Matrix package:gi-pango
A
PangoMatrix specifies a transformation between user-space
and device coordinates.
The transformation is given by
x_device = x_user * matrix->xx + y_user * matrix->xy + matrix->x0;
y_device = x_user * matrix->yx + y_user * matrix->yy + matrix->y0;
Since: 1.6
Memory-managed wrapper type.
Changes the transformation represented by matrix to be
the transformation given by first applying transformation given by
newMatrix then applying the original transformation.
Since: 1.6
Copies a PangoMatrix.
Since: 1.6
Free a PangoMatrix.
Since: 1.6
Returns the scale factor of a matrix on the height of the font.
That is, the scale factor in the direction perpendicular to the vector
that the X coordinate is mapped to. If the scale in the X coordinate
is needed as well, use
matrixGetFontScaleFactors.
Since: 1.12
Calculates the scale factor of a matrix on the width and height of the
font.
That is, xscale is the scale factor in the direction
of the X coordinate, and yscale is the scale factor in
the direction perpendicular to the vector that the X coordinate is
mapped to.
Note that output numbers will always be non-negative.
Since: 1.38
Gets the slant ratio of a matrix.
For a simple shear matrix in the form:
1 λ 0 1
this is simply λ.
Since: 1.50
Changes the transformation represented by matrix to be
the transformation given by first rotating by degrees
degrees counter-clockwise then applying the original transformation.
Since: 1.6
Changes the transformation represented by matrix to be
the transformation given by first scaling by sx in the
X direction and sy in the Y direction then applying
the original transformation.
Since: 1.6
Transforms the distance vector (
dx,
dy)
by
matrix.
This is similar to
matrixTransformPoint, except that the
translation components of the transformation are ignored. The
calculation of the returned vector is as follows:
dx2 = dx1 * xx + dy1 * xy;
dy2 = dx1 * yx + dy1 * yy;
Affine transformations are position invariant, so the same vector
always transforms to the same vector. If
(
x1,
y1) transforms to
(
x2,
y2) then
(
x1+
dx1,
y1+
dy1)
will transform to
(
x1+
dx2,
y1+
dy2)
for all values of
x1 and
x2.
Since: 1.16
First transforms the
rect using
matrix, then calculates the bounding box of the
transformed rectangle.
This function is useful for example when you want to draw a rotated
pangoLayout to an image buffer, and want to know how
large the image should be and how much you should shift the layout
when rendering.
For better accuracy, you should use
matrixTransformRectangle on
original rectangle in Pango units and convert to pixels afterward
using [func
extentsToPixels]'s first argument.
Since: 1.16
Transforms the point (x, y) by
matrix.
Since: 1.16
Changes the transformation represented by matrix to be
the transformation given by first translating by (tx,
ty) then applying the original transformation.
Since: 1.6
Gets the transformation matrix that will be applied when rendering
with this context.
See
contextSetMatrix.
Since: 1.6
Sets the transformation matrix that will be applied when rendering
with this context.
Note that reported metrics are in the user space coordinates before
the application of the matrix, not device-space coordinates after the
application of the matrix. So, they don't scale with the matrix,
though they may change slightly for different matrices, depending on
how the text is fit to the pixel grid.
Since: 1.6
Gets the transformation matrix that will be applied when rendering.
See
rendererSetMatrix.
Since: 1.8
Sets the transformation matrix that will be applied when rendering.
Since: 1.8
Get the value of the “
x0” field. When
overloading is
enabled, this is equivalent to
get matrix #x0
Get the value of the “
xx” field. When
overloading is
enabled, this is equivalent to
get matrix #xx
Get the value of the “
xy” field. When
overloading is
enabled, this is equivalent to
get matrix #xy
Get the value of the “
y0” field. When
overloading is
enabled, this is equivalent to
get matrix #y0
Get the value of the “
yx” field. When
overloading is
enabled, this is equivalent to
get matrix #yx
Get the value of the “
yy” field. When
overloading is
enabled, this is equivalent to
get matrix #yy