... in a classroom of thirty odd students that is called living on the edge. But then again I am easily bored; anyway, remember our railway line in a previous lesson?
Move the vanishing point along the horizon line to the right as above. Just use common judgment to place the sleepers ... as you might do in any grammar class.
Of course, as the line bends, it does with a 'curve'. Draw in the freehand curve as shown.
Next, we find a vanishing point 'above' the horizon! This will have the effect of making the line appear to rise up. See above.
Then go down again ... with a vanishing point now below the line.
Firm in the lines and explain that every 'regular' object can be
placed in space to have its own vanishing point.
Here we have merely joined a few together.
Students construct margin and title box on a new page then:
a) In approximate positions, as above, lightly construct a road bending to the right and descending. ...
b) Firm in until the curves transcend the horizontal ...
c) and add a nice curving hill.
d) Change direction and do the same thing again. Your own 'judgment'
should be used to determine the 'new' width of the road.
Logically it must be smaller than its width as it disappears
over the first hill. Point out that this width will determine
just how far the first hill is from the second.