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);
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Fig. 199.