I am trying to draw some guide-lines on top of my image in my image-view using bgl.

But when I draw the coordinates of my shape/line is relative to the screen/view when I actually want what I draw to always be on top of my image in the image-view.

Is there any way to extract the image position to transform my shape to always be on my image or is there any other way to do this?


So I solved this, it appears that the image editor is also like a 3d coordinate system. So I followed a tut for 3D and then just changed the view to SpaceImageEditor and instead of drawing on 'POST_PIXEL' I drew to 'POST_VIEW'. Code:

def __init__(self):
    self.draw_handle = None
    self.draw_event = None

    self.widgets = []

def invoke(self, context, event):


    args = (self, context)
    self.register_handlers(args, context)

    return {'RUNNING_MODAL'}

def register_handlers(self, args, context):
    self.draw_handle = bpy.types.SpaceImageEditor.draw_handler_add(self.draw_callback, args,'WINDOW', 'POST_VIEW')

    self.draw_event = context.window_manager.event_timer_add(0.1, window=context.window)

def unregister_handlers(self, context):

    bpy.types.SpaceImageEditor.draw_handler_remove(self.draw_handle, 'WINDOW')

    self.draw_handle = None
    self.draw_event = None

def modal(self, context, event):
    if context.area:

    if event.type in {'ESC'}:
        return {'CANCELLED'}

    return {'PASS_THROUGH'}

def finish(self):
    return {'FINISHED'}

def create_batch(self):

    vertices = [(0, 0.5, 0), (1, 0.5, 0)]

    self.shader = gpu.shader.from_builtin('3D_UNIFORM_COLOR')
    self.batch = batch_for_shader(self.shader, 'LINE_STRIP', {'pos': vertices})

def draw_callback(self, op, context):

    self.shader.uniform_float('color', (1,0,0,1))

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