ONE POINT PERSPECTIVE
One-point perspective is when all the major lines of an image converge on one point. You can see this effect best illustrated when looking down a set of straight railroad tracks or a long road. The lines of the road and track, although we know they are the same distance apart, seem to meet and join together at some point in the far distance – the vanishing point. In one-point perspective all the lines move away from you (the z-axis) and converge at the vanishing point. Vertical and horizontal or up and down and right and left lines (X and Y) remain straight. As discussed in the previous section, we know that lines which are parallel to one another, and recede into the depth of the picture toward the horizon, will all meet at one point on the horizon line. This point is the vanishing point and is used for all objects in one-point perspective. Also, we have one-point perspective when both the height and width of an object are parallel to the picture plane. When an object is placed in this position it is viewed straight on. The edges of the front, top, bottom and sides of the object are parallel to the edges of the picture plane. They have no depth; therefore, they have no lines that extend to a vanishing point.
The surfaces, such as the sides, top and bottom, that extend into the picture creating the illusion of depth have imaginary lines that will join at the vanishing point on the horizon line. When looking at a cube straight on, we see that the edges of the top extend into the picture and meet at the vanishing point, giving illusion of depth.
One-point perspective images have a tendency to draw the viewer along the lines to the vanishing point. This effect can be used to greater advantage by placing the subject of an image in front of or near the vanishing point. The viewers will more naturally focus their attention because most of the lines in the image converge onto that area. The boxes to the left to the tracks in the one-point perspective example have one face perfectly aligned parallel to the picture plane. This is a limitation of one point perspective. Another problem with this technique is that objects become more distorted the further they are from the vanishing point, as can be seen with the far left box in the example.
One-Point parallel perspective drawing consists of a horizon line, one vanishing point placed on the horizon line and the understanding that all horizontal lines drawn will be parallel to each other. The X, Y, Z lines are axis lines. It is important to note, the x-axis line is parallel to the horizon line. The z-axis is at a 90-degree angle to the x-axis line. Now, converging at a single vanishing point on the horizon line is the y-axis lines. This arrangement of axis ONLY works for one point perspective.
Drawing Cube in One-Point Perspective:
Step1: Lightly sketch the general shape of the face of the cube.
Step2: Lightly draw the two angle lines along the top until they cross.
Step3: At the point where they cross, draw a horizontal line parallel to the top and bottom lines of the cube. This is the horizon line. Now place a vanishing point where the lines cross. (This is the way to find the horizon line and vanishing point using the angles from an object such as a cube, a table etc…)
Step4: draw a parallel line between the horizon line and the top of the cube. This establishes the top surface of the cube. Darken the lines. Here is a cube drawn in perfect one-point perspective.
The train tracks are an example of one-point perspective, the easiest of the perspective methods. This method is useful when representing landscapes, city streets, and other environments in which things are aligned and converge to one central point.