Draw hole in a canvas

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Sling
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Joined: Mon Sep 11, 2017 2:37 pm
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Re: Draw hole in a canvas

#21 Post by Sling »

Keith Baxter wrote: Wed Apr 28, 2021 2:13 pm Hi,

A bit more code but _arc() ,_quad_to() ,_ellipse(), _bezier_to() can be used to create shaped viewports.

Code: Select all

img_cover=canvas_add(0,0,800,400)
  
canvas_draw(img_cover, function()
   _move_to(200,50)
   _line_to(600,50)
   _line_to(600,350)
   _line_to(200,350)
   _line_to(200,0)   
   _line_to(0,0)
   _line_to(0,400)
   _line_to(800,400)
   _line_to(800,0)
   _line_to(199,0)
   _line_to(199,50)
   _line_to(200,50)   
  _fill("red")   
end)
Note how the last three line in the draw overlap. This is to ensure an overlap. In you version there are transparencies where the rectangles join/meet. I suggest you make them overlap a px or two. But you got the idea.

Keith
Be careful calling it a viewport because it’s not a viewport in the AM sense. Just think it may confuse someone reading this at a later date.

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