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Enter point (0,10,0) in the Coordinates Window and click Apply.
With option Contextual->Join Ctrl-a (mouse menu) click over point 1. A line should be created between (0,10,0) and (0,0,0). Press Escape twice.
With this, a right angle of the square has been defined.
Center the image in the screen with View->Zoom->Frame.
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GiD then asks the user to define the 4 lines that describe the contour of the surface. Select the lines using the cursor on the screen, either by choosing them one by one or selecting them all with a window. Next, press Escape twice.
As can be seen below, the new surface is created and appears as a smaller, magenta -coloured square drawn inside the original four lines.
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We want to concentrate the elements in the left zone of the square.
Select both horizontal lines and press ESC. A window appears to enter the weights values.
Both lines should have the same direction so enter a weight of 0.5 to the beginning of the line and click Ok. Press ESC again to leave the function.
If lines have different direction, to obtain the same result, we should assign the weight for one line to the beginning and to the end for the other line.
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