Question

我正在使用Three.js创建一个场景，我可以移动对象。我使用OBJMTLLoader加载对象。然而，这些物品不具有本地来源，它们仍然存储它们的原始来源。当我去移动一个物体时，物体首先移回原来的原点，然后你可以从那里移动物体。我已经找到了许多使用质心和边界框的例子，但我总是得到一些未定义的东西。任何帮助将不胜感激!!

loader.load('example.obj', 'example.mtl', function (object) {
            object.position.y = -50; // I want this to be the new origin of the object
            object.scale.set(scale, scale, scale);
        });

然后我移动对象的代码：

function onDocumentMouseMove(event) {
    event.preventDefault();
    mouse.x = ( (event.clientX - container.offsetLeft) / container.clientWidth ) * 2 - 1;
    mouse.y = -( (event.clientY - container.offsetTop ) / container.clientHeight) * 2 + 1;

    raycaster.setFromCamera(mouse, camera);

    if (SELECTED) {
        var intersects = raycaster.intersectObject(plane);
        SELECTED.position.copy(intersects[0].point.sub(offset));
        return;
    }

    var intersects = raycaster.intersectObjects(objects);
    if (intersects.length > 0) {
        if (INTERSECTED != intersects[0].object) {
            INTERSECTED = intersects[0].object;
            plane.position.copy(INTERSECTED.position);
            plane.lookAt(camera.position);
            updateLightPosition();
        }
        container.style.cursor = 'pointer';
    } else {
        INTERSECTED = null;
        container.style.cursor = 'auto';
    }
}

function onDocumentMouseDown(event) {
    event.preventDefault();
    var vector = new THREE.Vector3(mouse.x, mouse.y, 1).unproject(camera);
    raycaster.set(camera.position, vector.sub(camera.position).normalize());
    if (selectingTargetPos) {
        var intersects = raycaster.intersectObjects(background);
        if (intersects.length > 0) {
            selectedObject.light.target = new THREE.Object3D();
            selectedObject.light.target.position.copy(intersects[0].point);
            selectedObject.light.target.updateMatrixWorld();
            selectingTargetPos = false;
            container.style.cursor = 'auto';
        }
    } else if (selectingTargetObj) {
        var intersects = raycaster.intersectObjects(objects);
        if (intersects.length > 0) {
            selectedObject.light.target = intersects[0].object;
            selectedObject.light.target.updateMatrixWorld();
            selectingTargetObj = false;
            container.style.cursor = 'auto';
        }
    } else {
        var intersects = raycaster.intersectObjects(objects, true);
        if (intersects.length > 0) {
            SELECTED = intersects[0].object.userData.rootObject;
            selectedObject = SELECTED;
            var intersects = raycaster.intersectObject(plane);
            offset.copy(intersects[0].point).sub(plane.position);
            container.style.cursor = 'move';
        }
    }
}

function onDocumentMouseUp(event) {
    event.preventDefault();
    SELECTED = null;
    container.style.cursor = 'auto';
}

Answer 1

由于对象位置基于平面并且对象已分组，因此问题出在INTERSECTED事件的onDocumentMouseMove()块中。

这不会被触发，因为raycaster没有递归地检查对象数组。通过将intersectObjects()函数更改为第二个参数为true，问题将得到解决。

var intersects = raycaster.intersectObjects(objects, true);
if (intersects.length > 0) {
    if (INTERSECTED != intersects[0].object) {
        INTERSECTED = intersects[0].object;
        plane.position.copy(INTERSECTED.position);
        plane.lookAt(camera.position);
        updateLightPosition();
    }
    container.style.cursor = 'pointer';
} else {
    INTERSECTED = null;
    container.style.cursor = 'auto';
}

无法在场景中为OBJMTLLoader对象设置本地原点

1 个答案: