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Perspective Drawing Boxes

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					Perspective                                                               Drawing Boxes
One point: ‘when parallel lines appear to converge and disappear at       One Point: You have three kinds of lines in one point
one point on the horizon.’                                                perspective—vertical lines, horizontal lines, and perspective
Two Point: ‘when, from a given edge, parallel lines converge at two       lines.
single points on the horizon line at opposite sides of your paper.’       Two Point: Easiest to draw. You have only two kinds of lines—
Three Point: ‘when lines appear to converge at three given points
                                                                          perspective lines or vertical lines.
either to the sides of the picture plane or at the top or bottom of the
                                                                          Three Point: There is only one kind of line in three-point
page, depending on where your eye level line is.’
                                                                          perspective—perspective lines.




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                                                                         Units of Measurement
Dividing a Square
                                                                         Usually measured in Height x Width x Depth
The best way to divide a square in perspective is to draw a diagonal
line from corner to corner. The two diagonal lines intersect at the
centre of the Square.

Adding Squares
Make diagonal lines to find the centre of the square. Use this to find
the middle of the edges. Create another diagonal line from one
corner to the bottom perspective line, intersecting the middle of
the outside edge.




                                                                         Figure 1: This cube is 10 units tall x 5 units wide x 10 units deep




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Multiplying Squares
Just stack cubes on top of one another or next
to one another to draw larger, more
complicated objects.

                                                 Different Views
                                                 When drawing buildings for architecture, you
                                                 show different views of the proposed
                                                 building—front view, side view, and top view.
                                                 If you look down, directly on top of your box,
                                                 you see the top view of the building. If you
                                                 look at one side, you see the side view, and so
                                                 on.




                                                                                                   Visualizing the Object
                                                                                                   This section contains the top, front, and side views of
                                                                                                   many different objects. You need to learn how to
                                                                                                   visualize those objects as they really look. In other
                                                                                                   words, you need to recognize the three-dimensional
                                                                                                   object by seeing the two-dimensional top, front, and
                                                                                                   side views. (Hint: Hidden lines are indicated by a
                                                                                                   dashed line. These dashed lines are edges that you
                                                                                                   cannot see from the view that you are looking at.)




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The cube method                             Drawing Basic Shapes
If you can draw a cube, then you can        All objects are made up from
apply the cube method to draw other         four basic shapes—cube,
objects. For example, you can create a      sphere, cylinder, or cone. You
chair by stacking two cubes, one on top     can use the box method to
of the other, and then erasing the lines.   accurately draw these shapes
                                            to round out your body of
Similarly, a couch can be drawn by          knowledge of all basic shapes
stacking three or four chairs one after     needed to create accurate
the other.                                  drawings. If you learn to see
                                            objects as basic shapes, you will
                                            more easily be able to draw the
                                            objects.

                                            Circles and Ellipses
                                            To draw a perfect circle, first draw a square and then draw a circle
                                            inside the square. Draw diagonal lines from the midpoint of the sides
                                            of the square. Plot a point 1/3 in from the corner on the diagonal.
                                            Now draw a gentle curve that passes through the points 1/3 in on the
                                            diagonals and touches all four midpoints of the sides of the square.




                                            Drawing an ellipse is a simple process. Begin by drawing a
                                            perfect circle using the previous technique, except draw the
                                            square in perspective this time. When drawn in perspective, the
                                            circle in the square is an ellipse.




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Spheres                                                                      The Grid Method
To draw an accurate sphere, begin by drawing a cube. Then draw two           The grid method is a way of enlarging, reducing or putting in
dissecting planes that cut the cube in half both vertically and              perspective any object that you draw. Place a grid over the drawing
horizontally. Draw ellipses within the planes in the square. Touch the       and then make a new grid apart from your drawing. Finish transferring
mid-points of the squares within the cube.                                   the drawing square by square from the old grid to the new one.
                                                                             If you want to move the drawing in perspective, draw the grid in
                                                                             perspective.




Cylinders and Cones
To draw a cylinder, begin by drawing a box in perspective. Then draw
ellipses on opposite sides of the box. Connect these circles with straight
lines to form a cylinder as in the following
illustration.


                                                                             Shading
                                                                                •   Shading gives form to objects.
                                                                                •   The principle is simple, the closer to the direct light source,
Drawing a cone is similar to drawing a cylinder, except this time draw an           the lighter the tone of the object.
ellipse on only one side of the box. Find the midpoint on the opposite          •   In order to simplify drawing, only use four types of shading on
side of the box, and draw lines from the midpoint to the edges of the               an object: light, light gray, dark gray, black.
circle. You now have a cone as shown here.




Contour Lines

                                    Contour lines are lines that wrap
                                    around objects to depict what the
                                    surface of the objects’ like.




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Curved Surfaces                              Shadows                                                   Drawing shadows for
Shading a curved surface is like shading a   A shadow is the base of                                   complicated objects:
plane surface. The only difference is that   a triangle formed by                                      The cast shadow of complicated objects is
shading gradually changes from light to      the direction of the                                      drawn the same way as for simple objects
dark. Curved surfaces do not have distinct   light source and the                                      described above.
edge to separate the value tones of the      object.
shading.

                                             How to draw a cast shadow:
                                             First determine the angle of the light source. Draw the
                                             triangle from the edges of the object and the light
                                             source. Connect the bases of the triangles, and darken    Shadows over objects:
                                             in the cast shadow area
                                                                                        Notice in the following example how the
                                                                                        cast shadow appears to be shorter where it
                                             Drawing the cast shadow for a simple cube: crosses the smaller cube. This occurs
                                                                                        because the triangle crosses the cube
                                                                                        higher up so that the base of the triangle is
                                                                                        shorter.
Light against Dark
Good drawing employs the principle of
continuous light against dark. Make the
distinction between the background and
foreground to make a drawing clear. Begin
by drawing the dark and then proceed to
the lighter shades.




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Reflections                                      Special Case #1: An object sitting exactly on a reflective surface
Why are they useful?                             As seen, the reflection begins at the baseline and is a mirror image.
  • When buildings are located near water
  • Home & office products contain chrome
       and shiny surfaces that show reflection
  • Glass windows and mirrors
  • Add reality to the drawings
  • Can show parts of the object not seen
       without reflection

How to draw a reflection?
It is a mirror image of the object.              Special Case #2: An object is above the reflecting surface
Measurements of the reflection are the same as
those on the object




                                                 As seen, the distance between the base of the object and the surface is accounted for as
                                                 indicated by the dotted line and the arrows.

                                                 Colors
                                                 For most architectural and engineering drawings, color is sparingly used
                                                 Use it only to emphasize key points – use no more than three colors
                                                 Light colors advance—they punch out. Dark colors recede—they appear to be holes.




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