love.graphics.intersectScissor
Sets the scissor to the rectangle created by the intersection of the specified rectangle with the existing scissor. If no scissor is active yet, it behaves like love.graphics.setScissor.

The scissor limits the drawing area to a specified rectangle. This affects all graphics calls, including love.graphics.clear.

The dimensions of the scissor is unaffected by graphical transformations (translate, scale, ...).
love.graphics.intersectScissor( x, y, width, height )
x number The x-coordinate of the upper left corner of the rectangle to intersect with the existing scissor rectangle.
y number The y-coordinate of the upper left corner of the rectangle to intersect with the existing scissor rectangle.
width number The width of the rectangle to intersect with the existing scissor rectangle.
height number The height of the rectangle to intersect with the existing scissor rectangle.