change
Sets the current font matrix to a scale by a factor of size, replacing any font matrix previously set with changeFontSize or cairo_set_font_matrix. This results in a font size of size user space units. More precisely this matrix will result in the font's em-square being a size by size square in user space. If text is drawn without a call to changeFontSize (nor cairo_set_font_matrix nor cairo_set_scaled_font) then the default font size is 10.0.
Parameters
size
The new font size in user space units.
Parameters
size
The new font size in user space units.
Parameters
size
The new font size in user space units.