According to Dictionary.com, linear perspective is "a mathematical system for representing three-dimensional objects and space on a two-dimensional surface by means of intersecting lines that are drawn vertically and horizontally and that radiate from one point (one-point perspective), two points (two-point perspective), or several points on a horizon line as perceived by a viewer imagined in an arbitrarily fixed position." http://dictionary.reference.com/browse/one-point+perspective This concept is a powerful tool in a designer's arsenal. Yet, many avoid it because they feel it is too daunting and complicated. Fortunately, an artist doesn't need to do any significant amount of math to master perspective in their drawings. This how to understand perspective in drawing page will show you how to handle the subject with easy to follow diagrams and instructions.

You will need to have at least a basic comprehension of drawing to complete this tutorial. Although the examples are created in Adobe Flash, the principles are valid for any medium whether it be an image editor or pencil and paper. Give yourself 30 to 45 minutes to finish the tasks below.

This article will cover the three different types of linear perspective. They are called one, two and three point perspective. Then, you will go through each of the basic shapes and see how to make them in each setting. Finally, you will find out how to combine it all to make complex scenes which have shapes that always look proper and realistic within their manufactured 3D environment.

To begin, you need to understand two specific terms. The horizon line is a horizontal line that crosses your image and literally represents the horizon between sky and land. The default position of it in a picture is at the eye level of the main subject. Often, you will not actually see this line in a finished drawing because it was just used as a foundation.

Another term you will become familiar with is vanishing point. On the horizon line, there will rest a point at which all diagonal lines converge. The lines that radiate from it will form the guides needed to render objects in perspective. As shapes get closer to the point, they get smaller and visually more distant.

• One Point Perspective:

Definition: Articulation defines it as "a devised drafting technique using straight lines that converge to a single vanishing point on the horizon line. This gave the illusion of three dimensional space on a two dimensional surface.http://gigaweb.brigantine.atlnet.org/ARTiculationFinal/MainPages/O-RVocabulary.htm
• Has only one vanishing point on the horizon line.
• One face is always toward the viewer.
• Vertical lines are perpendicular to the horizon.
• Horizontal lines are parallel to horizon.

• Application:

1. Draw a horizontal line across the middle of the page with the line tool.
2. Place a red dot in the middle with a round brush.
3. Using the rectangular shape tool, draw a white rectangle then give it a 2 pixel black stroke on its own layer.
4. To make your guide lines, activate the line tool and give it a 1 pixel red value. Create a new layer beneath your square. Draw a line from each corner of the square to the vanishing point.
5. On the square layer, use the red lines as a foundation to create the horizontal and vertical edge on the back of the cube. Hold shift when making the lines with a black 2 pixel weight.
6. Make a new layer then trace the red diagonal lines to make the cube's edges.

• Two Point Perspective:

Creative Glossary Definition: "In two-point perspective, there exist two points from which an object’s lines radiate from; the sides of the object vanish to one of two vanishing points on the horizon line. An object’s vertical lines do not relate to the perspective rules of the horizontal lines." http://www.creativeglossary.com/art-perspective/two-point-perspective.html
• Has two vanishing points on the horizon line.
• One edge is always toward viewer.
• Vertical lines are perpendicular to the horizon.
• Purely horizontal lines are rare.

• Application:

1. Draw a horizontal line across the middle of the page with the line tool.
2. With a red round brush, place a dot near both edges of the line.
3. Draw the front vertical edge of your box with a 2 pixel black stroke on its own layer.
4. To make your guide lines, activate the line tool and give it a 1 pixel red value. Create a new layer beneath your initial line. Draw a line from each vanishing point to intersect with the top and bottom edge of the line.
5. On the initial line layer, use the red lines as a foundation to create the other two vertical edges of the cube. Hold shift when making the lines with a black 2 pixel weight.
6. Back on your guide line layer, connect red lines to the new black lines.
7. Make a new layer then trace the red diagonal lines that make the top of the cube with a 2 pixel black line.

• Three Point Perspective:

Creative Glossary Definition: "All of types of linear perspectives include a horizon line and a stationary point (the position of the observer). In three-point perspective there are also two vanishing points somewhere on the horizon; however, unlike two-point perspective, there also exists a vanishing point above or below the horizon line that the vertical lines disappear to." http://www.creativeglossary.com/art-perspective/three-point-perspective.html
• Has two vanishing points on the horizon line and 1 point above or below it.
• If the third point is above the horizon, it is called a worm's eye view. It is like seeing an object from an extreme distance below.
• If the third point is below the horizon, it is called a bird's eye view. It is like seeing an object from an extreme distance above.
• One edge is always toward viewer.
• Purely horizontal or vertical lines are rare.

• Application:

1. Draw a horizontal line across the middle of the page with the line tool.
2. With a red round brush, place a dot near both edges of the line. Then, put a red dot 2/3 the way down the middle of the page.
3. Draw the front straight edge of your box with a 2 pixel black stroke on its own layer.
4. To make your guide lines, follow the same steps for two point perspective. Add the third guides by drawing lines from the third point that intersect with the other guide line crossings.
5. Trace over all the relevant lines in black. Refer to the diagram for clarification.

As you saw demonstrated in the previous section with cubes, you can easily use the lines created from your vanishing point to make any shape you need. Below you will draw each of the basic geometric shapes in one point perspective mode. Before you begin, be sure that you can make cubes well since parts of the other forms are based on the cube and square.

• Cylinder:
• It is composed of a wrapped plane with two circles for end faces instead of two squares like the cube. To create it, make a cube in perspective as a guide. Draw a circle inside the square face. You can also draw diagonals inside the the square to find the midpoint. Refer to the diagram.

• Pyramid:
• Use a cube as the foundation. Find the midpoint for the top point by creating X shaped diagonals in the top face of the cube. Join this midpoint to the lines of the bottom square.

• Cone:
• This is the same as the pyramid. However, you need to make a circle base like that created with the cylinder.

• Sphere:
• Draw a cone as the guide shape. Using the sides of the bottom of the cone and the sides, make a new circle. You'll need to use shading to distinguish it. Try a radial gradient.

• Plane:
• The simplest structure is the plane which is just one side of a cube. To make one, just draw a line the length you need for it then draw your diagonals.

Note: These techniques apply to two and three point perspective as well.

Now that you can make all the foundation shapes, you need to move on to the next level. There won't be many occasions that call for simple blocks on a page. For that reason, you need to understand how figures interact with each other when it concerns perspective. Beyond that, you can see how you can convey a change in mood just by changing the vanishing point level.

• Dealing with People:

• Designate one character as the size barometer for everything else on the page.
• Line the horizon up with the eyes of your main character for a general scene.
• :*If your second character is twice as tall as your main, that ratio will remain along the perspective lines.
• When drawing people, the perspective process is the same as creating a simple cube.

• Shadows:
• You can draw more accurate shadows by using a point to represent your light source. Then, create guide lines from it that intersect with your regular guides. Refer to the diagram.

• How to Use Three Point Perspective to Enhance Scenes:

• Bird's-Eye View: This one can be used for aerial shots and flying hence the name. It can convey vastness and show large areas or groups at once. Also, you can create a clandestine atmosphere for spies and stalkers.
• Worm's-Eye View: In this form, you are looking upwards. It works well for scenes with insects, small creatures and humans in the company of giants. This view also gives the impression of a dark mood or intimidation. It can give the feeling of falling as well.