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Perspective Functions

void persp_0 (const real front_corner_x, const real front_corner_z, const real side_lft, const real side_rt, const real angle_rt, const real f_2_cv, const real gl_2_cv, [const real horizon_lft = 6, [real horizon_rt = 0, [real gl_lft = 0, [real gl_rt = 0]]]]) Function
Defined in utility.web. This function is used for the figure in The Perspective Projection, illustrating a perspective projection as it could be done by hand. It draws a rectangle in the ground plane and the construction lines used for putting it into perspective. It also labels the vanishing and measuring points.

The arguments:

const real front_corner_x
The x-coordinate of the front corner of the rectangle.
const real front_corner_z
The z-coordinate of the front corner of the rectangle.
const real side_lft
The length of the left side of the rectangle.
const real side_rt
The length of the right side of the rectangle.
const real angle_rt
The angle at which the right side of the rectangle recedes to the horizon.
const real f_2_cv
The distance from the focus to the center of vision.
const real gl_2_cv
The distance of the ground line to the center of vision.
const real horizon_lft
Default: 6. The length of the horizon line leftwards of the center of vision.
real horizon_rt
Default: 0. The length of the horizon line rightwards of the center of vision.
real gl_lft
Default: 0. The length of the ground line leftwards of the line from the focus to the center of vision.
real gl_rt
Default: 0. The length of the ground line rightwards of the line from the focus to the center of vision.

Example:

          persp_0(3, 2, 10, 5, 47.5, 7, 5, 8.5, 9.5, 8.5, 9.5);
          


[Figure 199. Not displayed.]

Fig. 199.