openscad 3Dmodels 笔记

参考链接

官方文档
官方文档之——代码

如何快速上手

打开openSCAD后界面如下：

选择其中的examples，从basic看起。配合官方文档中的first step部分，和官方文档——代码写法即可很快上手。

概述

• 默认界面左边是代码，右边是预览图
• Ctrl + D 可注释选中行（从edit菜单栏中得知）
• 以下按钮预览（鼠标停留可显示文字preview）
  

命令

几何体

cube(10);  //边长为10的正方体，锚点在其一角
cube([2,3,4]); //长宽高分别为2，3，4的长方体，锚点在其一角
cube(15, center=true);  //边长为15的正方体，锚点在其中心

sphere(10); //半径为10的球体

polygon( points=[[0,0],[8,4],[4,8],[4,12],[12,16],[0,20]] ); //这几个点顺次连接构成的几何体

几何变换

translate([-24,0,0])  //平移
union()  //并
intersection //交
difference() // 差
hull()  //凸包，详情请百度

例子：

linear Extrude

linear_extrude(
height = fanwidth, 
center = true, 
convexity = 10, 
twist = -fanrot,
 slices = 20,
 scale = 1.0, 
$fn = 16) {...}

minkowski() （倒角，圆角，bevel）

例一：minkowski()直接用于三维物体

height = 10;
length = 10;
width = 20;
bevelRadius = 2;

$fn=50;
cube([length-2*bevelRadius, width-2*bevelRadius,height]);
cylinder(r=bevelRadius,h=height);

translate([20,0,0])
    minkowski()
    {
      cube([length-2*bevelRadius, width-2*bevelRadius,height/2]);
      cylinder(r=bevelRadius,h=height/2);
    }

例二：minkowski()用于二维物体（之后可以叠加linear Extrude）

height = 10;
length = 10;
width = 20;
bevelRadius = 2;
linear_extrude(height = height)
    square([length-2*bevelRadius, width-2*bevelRadius]);
linear_extrude(height = height)
          circle(r=bevelRadius);
          
$fn=50;

translate([20,0,0])
linear_extrude(height = height)
        minkowski()
        {
          square([length-2*bevelRadius, width-2*bevelRadius]);
          circle(r=bevelRadius);
        }

效果和例一相同

projection()

projection(cut = true)
          import("projection.stl");

rotate_extrude()

绕z轴旋转360°

文字

官方文档——text用法

text(letter, 
       size=size*22/30,
       font="Bitstream Vera Sans",
       halign="center",
       valign="center");

echo（字符串变量）；

会在右边控制台console中第三行左右显示

导入其他文件

import("xxx.stl");

import("projection.stl");  //

use <xxx.scad>

use <logo.scad>  //Imports the Logo() module from logo.scad into this namespace
Logo();

特殊显示（透明与高亮）

cube(15,center = true);
translate([0, 0, 20]){
    %cube(15,center = true);  //% 是透明
}
    
translate([0, 0, -20]){
    #cube(15,center = true);  //#是高亮
}

效果如图：

特殊变量

分辨率：$fa, $fs and $fn

The $fa, $fs and $fn special variables control the number of facets used to generate an arc:

• $fa is the minimum angle for a fragment. Even a huge circle does not have more fragments than 360 divided by this number. The default value is 12 (i.e. 30 fragments for a full circle). The minimum allowed value is 0.01. Any attempt to set a lower value will cause a warning.

• $fs is the minimum size of a fragment. Because of this variable very small circles have a smaller number of fragments than specified using $fa. The default value is 2. The minimum allowed value is 0.01. Any attempt to set a lower value will cause a warning.

• $fn is usually 0. When this variable has a value greater than zero, the other two variables are ignored and full circle is rendered using this number of fragments. The default value is 0.

初始视角 $vpr, $vpt and $vpd

• $vpr shows rotation
• $vpt shows translation (i.e. won't be affected by rotate and zoom)
• $vpd shows the camera distance [Note: Requires version 2015.03]