摘要

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根據自由軟體基金會發佈嘅無固定段落、封面文字同封底文字GNU自由文件授權條款第1.2或打後嘅版本，你獲授權可以重製、散佈同埋修改爾份文件。授權條款嘅副本喺章節GNU自由文件授權條款。http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue

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	This licensing tag was added to this file as part of the GFDL licensing update.http://creativecommons.org/licenses/by-sa/3.0/CC BY-SA 3.0Creative Commons Attribution-Share Alike 3.0truetrue

你可以揀你想用嘅牌照。

Source: A quem interessar, o código para geração das três imagens relativas ao artigo pt:Cónicas é o seguinte (deve ser renderizado pelo Polyray, de Alexander Enzman).

viewpoint
{
	from <-30,18,47>
	at <0,6,-1>
	angle 26
	resolution 300,300
}

background <1,1,1>

light white,<0,10,-5>

spot_light white,<-70,20,0>,<-20,10,0>,64,46,40

// Cone semi-transparente que serve de base para ilustrar as secções.
define conecon object
{
	cone <0,0,0>,9, <0,16,0>,0

	texture
	{
		surface
		{
			color <0.6,0.6,0.6>
			transmission .7,1
			ambient .7
			diffuse .4
			brilliance .6
		}
	}
}

// Elipse
define elips1 object
{
	object { box <-80,1,-80>,<80,1.1,80> translate <0,4,0> rotate <20,0,0> }
	* object { conecon }

	texture
	{
		surface
		{
			color <0.5,0.8,0.5>
			ambient .4
			diffuse .2
		}
	}
}

//Parábola - observar que o ângulo do triângulo que gera o cone
// foi arredondado para 74 graus
define parabol1 object
{
	object { box <-80,1,-80>,<80,1.1,80> rotate <0,0,74> translate <1,0,0> }
	* object { conecon }

	texture
	{
		surface
		{
			color <0.5,0.8,0.5>
			ambient .4
			diffuse .2
		}
	}
}

//Hipérbole
define hiperb1 object
{
	object { box <-80,1,-80>,<80,1.1,80> rotate <0,0,90> translate <-2,0,0> }
	* object { conecon }

	texture
	{
		surface
		{
			color <0.5,0.8,0.5>
			ambient .4
			diffuse .2
		}
	}
}

// Insira aqui os objectos que vão compor a cena.