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authorscuri <scuri>2010-06-01 22:31:45 +0000
committerscuri <scuri>2010-06-01 22:31:45 +0000
commit17be65cfea56a53dc3a9cb617895adf5300db099 (patch)
tree03362237b113b92157f433ce0e018c39821b1f84 /html/en/func/lines.html
parent3e4bae27558fd3bcec4bc54928b0a5d3145cd7c3 (diff)
*** empty log message ***
Diffstat (limited to 'html/en/func/lines.html')
-rw-r--r--html/en/func/lines.html22
1 files changed, 13 insertions, 9 deletions
diff --git a/html/en/func/lines.html b/html/en/func/lines.html
index b748391..6ba78d7 100644
--- a/html/en/func/lines.html
+++ b/html/en/func/lines.html
@@ -1,5 +1,5 @@
<!doctype HTML PUBLIC "-//IETF//DTD HTML//EN">
-<html>
+<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office">
<head>
<meta http-equiv="Content-Language" content="en-us">
@@ -64,21 +64,25 @@ canvas:fArc(xc, yc, w, h, angle1, angle2: <em>number</em>) [in Lua]
canvas:wArc(xc, yc, w, h, angle1, angle2: <em>number</em>)<font><font> (WC) [in Lua]</font></font></pre>
<p>Draws the arc of an ellipse aligned with the axis, using the current
- foreground color and line width and style. It is drawn counter-clockwise. The
+ foreground color and line width and style.</p>
+<p>The
coordinate <b>(xc,yc)</b> defines the center of the ellipse.
Dimensions <b>w</b> and <b>h</b> define the elliptic axes X
and Y, respectively. </p>
- <p>Angles <b>angle1</b> and <b>angle2</b>, in degrees define
- the arc's beginning and end, but they are not the angle relative to the
+ <p>Angles <b>angle1</b> and <b>angle2</b> are in degrees and oriented
+ counter-clockwise. They define
+ the arc start and end, but they are not the angle relative to the
center, except when w==h and the ellipse is reduced to a circle. The arc
- starts at the point <b><b>(xc+(w/2)*cos(angle1),yc+(h/2)*sin(angle1))</b>
- </b>and ends at <b>(xc+(w/2)*cos(angle2),yc+(h/2)*sin(angle2))</b>.&nbsp;A
- complete ellipse can be drawn using 0 and 360 as the angles. </p>
+ starts at the point <b><b>(xc+(w/2)*cos(angle1), yc+(h/2)*sin(angle1))</b>
+ </b>and ends at <b>(xc+(w/2)*cos(angle2), yc+(h/2)*sin(angle2))</b>.&nbsp;A
+ complete ellipse can be drawn using 0 and 360 as the angles. If <b>angle2</b>
+ is less than <b>angle1</b> it will be increased by 360 until it is greater
+ than <b>angle1</b>. </p>
<p>The angles are specified so if the size of the ellipse (w x h) is changed,
its shape is preserved. So the angles relative to the center are dependent
from the ellipse size. The actual angle can be obtained using <b>rangle =
- atan2((h/2</b><b>)*sin(angle),(w/2)*cos(angle))</b>.</p>
- <p>The angles are given in degrees. To specify the angle in radians, you can
+ atan2((h/2</b><b>)*sin(angle), (w/2)*cos(angle))</b>.</p>
+ <p>To specify the angle in radians, you can
use the definition <font size="2"><strong>CD_RAD2DEG</strong></font>
to multiply the value in radians before passing the angle to CD.</p>
<p align="center"><font size="4">Arc Parameters<br>