Struct components::platform::core::Matrix

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pub struct Matrix {Show 16 fields
    pub xx: f32,
    pub yx: f32,
    pub zx: f32,
    pub wx: f32,
    pub xy: f32,
    pub yy: f32,
    pub zy: f32,
    pub wy: f32,
    pub xz: f32,
    pub yz: f32,
    pub zz: f32,
    pub wz: f32,
    pub xw: f32,
    pub yw: f32,
    pub zw: f32,
    pub ww: f32,
}

Fields

xx: f32yx: f32zx: f32wx: f32xy: f32yy: f32zy: f32wy: f32xz: f32yz: f32zz: f32wz: f32xw: f32yw: f32zw: f32ww: f32

Implementations

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impl Matrix

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pub fn frustum(
    &mut self,
    left: f32,
    right: f32,
    bottom: f32,
    top: f32,
    z_near: f32,
    z_far: f32
)

Multiplies self by the given frustum perspective matrix.

`left`

X position of the left clipping plane where it intersects the near clipping plane

`right`

X position of the right clipping plane where it intersects the near clipping plane

`bottom`

Y position of the bottom clipping plane where it intersects the near clipping plane

`top`

Y position of the top clipping plane where it intersects the near clipping plane

`z_near`

The distance to the near clipping plane (Must be positive)

`z_far`

The distance to the far clipping plane (Must be positive)

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pub fn inverse(&self) -> (bool, Matrix )

Gets the inverse transform of a given matrix and uses it to initialize a new Matrix.

Although the first parameter is annotated as const to indicate that the transform it represents isn’t modified this fn may technically save a copy of the inverse transform within the given Matrix so that subsequent requests for the inverse transform may avoid costly inversion calculations.

`inverse`

The destination for a 4x4 inverse transformation matrix

Returns

true if the inverse was successfully calculated or false for degenerate transformations that can’t be inverted (in this case the inverse matrix will simply be initialized with the identity matrix)

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pub fn init_from_array(&mut self, array: &[f32 ])

Initializes self with the contents of array

`array`

A linear array of 16 floats (column-major order)

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pub fn init_from_euler(&mut self, euler: &Euler)

Initializes self from a Euler rotation.

`euler`

A Euler

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pub fn init_from_quaternion(&mut self, quaternion: &Quaternion)

Initializes self from a Quaternion rotation.

`quaternion`

A Quaternion

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pub fn init_identity(&mut self)

Resets matrix to the identity matrix:

  .xx=1; .xy=0; .xz=0; .xw=0;
  .yx=0; .yy=1; .yz=0; .yw=0;
  .zx=0; .zy=0; .zz=1; .zw=0;
  .wx=0; .wy=0; .wz=0; .ww=1;

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pub fn init_translation(&mut self, tx: f32, ty: f32, tz: f32)

Resets matrix to the (tx, ty, tz) translation matrix:

  .xx=1; .xy=0; .xz=0; .xw=tx;
  .yx=0; .yy=1; .yz=0; .yw=ty;
  .zx=0; .zy=0; .zz=1; .zw=tz;
  .wx=0; .wy=0; .wz=0; .ww=1;

`tx`

x coordinate of the translation vector

`ty`

y coordinate of the translation vector

`tz`

z coordinate of the translation vector

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pub fn is_identity(&self) -> bool

Determines if the given matrix is an identity matrix.

Returns

true if self is an identity matrix else false

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pub fn look_at(
    &mut self,
    eye_position_x: f32,
    eye_position_y: f32,
    eye_position_z: f32,
    object_x: f32,
    object_y: f32,
    object_z: f32,
    world_up_x: f32,
    world_up_y: f32,
    world_up_z: f32
)

Applies a view transform self that positions the camera at the coordinate (eye_position_x, eye_position_y, eye_position_z) looking towards an object at the coordinate (object_x, object_y, object_z). The top of the camera is aligned to the given world up vector, which is normally simply (0, 1, 0) to map up to the positive direction of the y axis.

Because there is a lot of missleading documentation online for gluLookAt regarding the up vector we want to try and be a bit clearer here.

The up vector should simply be relative to your world coordinates and does not need to change as you move the eye and object positions. Many online sources may claim that the up vector needs to be perpendicular to the vector between the eye and object position (partly because the man page is somewhat missleading) but that is not necessary for this function.

You should never look directly along the world-up vector.

It is assumed you are using a typical projection matrix where your origin maps to the center of your viewport.

Almost always when you use this fn it should be the first transform applied to a new modelview transform

`eye_position_x`

The X coordinate to look from

`eye_position_y`

The Y coordinate to look from

`eye_position_z`

The Z coordinate to look from

`object_x`

The X coordinate of the object to look at

`object_y`

The Y coordinate of the object to look at

`object_z`

The Z coordinate of the object to look at

`world_up_x`

The X component of the world’s up direction vector

`world_up_y`

The Y component of the world’s up direction vector

`world_up_z`

The Z component of the world’s up direction vector

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pub fn multiply(&mut self, a: &Matrix, b: &Matrix)

Multiplies the two supplied matrices together and stores the resulting matrix inside self.

It is possible to multiply the a matrix in-place, so self can be equal to a but can’t be equal to b.

