diff options
Diffstat (limited to 'pango')
| -rw-r--r-- | pango/pango-matrix.c | 34 | ||||
| -rw-r--r-- | pango/pango-matrix.h | 2 |
2 files changed, 36 insertions, 0 deletions
diff --git a/pango/pango-matrix.c b/pango/pango-matrix.c index a066eb57..3bc0ff16 100644 --- a/pango/pango-matrix.c +++ b/pango/pango-matrix.c @@ -263,6 +263,40 @@ pango_matrix_get_font_scale_factors (const PangoMatrix *matrix, } /** + * pango_matrix_get_slant_ratio: + * @matrix: a `PangoMatrix` + * + * Gets the slant ratio of a matrix. + * + * For a simple shear matrix in the form: + * + * 1 λ + * 0 1 + * + * this is simply λ. + * + * Returns: the slant ratio of @matrix + * + * Since: 1.50 + */ +double +pango_matrix_get_slant_ratio (const PangoMatrix *matrix) +{ + double x0, y0; + double x1, y1; + + x0 = 0; + y0 = 1; + pango_matrix_transform_distance (matrix, &x0, &y0); + + x1 = 1; + y1 = 0; + pango_matrix_transform_distance (matrix, &x1, &y1); + + return (x0 * x1 + y0 * y1) / (x0 * x0 + y0 * y0); +} + +/** * pango_matrix_transform_distance: * @matrix: (nullable): a `PangoMatrix` * @dx: (inout): in/out X component of a distance vector diff --git a/pango/pango-matrix.h b/pango/pango-matrix.h index d4277401..cb53a422 100644 --- a/pango/pango-matrix.h +++ b/pango/pango-matrix.h @@ -121,6 +121,8 @@ double pango_matrix_get_font_scale_factor (const PangoMatrix *matrix) G_GNUC_PUR PANGO_AVAILABLE_IN_1_38 void pango_matrix_get_font_scale_factors (const PangoMatrix *matrix, double *xscale, double *yscale); +PANGO_AVAILABLE_IN_1_50 +double pango_matrix_get_slant_ratio (const PangoMatrix *matrix) G_GNUC_PURE; G_END_DECLS |