计算所需摄像机变倍对象以适应屏幕高度 [英] Calculate camera zoom required for object to fit in screen height

问题描述

在Three.js我用这个公式来计算可视宽度放大器;身高

  VAR VFOV = camera.fov * Math.PI / 180; //转换成垂直视场角为弧度
VAR HEIGHT = 2 * Math.tan（VFOV / 2）* DIST; //可见高度

VAR方面= window.width / window.height;
VAR WIDTH =身高*方面; //可见宽度
 

和与我计算所需的对象相机变焦，从而精确匹配到由宽度渲染面积

  VAR变焦=（ObjectHeight /纵横）/（2 * Math.tan（VFOV / 2））+ ObjectDepth;
 

我如何计算所需的对象，相机变焦，从而精确匹配到由高度渲染区域？

由于GuyGood，我找到了解决办法：

  VAR变焦=（ObjectHeight / 2）/ Math.tan（VFOV / 2） -  ObjectDepth;
 

解决方案

我做的是基于BoundingSphere所半径如下：

  geometry.computeBoundingSphere（）;
半径= geometry.boundingSphere.radius;
distanceFactor = Math.abs（纵横*半径/ Math.sin（FOV / 2）;
 

这是基于这个东西就在这里，我希望我跨preTED的正确方法： HTTP：//www.flip$c$c.com/forums/thread/4172

本 distanceFactor 是你需要移动相机沿其视线方向正确地安装它的因素。目前，我不知道，如果它是由高度或宽度，但也许它可以帮助你看着办吧。 :)

In Three.js I'm using this formulas to calculate visible width & height

var vFOV = camera.fov * Math.PI / 180;        // convert vertical fov to radians
var height = 2 * Math.tan( vFOV / 2 ) * dist; // visible height

var aspect = window.width / window.height;
var width = height * aspect;                  // visible width

And with that I calculate the camera zoom required for object to fit exactly into render area by WIDTH

var zoom = (ObjectHeight/aspect) / (2*Math.tan(vFOV/2)) + ObjectDepth;

How do I calculate the camera zoom required for object to fit exactly into render area by HEIGHT?

Thanks to GuyGood, I found the solution:

var zoom = (ObjectHeight/2) / Math.tan(vFOV/2) - ObjectDepth;

解决方案

I am doing the following which is based on the boundingSphere radius:

geometry.computeBoundingSphere();
radius = geometry.boundingSphere.radius;
distanceFactor = Math.abs( aspect * radius / Math.sin( fov/2 );

This is based on this stuff right here and I hope i interpreted it the right way: http://www.flipcode.com/forums/thread/4172

This distanceFactor is the factor you need to move the camera along its viewing direction to fit it correctly. At the moment i am not sure if it is by height or width but maybe it helps you figure it out. :)

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