blitz-research
28 lines
1.7 KiB
HTML
28 lines
1.7 KiB
HTML
<html><head><title>Command: ATan </title><meta http-equiv='Content-Type' content='text/html; charset=iso-8859-1'><link rel='stylesheet' href='../css/commands.css' type='text/css'></head><body><span class='Command'> ATan (float) </span></p><span class='header'>Definition:</span> <br><br><table width='100%' border='0' cellspacing='2' cellpadding='2' align='center'><tr><td>Returns the angle from the X axis to a point (y,x).</td></tr></table><span class='header'><br>Parameter Description:</span> <br><br><table width='100%' border='0' cellspacing='2' cellpadding='2' align='center'><tr><td>float = floating point value (degrees)</td></tr></table><p class='header'>Command Description: <br><br><table width='100%' border='0' cellspacing='2' cellpadding='2' align='center'><tr><td>Aside from its basic trig usage, this nifty command will allow you to derive an angle based on the x and y speed of a travelling object. Also see <a href='ATan2.htm'>ATan2</a>.<br>
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</td></tr></table><p class='header'>Example: <br><br><table width='100%' border='0' cellspacing='2' cellpadding='2' align='center'><tr><td>; Set graphics w/double buffering<br>
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Graphics 640,480,16,0<br>
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SetBuffer BackBuffer()<br>
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<br>
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; Starting point for our travelling box<br>
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x=0<br>
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y=0<br>
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<br>
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; random speed values for travelling<br>
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xSpeed#=Rand(5)<br>
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ySpeed#=Rand(5)<br>
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<br>
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; repeat until the ESC or box travels off the screen<br>
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While Not KeyHit(1) Or y > 480 Or x > 640<br>
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Cls<br>
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; Draw our box<br>
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Rect x,y,10,10,1<br>
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; increment the box location based on random speed<br>
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x=x+xSpeed<br>
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y=y+yspeed<br>
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; print the angle of our box travel<br>
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Text 0,0,ATan(yspeed/xspeed)<br>
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Flip<br>
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Wend<br>
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</td></tr></table><p><b><a target="_top" href="../index.htm">Index</a></b></p></body>
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</html>
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