ray无法访问JSON

Question

我正在尝试使用鼠标单击事件来捕获JSON对象。我使用光线来识别对象，但由于某些原因，对象并不总是被识别。我怀疑这与我移动相机的事实有关，因为当我在物体附近单击时，我就被识别了。

你能帮我弄清楚如何根据相机的移动来正确设置光线吗？

代码如下：

这是鼠标按下事件的一部分*

    document.addEventListener("mousemove", onDocumentMouseMove, false);
    document.addEventListener("mouseup", onDocumentMouseUp, false);
    document.addEventListener("mouseout", onDocumentMouseOut, false);
    mouseXOnMouseDown = event.clientX - windowHalfX;
    targetRotationOnMouseDown = targetRotation;
    var ray, intersections;
    _vector.set((event.clientX / window.innerWidth) * 2 - 1, -(event.clientY / window.innerHeight) * 2 + 1, 0);
    projector.unprojectVector(_vector, camera);
    ray = new THREE.Ray(camera.position, _vector.subSelf(camera.position).normalize());
    intersections = ray.intersectObjects(furniture);

    if (intersections.length > 0) {
        selected_block = intersections[0].object;
        _vector.set(0, 0, 0);
        selected_block.setAngularFactor(_vector);
        selected_block.setAngularVelocity(_vector);
        selected_block.setLinearFactor(_vector);
        selected_block.setLinearVelocity(_vector);
        mouse_position.copy(intersections[0].point);
        block_offset.sub(selected_block.position, mouse_position);
        intersect_plane.position.y = mouse_position.y;
    }

}

这是相机移动的一部分*

camera.position.x = (Math.cos(timer) * 10);
camera.position.z = (Math.sin(timer) * 10);
camera.lookAt(scene.position); 

Answer 1

嗯，如果看不到你的程序实际是如何运行的，就很难说出你的问题是什么。我建议看看我今天一直在做的演示。我处理我的相机，控制器和光线。我也在使用JSON。

首先，您可以查看我的演示：，以了解它在做什么，以及您的描述听起来很相似。你应该能够改编我的代码，如果你能理解它。

--如果您想要直接链接到源代码：

我也有另一个你可能会发现有用的地方，我使用光线和鼠标碰撞到。

--源代码：

最后，我将在第一个演示中发布我的鼠标事件的内部以及我如何使用跟踪球摄像头来处理它，希望其中的一些内容将引导您找到解决方案：

/** Event fired when the mouse button is pressed down */
function onDocumentMouseDown(event) {
    event.preventDefault();

    /** Calculate mouse position and project vector through camera and mouse3D */
    mouse3D.x = mouse2D.x = (event.clientX / window.innerWidth) * 2 - 1;
    mouse3D.y = mouse2D.y = -(event.clientY / window.innerHeight) * 2 + 1;
    mouse3D.z = 0.5;
    projector.unprojectVector(mouse3D, camera);

    var ray = new THREE.Ray(camera.position, mouse3D.subSelf(camera.position).normalize());

    var intersects = ray.intersectObject(maskMesh);

    if (intersects.length > 0) {
        SELECTED = intersects[0].object;
        var intersects = ray.intersectObject(plane);
        offset.copy(intersects[0].point).subSelf(plane.position);
        killControls = true;
    }
    else if (controls.enabled == false)
        controls.enabled = true;
}

/** This event handler is only fired after the mouse down event and
    before the mouse up event and only when the mouse moves */
function onDocumentMouseMove(event) {
    event.preventDefault();

    /** Calculate mouse position and project through camera and mouse3D */
    mouse3D.x = mouse2D.x = (event.clientX / window.innerWidth) * 2 - 1;
    mouse3D.y = mouse2D.y = -(event.clientY / window.innerHeight) * 2 + 1;
    mouse3D.z = 0.5;
    projector.unprojectVector(mouse3D, camera);

    var ray = new THREE.Ray(camera.position, mouse3D.subSelf(camera.position).normalize());

    if (SELECTED) {
        var intersects = ray.intersectObject(plane);
        SELECTED.position.copy(intersects[0].point.subSelf(offset));
        killControls = true;
        return;
    }

    var intersects = ray.intersectObject(maskMesh);

    if (intersects.length > 0) {
        if (INTERSECTED != intersects[0].object) {
            INTERSECTED = intersects[0].object;
            INTERSECTED.currentHex = INTERSECTED.material.color.getHex();
            plane.position.copy(INTERSECTED.position);
        }
    }
    else {
        INTERSECTED = null;
    }
}

/** Removes event listeners when the mouse button is let go */
function onDocumentMouseUp(event) {
    event.preventDefault();
    if (INTERSECTED) {
        plane.position.copy(INTERSECTED.position);
        SELECTED = null;
        killControls = false;
    }

}

/** Removes event listeners if the mouse runs off the renderer */
function onDocumentMouseOut(event) {
    event.preventDefault();
    if (INTERSECTED) {
        plane.position.copy(INTERSECTED.position);
        SELECTED = null;
    }
}

为了在我的第一个演示中获得我想要的效果，我必须将这个添加到我的动画循环中，以便使用killControls标志来基于鼠标碰撞有选择地打开和关闭轨迹球相机控件：

if (!killControls) controls.update(delta);
else controls.enabled = false;