CVT() Function - Pixel, Character, and Semicharacter Unit Conversion
Syntax
CVT(unit_value,conversion_type{,ERR=lineref})
Description
For BBj-specific information, see CVT() Function - BBj.
The CVT() function converts units between pixel, character, and semicharacter formats.
|
Parameter |
Description |
|---|---|
|
unit_value |
An integer that indicates the value of the unit to convert. |
|
conversion_type |
An integer that indicates the type of unit conversion, identified in the table below. |
|
ERR=lineref |
Branch to be taken if an error occurs during execution. |
Values for conversion_type Parameter
|
Value |
Converts from |
Converts to |
Remainder |
|---|---|---|---|
|
0 |
Horizontal pixels |
Horizontal semicharacters |
Truncated |
|
1 |
Vertical pixels |
Vertical semicharacters |
Truncated |
|
2 |
Horizontal pixels |
Horizontal characters |
Truncated |
|
3 |
Vertical pixels |
Vertical characters |
Truncated |
|
4 |
Horizontal pixels |
Horizontal semicharacters |
Rounded |
|
5 |
Vertical pixels |
Vertical semicharacters |
Rounded |
|
6 |
Horizontal pixels |
Horizontal characters |
Rounded |
|
7 |
Vertical pixels |
Vertical characters |
Rounded |
|
8 |
Horizontal semicharacters |
Horizontal characters |
Rounded |
|
9 |
Vertical semicharacters |
Vertical characters |
Rounded |
|
10 |
Horizontal semicharacters |
Horizontal characters |
Truncated |
|
11 |
Vertical semicharacters |
Vertical characters |
Truncated |
|
12 |
Horizontal semicharacters |
Pixels |
N/A |
|
13 |
Vertical semicharacters |
Pixels |
N/A |
|
14 |
Horizontal characters |
Horizontal semicharacters |
N/A |
|
15 |
Vertical characters |
Vertical semicharacters |
N/A |
|
16 |
Horizontal characters |
Pixels |
N/A |
|
17 |
Vertical characters |
Pixels |
N/A |
Vertical and Horizontal Character and Semicharacter Dimension Definitions
The following defines vertical and horizontal characters and semicharacters listed in the previous table:
|
Character |
Definition |
|---|---|
|
Horizontal Character |
Width of the average character in the system font. |
|
Horizontal Semicharacter |
One-fourth the width of an average character in the system font. |
|
Vertical Character |
Height of the system font characters. |
|
Vertical Semicharacter |
One-eighth the height of the system font. |
Example
The following example converts horizontal pixels to horizontal semicharacters and vertical pixels to vertical semicharacters:
rem define a string template for the WININFO control sub-string
tdef$="class:u(1),type:u(1),flags:u(4),id:u(2),x:u(2),y:u(2),w:u(2),"
tdef$=tdef$+"h:u(2),reserved:u(2),sibling:u(2),name:c(10*=0),"
tdef$=tdef$+"title:c(10*=0)"
dim control$:tdef$
rem window_data$ is a string returned by WININFO
rem start is the offset to the current control sub-string
control$=window_data$(start)
rem WININFO always returns pixel values for a control's x, y, width and
height
rem convert the horizontal pixels to horizontal semi-chars rounding any
remainder
semi_char_x=cvt(control.x,4)
semi_char_w=cvt(control.w,4)
rem convert the vertical pixels to vertical semi-chars rounding any remainder
semi_char_y=cvt(control.y,5)
semi_char_h=cvt(control.h,5)