Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Disclosed is a tool for defining the length of a segment by relating it to an existing segment in an interactive computer graphics system.
a tool for defining the length of a segment
by relating it to an existing segment in an interactive computer
When the user
is drawing a segment, he can get an electronic
divider on the display, as shown in Fig. 1, by pushing the "Set
Length" button and selecting a reference segment from the existing
segments. The electronic divider is parallel to the segment being
drawn at that time (P3-P4), and its starting point is located on the
starting point of this segment (P3). There are large graduations (R1,
R2, ...) and small graduations (Q1, Q2, ...) on the electronic
divider. The distance between adjacent large graduations (R1-R2) is
the same as the length of the segment P1-P2, because the user has
selected P1-P2 as the reference segment. The distance between small
graduation (Q1) and large graduation (R1) is the same as half the
length of the segment P1-P2.
The user can
select the position of a large or small graduation
by dragging the handle of the electronic divider. By selecting the
position of the graduation as Q1, R1, Q2, or R2, the user can set the
length of P3-P4 as 0.5, 1.0, 1.5, or 2.0 times the length of the
reference segment P1-P2, respectively.
"2" on the control panel is the current dividing
ratio of the electronic divider. By pushing the "Up" or "Down"
button, he can change the ratio and the positions of the small
graduations (Fig. 2). In this way, he can set...