Auto Foreshortening and Perspective - part 1

Auto foreshortening is a method of scaling
and mirroring in perspective
its a pretty basic theory and very simple to do.
As in the example below.. we have a
box (black) and we want
to mirror that box. we cant necessarily
just copy and paste.
so we will start out by drawing an
X within the box (red)
then we will add a line back to our
vanishing point from the center of the X.

Next step is to draw a line from the top right
corner through the
center line on the left making sure it crosses
right at the border of the box
And down to the ground plain (Blue)
so that now gives us the
far side point to build up our
mirrored box (green)
Now this method is not limited to vertical
boxes it will work on any plain
or axis

Ok on we go ..

Ok So this is my first tutorial and its all
about perspective.
These first few boxes are to show
some basic layout and the way i start all my
perspective work other may have a
different approach but this is the way i do it
The first part of this tutorial will
be about working
and building shapes in perspective.

Ok so iv drawn my basic grid out with one vanishing point
just off
the screen to the right. and then lowered the opacity
of the grids to 20%
I then added a box to work from on the ground plain
following all the perspective grind lines
The next step is to find the centre of the box you created
and like with any box to find the center you make an X
within the box.
And then draw in your centre lines based off the X
I then added two vertical lines off the centre lines.
Next you have to decide how tall you want your
shape to be and that will depend on What you are
creating and what your background image is
But lets not get ahead of our selves.

Make sure you are using multiple layers for your
grids and guide lines as they can become
confusing after a while I like to work in different
colors for the grids and guide lines to
make it easier to know where i am.

Creating the basic box is an important step,
If you don't follow the perspective
Grids you laid out to begin with and
the box is off it will be very
Difficult to correct the shape later on
so take some time on this stage.

Ok so the next step of the process is to
beside the shape you are going to make.


once you have an idea of the shape we
will use the pen tool to draw it into
the box on our predefined center line.
And also add in the shape of the object
On the ground plain.

So now using our auto foreshortening
method we will plot the possion on
the opposite side of the center line.

Once you have that top view drawn on
the ground plain we have
to start sectioning the shape off so we
can start to build the 3-D object.

So to make the sections through the shape
i draw in the lines within the shapes
boarders try and treat the topview
shape as if it were
a shadow you can then easily know what
your outer limit is for
the main cut lines

now the shape you make it is entirly
up to you. all you have to make
sure of is that you stay inside the boarders.

depending on the possision of your object
in space you may not need the other
sides cut lines, As in my shape. the angle
is so low that the other side
of the shape would be hidden but i put
them in there most of the time
so if i have to add parts that what im
drawing its allready there and im not
guessing as to were to start.