Whatdotcolor

From Compsci.ca Wiki

Also spelled whatdotcolour (Canadian spelling of colour), it is a Turing function which returns the colour of a specific pixel. Often used for collision detection, it is an easy solution when creating something using Turing graphics alone without external images being involved.

It's actually so important that there's a whatdotcolor Warrior mod.

Here's a quick example of a few basic graphics functions which uses whatdotcolour to check if the mouse is above a red circle. %%Example of whatdotcolour collision detection %%By: Gandalf setscreen ("graphics,offscreenonly") var cx, cy, mx, my, mb : int cx := maxx div 2 cy := maxy div 2 var circleColour : int := red loop

   cls
   Draw.FillOval (cx, cy, 40, 40, circleColour)
   Mouse.Where (mx, my, mb)
   %if your mouse is above the circle and you click
   if whatdotcolour (mx, my) = circleColour and mb > 0 then
       %move the circle to the mouse coordinates
       cx := mx
       cy := my
   end if
   View.Update

end loop

An alternative of whatdotcolour collision detection in Turing is using Math.Distance.