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I imported a model and found that shadow only show in a small area(green area in the picture). What can I do to let all objects show their shadow.

Here is my code.

light = new THREE.DirectionalLight( 0xffffff );
light.position.set( 1, 1, 1 );
light.castShadow = true;
light.shadow.camera.near = 0.01; // same as the camera
light.shadow.camera.far = 1000; // same as the camera
light.shadow.camera.fov = 50; // same as the camera
light.shadow.mapSize.width = 2048;
light.shadow.mapSize.height = 2048;
scene.add( light );

Thanks!!

EDIT:

I add gui to change light.shadow.camera.top / light.shadow.camera.bottom / light.shadow.camera.left / light.shadow.camera.right, but nothing happens.

var gui = new dat.GUI();
gui.add( light.shadow.camera, 'top' ).min( 1 ).max( 100000 ).onChange( function ( value ) {
    light.shadow.camera.bottom = -value;
    light.shadow.camera.left = value;
    light.shadow.camera.right = -value;
});

I imported a model and found that shadow only show in a small area(green area in the picture). What can I do to let all objects show their shadow.

Here is my code.

light = new THREE.DirectionalLight( 0xffffff );
light.position.set( 1, 1, 1 );
light.castShadow = true;
light.shadow.camera.near = 0.01; // same as the camera
light.shadow.camera.far = 1000; // same as the camera
light.shadow.camera.fov = 50; // same as the camera
light.shadow.mapSize.width = 2048;
light.shadow.mapSize.height = 2048;
scene.add( light );

Thanks!!

EDIT:

I add gui to change light.shadow.camera.top / light.shadow.camera.bottom / light.shadow.camera.left / light.shadow.camera.right, but nothing happens.

var gui = new dat.GUI();
gui.add( light.shadow.camera, 'top' ).min( 1 ).max( 100000 ).onChange( function ( value ) {
    light.shadow.camera.bottom = -value;
    light.shadow.camera.left = value;
    light.shadow.camera.right = -value;
});

• javascript
• three.js
• model

Share Improve this question Follow edited Jun 15, 2019 at 13:28 user128511 asked May 7, 2019 at 4:32 TiffanyTiffany 23911 gold badge88 silver badges1717 bronze badges

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3 Answers 3

Sorted by: Reset to default 4

That's happening because directional lights use an OrthographicCamera to draw a shadowmap to cast shadows. If there are objects outside the view of this camera, it won't be able to calculate their shadows, and will have the effect you're seeing outside the green box. If you want to extend the area that this camera covers, you can modify the .left .right .top .bottom properties of this shadow camera to cover your entire scene. I'm using a box of 100 units in the example below;

var side = 100;
light.shadow.camera.top = side;
light.shadow.camera.bottom = -side;
light.shadow.camera.left = side;
light.shadow.camera.right = -side;

... but you can change the dimensions to whatever you need. Keep in mind that .fov does nothing in your example code because ortho cameras don't use the field-of-view property.

All right, it would be great if you could show me a live example of your code as I have fixed this before for a project in boxelizer.

The issue can be fixed by changing the light.shadow.camera.left, right, bottom and top properties as suggested before, however we might not be able to see what the effective area of our shadow might be and hence we might be really close to fixing it but not at all. My suggestion is using a helper momentarily just to see the effective shadow area of your light with:

var shadowHelper = new THREE.CameraHelper( light.shadow.camera );
scene.add( shadowHelper );

You are also wele to see all the code I used in the link I referenced to.

Here's a function I use to set the shadowMap dimensions and coverage area:

//sz is the size in world units that the shadow should cover. (area)
// mapSize is the width,height of the texture to be used for shadowmap (resolution)
    var setShadowSize=(light1, sz, mapSz)=>{
        light1.shadow.camera.left = sz;
        light1.shadow.camera.bottom = sz;
        light1.shadow.camera.right = -sz;
        light1.shadow.camera.top = -sz;
        if(mapSz){
            light1.shadow.mapSize.set(mapSz,mapSz)
        }
    }
    setShadowSize(myLight,15.0,1024);

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