation matrix. On larger arrays, this operation is much faster than transforming each Vector2 individually.
Rect2 operator *(Rect2 right)
Rect2 operator *(Rect2 right)Transforms (multiplies) the Rect2 by this transformation matrix.
Transform2D operator *(Transform2D right)
Transform2D operator *(Transform2D right)Transforms (multiplies) this transform by the right transform. This is the operation performed between parent and child CanvasItem nodes. Note: If you need to only modify one attribute of this transform, consider using one of the following methods, instead: - For translation, see translated() or translated_local(). - For rotation, see rotated() or rotated_local(). - For scale, see scaled() or scaled_local().
Vector2 operator *(Vector2 right)
Vector2 operator *(Vector2 right)Transforms (multiplies) the Vector2 by this transformation matrix.
Transform2D operator *(float right)
Transform2D operator *(float right)Multiplies all components of the Transform2D by the given float, including the origin. This affects the transform's scale uniformly.
Transform2D operator *(int right)
Transform2D operator *(int right)Multiplies all components of the Transform2D by the given int, including the origin. This affects the transform's scale uniformly.
Transform2D operator /(float right)
Transform2D operator /(float right)Divides all components of the Transform2D by the given float, including the origin. This affects the transform's scale uniformly.
Transform2D operator /(int right)
Transform2D operator /(int right)Divides all components of the Transform2D by the given int, including the origin. This affects the transform's scale uniformly.
bool operator ==(Transform2D right)
bool operator ==(Transform2D right)Returns true if the components of both transforms are exactly equal. Note: Due to floating-point precision errors, consider using is_equal_approx() instead, which is more reliable.
Vector2 operator [](int index)
Vector2 operator [](int index)Accesses each axis (column) of this transform by their index. Index 0 is the same as x, index 1 is the same as y, and index 2 is the same as origin.