Difference between revisions of "gc:fillArc"

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(Created page with "__NOTOC__ gc:'''fillArc''' is a function that is part of gc (Graphics Context). Draws a color-filled arc in the rectangle with upper left corner (x,y) and ...")
 
(See Also my edit at gc:drawArc. The original article stated that the last argument was the ending angle, however, this is the angle over which the rountine turns, so 180 will always result in a semicircle))
 
(One intermediate revision by one other user not shown)
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gc:'''fillArc''' is a function that is part of [[:Category:gc|gc]] (Graphics Context).  
 
gc:'''fillArc''' is a function that is part of [[:Category:gc|gc]] (Graphics Context).  
 
    
 
    
Draws a color-filled arc in the rectangle with upper left corner (x,y) and pixel ''width'' and ''height''. The arc is drawn beginning at ''startAngle'' degrees and ending at ''endAngle''.<br />
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Draws a color-filled arc in the rectangle with upper left corner (x,y) and pixel ''width'' and ''height''. The arc is drawn beginning at ''startAngle'' degrees and turns over ''turnAngle'' degrees.<br />
 
Zero degrees points to the right and 90 degrees points up (standard mathematical practice but worth mentioning since the y axis is inverted).     
 
Zero degrees points to the right and 90 degrees points up (standard mathematical practice but worth mentioning since the y axis is inverted).     
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{{Since|3.0}}
 
{{Since|3.0}}
  
 
== Syntax  ==
 
== Syntax  ==
gc:'''fillArc'''(x, y, width, height, start angle, finish angle)  
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gc:'''fillArc'''(x, y, width, height, start angle, turn angle)  
  
 
{| class="wikitable"
 
{| class="wikitable"
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| <u><center>height</center></u> || number || Height of the rectangle containing the arc
 
| <u><center>height</center></u> || number || Height of the rectangle containing the arc
 
|-
 
|-
| <u><center>start angle</center></u> || number || start angle
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| <u><center>start angle</center></u> || number || The starting angle of the arc
 
|-
 
|-
| <u><center>finish angle</center></u> || number || finish angle
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| <u><center>turning angle</center></u> || number || The angle over which the arc turns
 
|}
 
|}
  
== Example ==
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In this syntax ''turnAngle'' can be negative. This means the arc will be drawn clockwise, whereas a positive number results in an arc turning counterclockwise. (Standard mathematical practice as well.)
<syntaxhighlight>gc:fillArc(10, 10, 20, 30, 0, 120)</syntaxhighlight>
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== Examples ==
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<syntaxhighlight>gc:drawArc(10, 10, 20, 30, 0, 120)</syntaxhighlight>
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The syntax above fills an arc from the right to the point turned 120 degrees.
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<br /><br />
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<syntaxhighlight>gc:drawArc(50, 50, 25, 25, 90, 180)</syntaxhighlight>
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The syntax above fills a semicircle from the top to the bottom, turning counterclockwise while doing so. Resulting in the semicircle being on the left side.
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<syntaxhighlight>gc:drawArc(50, 50, 25, 25, 90, -180)</syntaxhighlight>
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The syntax above fills a semicircle as well. Again from the top to the bottom. This time however, the routine will turn the arc clockwise, resulting in the semicircle being on the right side.
  
 
== Good to know ==
 
== Good to know ==
To draw a circle, the width and height must be equal length and the start and end angles must be 0 and 360. If width and height are different lengths, this routine will draw an oval.
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To draw a circle, the width and height must be equal length and the turning angle must be 360. If width and height are different lengths, this routine will draw an oval. It is standard procedure to set the starting angle at 0 degrees. However, this is not necessary.
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Any number over 360 set for ''startAngle'' will roll back to be within the domain of [0,360].
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Any number over 360 set for ''turnAngle'' will have no influence. All numbers higher than 360 will result in a circle.
  
 
== See Also ==
 
== See Also ==

Latest revision as of 10:37, 13 February 2019


gc:fillArc is a function that is part of gc (Graphics Context).


Draws a color-filled arc in the rectangle with upper left corner (x,y) and pixel width and height. The arc is drawn beginning at startAngle degrees and turns over turnAngle degrees.
Zero degrees points to the right and 90 degrees points up (standard mathematical practice but worth mentioning since the y axis is inverted).


This has been introduced in TI-Nspire OS 3.0 (Changes).


Syntax

gc:fillArc(x, y, width, height, start angle, turn angle)

Parameter Type Description
x
number The x-coordinate of the upper-left point
y
number The x-coordinate of the upper-left point
width
number Width of the rectangle containing the arc
height
number Height of the rectangle containing the arc
start angle
number The starting angle of the arc
turning angle
number The angle over which the arc turns

In this syntax turnAngle can be negative. This means the arc will be drawn clockwise, whereas a positive number results in an arc turning counterclockwise. (Standard mathematical practice as well.)

Examples

gc:drawArc(10, 10, 20, 30, 0, 120)

The syntax above fills an arc from the right to the point turned 120 degrees.

gc:drawArc(50, 50, 25, 25, 90, 180)

The syntax above fills a semicircle from the top to the bottom, turning counterclockwise while doing so. Resulting in the semicircle being on the left side.

gc:drawArc(50, 50, 25, 25, 90, -180)

The syntax above fills a semicircle as well. Again from the top to the bottom. This time however, the routine will turn the arc clockwise, resulting in the semicircle being on the right side.

Good to know

To draw a circle, the width and height must be equal length and the turning angle must be 360. If width and height are different lengths, this routine will draw an oval. It is standard procedure to set the starting angle at 0 degrees. However, this is not necessary.


Any number over 360 set for startAngle will roll back to be within the domain of [0,360].

Any number over 360 set for turnAngle will have no influence. All numbers higher than 360 will result in a circle.

See Also

gc:drawArc