darktable.guides

table

Guide lines to overlay over an image in crop and rotate. All guides are clipped to the drawing area.

🔗darktable.guides.register_guide

function(
  name : string,
  draw_callback : function,
  [gui_callback : function]
)

name - string - The name of the guide to show in the GUI.
draw_callback - function - The function to call to draw the guide lines.
[gui_callback] - function - A function returning a widget to show when the guide is selected. It takes no arguments.

draw_callback -

function(
  cr : types.dt_lua_cairo_t,
  x : float,
  y : float,
  width : float,
  height : float,
  zoom_scale : float
)

The function to call to draw the guide lines. The drawn lines will be stroked by darktable. THIS IS RUNNING IN THE GUI THREAD AND HAS TO BE FAST!

cr - types.dt_lua_cairo_t - The cairo object used for drawing.
x - float - The x coordinate of the top left corner of the drawing area.
y - float - The y coordinate of the top left corner of the drawing area.
width - float - The width of the drawing area.
height - float - The height of the drawing area.
zoom_scale - float -The current zoom_scale. Only needed when setting the line thickness.