three.js calculate STL file mesh volume

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-1

I have to calculate the volume of an STL file, I successfully got the sizes of the model with

var box = new THREE.Box3().setFromObject( mesh );

var sizes = box.getSize();

but I just can't wrap my head around the concept of calculating it. I load the model with

var loader = new THREE.STLLoader();

loader.load(stlFileURL, function ( geometry ) {});

Can someone help me out and point me in the right direction? I'm doing it with javascript.

asked Nov 24 '18 at 14:37

John

269

Are you trying to estimate how much filament for 3d printing?

– manthrax
Nov 24 '18 at 17:03

Have a look at this SO thread.

– prisoner849
Nov 24 '18 at 17:58

@manthrax exactly

– John
Nov 24 '18 at 20:22

add a comment |

-1

I have to calculate the volume of an STL file, I successfully got the sizes of the model with

var box = new THREE.Box3().setFromObject( mesh );

var sizes = box.getSize();

but I just can't wrap my head around the concept of calculating it. I load the model with

var loader = new THREE.STLLoader();

loader.load(stlFileURL, function ( geometry ) {});

Can someone help me out and point me in the right direction? I'm doing it with javascript.

asked Nov 24 '18 at 14:37

John

269

Are you trying to estimate how much filament for 3d printing?

– manthrax
Nov 24 '18 at 17:03

Have a look at this SO thread.

– prisoner849
Nov 24 '18 at 17:58

@manthrax exactly

– John
Nov 24 '18 at 20:22

add a comment |

-1

I have to calculate the volume of an STL file, I successfully got the sizes of the model with

var box = new THREE.Box3().setFromObject( mesh );

var sizes = box.getSize();

but I just can't wrap my head around the concept of calculating it. I load the model with

var loader = new THREE.STLLoader();

loader.load(stlFileURL, function ( geometry ) {});

Can someone help me out and point me in the right direction? I'm doing it with javascript.

asked Nov 24 '18 at 14:37

John

269

I have to calculate the volume of an STL file, I successfully got the sizes of the model with

var box = new THREE.Box3().setFromObject( mesh );

var sizes = box.getSize();

but I just can't wrap my head around the concept of calculating it. I load the model with

var loader = new THREE.STLLoader();

loader.load(stlFileURL, function ( geometry ) {});

Can someone help me out and point me in the right direction? I'm doing it with javascript.

javascript three.js

asked Nov 24 '18 at 14:37

John

269

asked Nov 24 '18 at 14:37

John

269

asked Nov 24 '18 at 14:37

John

269

asked Nov 24 '18 at 14:37

John

269

asked Nov 24 '18 at 14:37

John

269

Are you trying to estimate how much filament for 3d printing?

– manthrax
Nov 24 '18 at 17:03

Have a look at this SO thread.

– prisoner849
Nov 24 '18 at 17:58

@manthrax exactly

– John
Nov 24 '18 at 20:22

add a comment |

Are you trying to estimate how much filament for 3d printing?

– manthrax
Nov 24 '18 at 17:03

Have a look at this SO thread.

– prisoner849
Nov 24 '18 at 17:58

@manthrax exactly

– John
Nov 24 '18 at 20:22

Are you trying to estimate how much filament for 3d printing?

– manthrax
Nov 24 '18 at 17:03

Have a look at this SO thread.

– prisoner849
Nov 24 '18 at 17:58

@manthrax exactly

– John
Nov 24 '18 at 20:22

add a comment |

2 Answers
2

active

oldest

votes

You can find it with the algorithm from my comment.

In the code snippet, the volume is computed without scaling.

Also, I've added a simple check that the algorithm calculates correctly by finding the volume of a hollow cylinder. As THREE.STLLoader() returns a non-indexed geometry, I've casted the geometry of the cylinder to non-indexed too.

Related forum topic

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

1

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

1

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

|
show 3 more comments

-1

This is a pretty tricky problem. One way is to decompose the object into a bunch of convex polyhedra and sum the volumes of those...

Another way is to voxelize it, and add up the voxels on the inside to get an estimate whos accuracy is limited by the resolution of your voxelization.

Edit: prisoner849 has a rad solution!

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

add a comment |

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2 Answers
2

active

oldest

votes

2 Answers
2

active

oldest

votes

You can find it with the algorithm from my comment.

In the code snippet, the volume is computed without scaling.

Related forum topic

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

1

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

1

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

|
show 3 more comments

You can find it with the algorithm from my comment.

In the code snippet, the volume is computed without scaling.

Related forum topic

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

1

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

1

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

|
show 3 more comments

You can find it with the algorithm from my comment.

In the code snippet, the volume is computed without scaling.

Related forum topic

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

You can find it with the algorithm from my comment.

In the code snippet, the volume is computed without scaling.