`a`

A 4x4 transformation matrix

`b`

A 4x4 transformation matrix

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pub fn orthographic(
    &mut self,
    x_1: f32,
    y_1: f32,
    x_2: f32,
    y_2: f32,
    near: f32,
    far: f32
)

Multiplies self by a parallel projection matrix.

`x_1`

The x coordinate for the first vertical clipping plane

`y_1`

The y coordinate for the first horizontal clipping plane

`x_2`

The x coordinate for the second vertical clipping plane

`y_2`

The y coordinate for the second horizontal clipping plane

`near`

The distance to the near clipping plane (will be negative if the plane is behind the viewer)

`far`

The distance to the far clipping plane (will be negative if the plane is behind the viewer)

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pub fn perspective(&mut self, fov_y: f32, aspect: f32, z_near: f32, z_far: f32)

Multiplies self by the described perspective matrix

You should be careful not to have to great a z_far / z_near ratio since that will reduce the effectiveness of depth testing since there wont be enough precision to identify the depth of objects near to each other.

`fov_y`

Vertical field of view angle in degrees.

`aspect`

The (width over height) aspect ratio for display

`z_near`

The distance to the near clipping plane (Must be positive, and must not be 0)

`z_far`

The distance to the far clipping plane (Must be positive)

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pub fn project_points(
    &self,
    n_components: i32,
    stride_in: usize,
    points_in: &[u8 ],
    stride_out: usize,
    points_out: &[u8 ],
    n_points: i32
)

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pub fn rotate(&mut self, angle: f32, x: f32, y: f32, z: f32)

Multiplies self with a rotation matrix that applies a rotation of angle degrees around the specified 3D vector.

`angle`

The angle you want to rotate in degrees

`x`

X component of your rotation vector

`y`

Y component of your rotation vector

`z`

Z component of your rotation vector

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pub fn rotate_euler(&mut self, euler: &Euler)

Multiplies self with a rotation transformation described by the given Euler.

`euler`

A euler describing a rotation

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pub fn rotate_quaternion(&mut self, quaternion: &Quaternion)

Multiplies self with a rotation transformation described by the given Quaternion.

`quaternion`

A quaternion describing a rotation

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pub fn scale(&mut self, sx: f32, sy: f32, sz: f32)

Multiplies self with a transform matrix that scales along the X, Y and Z axis.

`sx`

The X scale factor

`sy`

The Y scale factor

`sz`

The Z scale factor

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pub fn transform_point(
    &self,
    x: &mut f32,
    y: &mut f32,
    z: &mut f32,
    w: &mut f32
)

Transforms a point whos position is given and returned as four float components.

`x`

The X component of your points position

`y`

The Y component of your points position

`z`

The Z component of your points position

`w`

The W component of your points position

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pub fn transform_points(
    &self,
    n_components: i32,
    stride_in: usize,
    points_in: &[u8 ],
    stride_out: usize,
    points_out: &[u8 ],
    n_points: i32
)

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pub fn translate(&mut self, x: f32, y: f32, z: f32)

Multiplies self with a transform matrix that translates along the X, Y and Z axis.

`x`

The X translation you want to apply

`y`

The Y translation you want to apply

`z`

The Z translation you want to apply

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pub fn transpose(&mut self)

Replaces self with its transpose. Ie, every element (i,j) in the new matrix is taken from element (j,i) in the old matrix.

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pub fn view_2d_in_frustum(
    &mut self,
    left: f32,
    right: f32,
    bottom: f32,
    top: f32,
    z_near: f32,
    z_2d: f32,
    width_2d: f32,
    height_2d: f32
)

Multiplies self by a view transform that maps the 2D coordinates (0,0) top left and (width_2d,height_2d) bottom right the full viewport size. Geometry at a depth of 0 will now lie on this 2D plane.

Note: this doesn’t multiply the matrix by any projection matrix, but it assumes you have a perspective projection as defined by passing the corresponding arguments to Matrix::frustum.

Toolkits such as Clutter that mix 2D and 3D drawing can use this to create a 2D coordinate system within a 3D perspective projected view frustum.

`left`

coord of left vertical clipping plane

`right`

coord of right vertical clipping plane

`bottom`

coord of bottom horizontal clipping plane

`top`

coord of top horizontal clipping plane

`z_near`

The distance to the near clip plane. Never pass 0 and always pass a positive number.

`z_2d`

The distance to the 2D plane. (Should always be positive and be between z_near and the z_far value that was passed to Matrix::frustum)

`width_2d`

The width of the 2D coordinate system

`height_2d`

The height of the 2D coordinate system

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pub fn view_2d_in_perspective(
    &mut self,
    fov_y: f32,
    aspect: f32,
    z_near: f32,
    z_2d: f32,
    width_2d: f32,
    height_2d: f32
)

Multiplies self by a view transform that maps the 2D coordinates (0,0) top left and (width_2d,height_2d) bottom right the full viewport size. Geometry at a depth of 0 will now lie on this 2D plane.

Note: this doesn’t multiply the matrix by any projection matrix, but it assumes you have a perspective projection as defined by passing the corresponding arguments to Matrix::perspective.

Toolkits such as Clutter that mix 2D and 3D drawing can use this to create a 2D coordinate system within a 3D perspective projected view frustum.