Related forum topic

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

var scene = new THREE.Scene();

var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1000);

camera.position.setScalar(20);

var renderer = new THREE.WebGLRenderer();

renderer.setClearColor(0x404040);

renderer.setSize(window.innerWidth, window.innerHeight);

document.body.appendChild(renderer.domElement);



var controls = new THREE.OrbitControls(camera, renderer.domElement);



var loader = new THREE.STLLoader();

loader.load('https://threejs.org/examples/models/stl/binary/pr2_head_pan.stl', function(geometry) {



  var mesh = new THREE.Mesh(geometry, new THREE.MeshBasicMaterial({

    color: 0xff00ff,

    wireframe: true

  }));

  mesh.rotation.set(-Math.PI / 2, 0, 0);

  mesh.scale.setScalar(100);

  scene.add(mesh);



  console.log("stl volume is " + getVolume(geometry));

});



// check with known volume:

var hollowCylinderGeom = new THREE.LatheBufferGeometry([

  new THREE.Vector2(1, 0),

  new THREE.Vector2(2, 0),

  new THREE.Vector2(2, 2),

  new THREE.Vector2(1, 2),

  new THREE.Vector2(1, 0)

], 90).toNonIndexed();

console.log("pre-computed volume of a hollow cylinder (PI * (R^2 - r^2) * h): " + Math.PI * (Math.pow(2, 2) - Math.pow(1, 2)) * 2);

console.log("computed volume of a hollow cylinder: " + getVolume(hollowCylinderGeom));





function getVolume(geometry) {



  let position = geometry.attributes.position;

  let faces = position.count / 3;

  let sum = 0;

  let p1 = new THREE.Vector3(),

    p2 = new THREE.Vector3(),

    p3 = new THREE.Vector3();

  for (let i = 0; i < faces; i++) {

    p1.fromBufferAttribute(position, i * 3 + 0);

    p2.fromBufferAttribute(position, i * 3 + 1);

    p3.fromBufferAttribute(position, i * 3 + 2);

    sum += signedVolumeOfTriangle(p1, p2, p3);

  }

  return sum;



}



function signedVolumeOfTriangle(p1, p2, p3) {

  return p1.dot(p2.cross(p3)) / 6.0;

}



renderer.setAnimationLoop(() => {

  renderer.render(scene, camera);

});

body {

  overflow: hidden;

  margin: 0;

}

<script src="https://threejs.org/build/three.min.js"></script>

<script src="https://threejs.org/examples/js/loaders/STLLoader.js"></script>

<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

edited Nov 27 '18 at 9:12

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

answered Nov 25 '18 at 22:02

prisoner849

7,87821430

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

1

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

1

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

|
show 3 more comments

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

1

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

1

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

This calculates the sum of the areas of the triangles?

– manthrax
Nov 26 '18 at 13:51

Whoa. Never mind. This is pretty slick. but only works for convex objects, yeah?

– manthrax
Nov 26 '18 at 13:52

@manthrax Works for those geometries that have no self-intersections/overlapping.

– prisoner849
Nov 26 '18 at 13:56

so for 3d printing filament estimation, it would overestimate on objects with those features. Might be an acceptable tradeoff. But imagine printing a flowerpot.. the overestimation would be huuuge.

– manthrax
Nov 26 '18 at 14:06

@manthrax Yes, it's not mandatory for the model's geometry to be positioned in the center of coordinates, the algorithm will calculate its volume.

– prisoner849
Nov 27 '18 at 9:07

|
show 3 more comments

-1

This is a pretty tricky problem. One way is to decompose the object into a bunch of convex polyhedra and sum the volumes of those...

Another way is to voxelize it, and add up the voxels on the inside to get an estimate whos accuracy is limited by the resolution of your voxelization.

Edit: prisoner849 has a rad solution!

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

add a comment |

-1

This is a pretty tricky problem. One way is to decompose the object into a bunch of convex polyhedra and sum the volumes of those...

Another way is to voxelize it, and add up the voxels on the inside to get an estimate whos accuracy is limited by the resolution of your voxelization.

Edit: prisoner849 has a rad solution!

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

add a comment |

-1

This is a pretty tricky problem. One way is to decompose the object into a bunch of convex polyhedra and sum the volumes of those...

Another way is to voxelize it, and add up the voxels on the inside to get an estimate whos accuracy is limited by the resolution of your voxelization.

Edit: prisoner849 has a rad solution!

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

This is a pretty tricky problem. One way is to decompose the object into a bunch of convex polyhedra and sum the volumes of those...

Another way is to voxelize it, and add up the voxels on the inside to get an estimate whos accuracy is limited by the resolution of your voxelization.

Edit: prisoner849 has a rad solution!

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

edited Nov 27 '18 at 6:59

answered Nov 24 '18 at 17:01

manthrax

2,52211010

answered Nov 24 '18 at 17:01

manthrax

2,52211010

answered Nov 24 '18 at 17:01

manthrax

2,52211010

add a comment |

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